Luminous Landscape Forum

Raw & Post Processing, Printing => Digital Image Processing => Topic started by: Eric Brody on February 12, 2010, 11:50:33 AM

Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Eric Brody on February 12, 2010, 11:50:33 AM
PhotoKit sharpener has been recommended to me by a friend from whom I took a course and whose work I respect. As I read through all the material and search various fora, I get more and more confused about input sharpening. Martin Evening's Lightroom 2 book and Schewe and Fraser's latest book on sharpening discuss the apparently excellent algorithms in Lightroom's input sharpening and how they are similar to the input sharpening in Photokit Sharpener. I have emailed him for his own ideas, since he's quite knowledgeable but thought I might get some other ideas here.

What should the workflow be? I import my files into Lightroom, adjust them there, and then go on to Photoshop for more detailed work, then print with Photoshop (CS3), using output sharpening at the final print size. Should I ignore, set to zero, the Lightroom sharpening, and do everything in Photoshop with Photokit, or should I use the Lightroom sharpening and if so, how does that affect input-content sharpening down the road in Photoshop with PhotoKit and, is it redundant or worst, will I oversharpen?

Thanks so much.

Eric
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: PeterAit on February 12, 2010, 11:59:30 AM
Quote from: brodyer
PhotoKit sharpener has been recommended to me by a friend from whom I took a course and whose work I respect. As I read through all the material and search various fora, I get more and more confused about input sharpening. Martin Evening's Lightroom 2 book and Schewe and Fraser's latest book on sharpening discuss the apparently excellent algorithms in Lightroom's input sharpening and how they are similar to the input sharpening in Photokit Sharpener. I have emailed him for his own ideas, since he's quite knowledgeable but thought I might get some other ideas here.

What should the workflow be? I import my files into Lightroom, adjust them there, and then go on to Photoshop for more detailed work, then print with Photoshop (CS3), using output sharpening at the final print size. Should I ignore, set to zero, the Lightroom sharpening, and do everything in Photoshop with Photokit, or should I use the Lightroom sharpening and if so, how does that affect input-content sharpening down the road in Photoshop with PhotoKit and, is it redundant or worst, will I oversharpen?

Thanks so much.

Eric

PK Sharpener is indeed a great tool. Using PKS in Photoshop gives you more flexibility than input sharpening in LR because you can select the degree of sharpening based on the amount of detail in the photo. LR input sharpening is supposed to be excellent but it is "one size fits all" pretty much. My workflow is very similar to yours, and I always set sharpening to 0 in LR and do it in PS. I do lots of other adjustments in LR, but not sharpening.

Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: ErikKaffehr on February 12, 2010, 12:02:14 PM
Hi,

The sharpening in Lightroom is essentially based on PhotoKit Sharpener. The algorithm is probably a bit better in LR as it's coded directly instead of using the methods available in PS. For instance the detail slider adjusts halo intensity, a control that is not available in PS.

What missing from LR is creative sharpnening. My suggestion would be to use LR for capture sharpening, use PS and PKS for creative sharpening (if needed) and use LR for output sharpening and printing.

Best regards
Erik


Quote from: brodyer
PhotoKit sharpener has been recommended to me by a friend from whom I took a course and whose work I respect. As I read through all the material and search various fora, I get more and more confused about input sharpening. Martin Evening's Lightroom 2 book and Schewe and Fraser's latest book on sharpening discuss the apparently excellent algorithms in Lightroom's input sharpening and how they are similar to the input sharpening in Photokit Sharpener. I have emailed him for his own ideas, since he's quite knowledgeable but thought I might get some other ideas here.

What should the workflow be? I import my files into Lightroom, adjust them there, and then go on to Photoshop for more detailed work, then print with Photoshop (CS3), using output sharpening at the final print size. Should I ignore, set to zero, the Lightroom sharpening, and do everything in Photoshop with Photokit, or should I use the Lightroom sharpening and if so, how does that affect input-content sharpening down the road in Photoshop with PhotoKit and, is it redundant or worst, will I oversharpen?

Thanks so much.

Eric
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: francois on February 12, 2010, 12:02:55 PM
Eric,
Here's my workflow:
• Import and tag photos in Lightroom.
• Adjust and capture sharpen in Lightroom.
• If I need to go in Photoshop, I use Edit in Photoshop command from Lightroom (Optional).
• Perform creative sharpening (using PKS) and other stuff in Photoshop (Optional),
• Save the image in Photoshop (Optional).
• Print from Lightroom.

I must say that, these days,  my photos are rarely edited in Photoshop.
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: ErikKaffehr on February 12, 2010, 12:07:26 PM
Hi,

Yes I also use PS less and less. The problem with PS is essentially that the parametric workflow is broken. So if I want to make a small change to capture processing I need to redo everything in PS.

Best regards
Erik

Quote from: francois
Eric,
Here's my workflow:
Import and tag photos in Lightroom.
Adjust and capture sharpen in Lightroom.
If I need to go in Photoshop, I use Edit in Photoshop command from Lightroom (Optional).
Perform creative sharpening (using PKS) and other stuff in Photoshop (Optional),
Save the image in Photoshop (Optional).
Print from Lightroom.

I must say that, these days,  my photos are rarely edited in Photoshop.
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: francois on February 12, 2010, 12:12:48 PM
Quote from: ErikKaffehr
Hi,

Yes I also use PS less and less. The problem with PS is essentially that the parametric workflow is broken. So if I want to make a small change to capture processing I need to redo everything in PS.

Best regards
Erik
Erik,
That's exactly why I avoid the Photoshop route if possible. A possible workaround would be to use smart objects but I haven't investigated much.
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Mark D Segal on February 12, 2010, 12:17:16 PM
Quote from: brodyer
PhotoKit sharpener has been recommended to me by a friend from whom I took a course and whose work I respect. As I read through all the material and search various fora, I get more and more confused about input sharpening. Martin Evening's Lightroom 2 book and Schewe and Fraser's latest book on sharpening discuss the apparently excellent algorithms in Lightroom's input sharpening and how they are similar to the input sharpening in Photokit Sharpener. I have emailed him for his own ideas, since he's quite knowledgeable but thought I might get some other ideas here.

What should the workflow be? I import my files into Lightroom, adjust them there, and then go on to Photoshop for more detailed work, then print with Photoshop (CS3), using output sharpening at the final print size. Should I ignore, set to zero, the Lightroom sharpening, and do everything in Photoshop with Photokit, or should I use the Lightroom sharpening and if so, how does that affect input-content sharpening down the road in Photoshop with PhotoKit and, is it redundant or worst, will I oversharpen?

Thanks so much.

Eric

If you do the capture sharpening in LR using the LR sharpener in the Develop module, you are sharpening the file before rendering and that may be technically advantageous. You do have considerable control over the strength and applicability (with the mask feature) of the sharpening in LR, and it performs very, very well (from my experience with it over at least a thousand prints), so I would recommend doing the capture sharpening in LR. If you need "creative sharpening", you would do that in PS where it is available, and if you are printing from CS3, do the Output Sharpening from PS too. Just avoid repeating the Capture Sharpening in PS if you have already sharpened in the Develop Module of LR as recommended here.
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: JeffKohn on February 12, 2010, 12:57:21 PM
I personally never liked the PKS capture sharpener (although the output sharpener is pretty good). My problem with it is the use of an edge mask. This makes no sense to me for capture sharpening (unless you're shooting noisy high-ISO), because the AA filter and bayer interpolation don't just affect edges; they also affect fine details which can benefit from capture sharpening. At least with LR/ACR capture sharpening you can disable the edge mask.

For capture sharpening, I prefer deconvulation-based sharpening. I use Focus Magic. But I take all images into Photoshop, so trying to stay with an all-parametric workflow isn't an issue for me. (I don't like the LR paradigm, prefer to stick with Bridge/Photoshop).
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Mark D Segal on February 12, 2010, 01:55:02 PM
Quote from: JeffKohn
I personally never liked the PKS capture sharpener (although the output sharpener is pretty good). My problem with it is the use of an edge mask. This makes no sense to me for capture sharpening (unless you're shooting noisy high-ISO), because the AA filter and bayer interpolation don't just affect edges; they also affect fine details which can benefit from capture sharpening. At least with LR/ACR capture sharpening you can disable the edge mask.

For capture sharpening, I prefer deconvulation-based sharpening. I use Focus Magic. But I take all images into Photoshop, so trying to stay with an all-parametric workflow isn't an issue for me. (I don't like the LR paradigm, prefer to stick with Bridge/Photoshop).

That's why PK Capture Sharpener Pro has four settings depending on the frequency of the image detail. For high frequency images you can use Super Fine Edge Sharpen and it does a great job. Much more satisfactory to my taste than Focus Magic, which I find pretty rough - that program is very good for unearthing information which is blurred, but otherwise I wouldn't use it as a general sharpener meant to counteract anti-aliasing or more generally the softening effect of digitzation processes. But, "chacun a son gout".
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: ErikKaffehr on February 12, 2010, 03:17:12 PM
Hi,

Regarding parametric workflow vs. Bridge/Photoshop it is really simple. If the parametric workflow is not advantageous than there is no need to use it. If all images are edited in Photoshop the parametric workflow will be broken and there is little reason to use Lightroom. ACR has the same controls, by and large, as Lightroom. In addition, any RAW converter can be used in a non parametric workflow.

For me the parametric part of the workflow is important, so I use Lightroom.

Regarding different sharpening techniques I used to use Focus Magic, but they never made it work with Intel based Macs, so I did a lot of testing on different tools and it is not obvious to me that any sharpening tool would be vastly superior to others.

The reason that edge masking is preferable is that agressive sharpening will also increase noise. The is little reason to sharpen surfaces with little detail, like the sky.

The main advantage with using LR for printing is that it takes care of both upscaling and sharpening for output.

Best regards
Erik

Quote from: JeffKohn
I personally never liked the PKS capture sharpener (although the output sharpener is pretty good). My problem with it is the use of an edge mask. This makes no sense to me for capture sharpening (unless you're shooting noisy high-ISO), because the AA filter and bayer interpolation don't just affect edges; they also affect fine details which can benefit from capture sharpening. At least with LR/ACR capture sharpening you can disable the edge mask.

For capture sharpening, I prefer deconvulation-based sharpening. I use Focus Magic. But I take all images into Photoshop, so trying to stay with an all-parametric workflow isn't an issue for me. (I don't like the LR paradigm, prefer to stick with Bridge/Photoshop).
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: JeffKohn on February 12, 2010, 03:25:59 PM
Quote from: Mark D Segal
That's why PK Capture Sharpener Pro has four settings depending on the frequency of the image detail. For high frequency images you can use Super Fine Edge Sharpen and it does a great job.
Those settings vary the edge mask, but I don't think even the  "super fine" option completely eliminates it.

Quote
Much more satisfactory to my taste than Focus Magic, which I find pretty rough - that program is very good for unearthing information which is blurred, but otherwise I wouldn't use it as a general sharpener meant to counteract anti-aliasing or more generally the softening effect of digitzation processes. But, "chacun a son gout".
I don't think Focus Magic is rough at all if you use the correct settings.  The nice thing about it, is much less prone to creating halos than any normal USM or HPF approach. I don't want halos in my capture sharpening.
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: JeffKohn on February 12, 2010, 03:34:00 PM
Quote from: ErikKaffehr
Hi,

Regarding parametric workflow vs. Bridge/Photoshop it is really simple. If the parametric workflow is not advantageous than there is no need to use it. If all images are edited in Photoshop the parametric workflow will be broken and there is little reason to use Lightroom. ACR has the same controls, by and large, as Lightroom. In addition, any RAW converter can be used in a non parametric workflow.
Agreed. LR just doesn't suit me, but I understand why people like it. (Some people tend to get a little religious about it, though; almost like the Mac cult-members.  )

Quote
The reason that edge masking is preferable is that agressive sharpening will also increase noise. The is little reason to sharpen surfaces with little detail, like the sky.
For me this just isn't an issue at base ISO, but I guess it depends what you mean by "aggressive" sharpening as I tend to be pretty conservative with capture sharpening. It may be that I just prefer less sharpening than many people, I can't remember the last time I used "creative" sharpening.  With the D300 I occasionally needed to mask out the sky when sharpening, but with the other Nikon's I've used it just isn't an issue at base ISO. And even when some masking is beneficial, I prefer to do it myself rather than with an automated script.
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: ErikKaffehr on February 12, 2010, 03:38:01 PM
Hi,

In LR we can select the amount of edge masking.

The detail slider is to my understanding really "halo supression". At zero there will be no halos and the halos increase when the slider is moved to higher values. My preferred sharpening is relatively high amount, low radius and some "detail".

Best regards
Erik



Quote from: JeffKohn
Those settings vary the edge mask, but I don't think even the  "super fine" option completely eliminates it.


I don't think Focus Magic is rough at all if you use the correct settings.  The nice thing about it, is much less prone to creating halos than any normal USM or HPF approach. I don't want halos in my capture sharpening.
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Mark D Segal on February 12, 2010, 04:00:24 PM
Quote from: JeffKohn
Those settings vary the edge mask, but I don't think even the  "super fine" option completely eliminates it.


I don't think Focus Magic is rough at all if you use the correct settings.  The nice thing about it, is much less prone to creating halos than any normal USM or HPF approach. I don't want halos in my capture sharpening.

I use LR sharpening and there are no visible halos in my capture sharpening - zip - nada.

I've experimented with various Focus Magic settings and never got it to work to my satisfaction, except for rescuing blurred image detail. But, as I said, each to his/her own.
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Mark D Segal on February 12, 2010, 04:04:59 PM
Quote from: JeffKohn
Agreed. LR just doesn't suit me, but I understand why people like it. (Some people tend to get a little religious about it, though; almost like the Mac cult-members.  )


For me this just isn't an issue at base ISO, but I guess it depends what you mean by "aggressive" sharpening as I tend to be pretty conservative with capture sharpening. It may be that I just prefer less sharpening than many people, I can't remember the last time I used "creative" sharpening.  With the D300 I occasionally needed to mask out the sky when sharpening, but with the other Nikon's I've used it just isn't an issue at base ISO. And even when some masking is beneficial, I prefer to do it myself rather than with an automated script.

I too tend to be somewhat conservative with all sharpening. The last thing I want is crunchy-looking images. But when you use LR's capture sharpening, you're not strictly speaking selling your soul to an automated script. You can vary the masking to suit the image, and the other controls above it too. On the whole, for dealing with stuff like skies and skin tones where over-sharpening can be the biggest headache, I find it's pretty darn good.
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: JeffKohn on February 12, 2010, 05:56:26 PM
Sorry if I wasn't clear, my criticisms are more with PKS than with LR's sharpening. I agree you've got more control over the sharpening parameters (including masking) in LR/ACR.

I would expect if a new version of PKS is coming out, the capture sharpening will offer even more control, since otherwise I'm not sure what it would bring to the table over LR/ACR except for the option of having a layer in PS that you can work with.
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: BartvanderWolf on February 12, 2010, 06:31:23 PM
Quote from: Mark D Segal
I've experimented with various Focus Magic settings and never got it to work to my satisfaction, except for rescuing blurred image detail. But, as I said, each to his/her own.

There should not be "various" FocusMagic settings. There usually is one optimal radius setting, and an amount of 100% is usually the best choice, although with a large radius one might want to increase the percentage to taste.

Cheers,
Bart
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Schewe on February 12, 2010, 06:42:24 PM
Quote from: JeffKohn
I would expect if a new version of PKS is coming out, the capture sharpening will offer even more control, since otherwise I'm not sure what it would bring to the table over LR/ACR except for the option of having a layer in PS that you can work with.

Well, if one knows the tools, Lightroom and/or Camera Raw are optimal for capture sharpening because you can incorporate both the sharpening AND the noise reduction at the same time. Those who have used the Lightroom 3 beta have had a taste of the new demosiacing/sharpening/noise reduction capabilities...note that luminance noise reduction wasn't included in the beta but one would expect that when it's added it will be as much of a breakthrough as the improved demosiacing and color noise reduction (some of us have knowledge that we can't discuss due to NDA's)

As far as I'm concerned, I doubt that PhotoKit Sharpener 2.0 will be able to do much if anything better than ACR 6/LR 3 for digital capture...I certainly won't be using it for capture sharpening even though it's "our" product...

I do think that currently (LR 2.6) the optimal lace for output sharpening is in Lightroom's Print module which IS directly formulated from PhotoKit Sharpener's output sharpening...that's what I use for output since I can create one master ProPhoto RGB file, retouched, soft proof prepped and all set to print to any size I need...

The big question going forward is "creative sharpening" or sharpening for effect. Clearly the local sharpening controls are limited (although expect to see improvements in LR 3). When you need to aggressively go in and create effect sharpening, there's really no alternative to going into Photoshop.

That's where PhotoKit Sharpener 2.0 will dwell...creative sharpening for effect...

BTW, using an edge mask for capture sharpening is pretty much a baseline standard...PhotoKit Sharpener give you the ability to use the Expert mode that preserves the edge masks for post adjustment...and while ACR & LR's sharpening is based on Bruce's sharpening principals, that aren't based on our algorithms (while the output sharpening is). However, the edge mask in ACR & LR is a direct result of Bruce's research. Pretty darn impressive that ACR & LR can parametrically do about a 20 step process in Photoshop with the adjustment of a single slider (with an optional preview of the mask).

Really, anybody who isn't impressed by that has their head up their arse...(or doesn't have a clue about the importance of edge masks)

:~)
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: BartvanderWolf on February 12, 2010, 07:47:31 PM
Quote from: Schewe
Really, anybody who isn't impressed by that has their head up their arse...(or doesn't have a clue about the importance of edge masks)

:~)

On a related note, anyone who doesn't use a type of deconvolution restoration for capture sharpening is dwelling in the same dark confines ... (and noise obviously shouldn't be indiscriminantly sharpened during that restoration either) :~).

Cheers,
Bart
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Mark D Segal on February 12, 2010, 07:53:12 PM
Quote from: BartvanderWolf
On a related note, anyone who doesn't use a type of deconvolution restoration for capture sharpening is dwelling in the same dark confines ... (and noise obviously shouldn't be indiscriminantly sharpened during that restoration either) :~).

Cheers,
Bart

Perhaps you understand the LR workflow - not sure - but just to remind - it doesn't matter in LR what adjustments you make in which order, because when you "render" the image the program processes them all in correct sequence "under the hood". So you can noise-reduce and capture sharpen or capture sharpen and noise reduce - doesn't matter - the program will handle them correctly so as not to sharpen the noise. It's a "smart program".
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: BartvanderWolf on February 12, 2010, 08:33:22 PM
Quote from: Mark D Segal
Perhaps you understand the LR workflow - not sure - but just to remind - it doesn't matter in LR what adjustments you make in which order, because when you "render" the image the program processes them all in correct sequence "under the hood". So you can noise-reduce and capture sharpen or capture sharpen and noise reduce - doesn't matter - the program will handle them correctly so as not to sharpen the noise. It's a "smart program".

Hi Mark,

Yes, I understand the LR sequence of events. I also do like the parametric approach, some adjustments may cancel out at certain luminosity levels, in which case one should avoid introducing roundiing inaccuracies early in the processing chain of events. Noise control should be an integral part of sharpening (which could under circumstances mean that noise reduction is exclusively restricted to the sharpened areas, but it could also have an overall effect).

Nevertheless, edge contrast/acutance boosting shouldn't be confused with real sharpening when it produces better visual results.

Cheers,
Bart
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Mark D Segal on February 12, 2010, 10:35:21 PM
Quote from: BartvanderWolf
Hi Mark,

Yes, I understand the LR sequence of events. I also do like the parametric approach, some adjustments may cancel out at certain luminosity levels, in which case one should avoid introducing roundiing inaccuracies early in the processing chain of events. Noise control should be an integral part of sharpening (which could under circumstances mean that noise reduction is exclusively restricted to the sharpened areas, but it could also have an overall effect).

Nevertheless, edge contrast/acutance boosting shouldn't be confused with real sharpening when it produces better visual results.

Cheers,
Bart

"......when it produces better visual results" is exactly the problem. I've yet to see it, so I'm not convinced.

You say "noise control should be an integral part of sharpening..............". Where does this idea come from? Please explain and mention any authoritative references, because the way I'm understanding it - unless I'm misunderstanding it - this is totally contrary to everything I've ever been told or experienced about the relationships between measures to reduce noise and those to increase acutance. The standard approach and established advice is to NOT sharpen noise, hence if working outside of LR, reduce noise, then sharpen. The main relationship between them that I'm familiar with is that depending on the strength of the noise reduction, some additional accutance sharpening may be helpful to counteract excessive smoothing.
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: BartvanderWolf on February 13, 2010, 12:33:07 AM
Quote from: Mark D Segal
"......when it produces better visual results" is exactly the problem. I've yet to see it, so I'm not convinced.

You say "noise control should be an integral part of sharpening..............". Where does this idea come from? Please explain and mention any authoritative references, because the way I'm understanding it - unless I'm misunderstanding it - this is totally contrary to everything I've ever been told or experienced about the relationships between measures to reduce noise and those to increase acutance.

Hi Mark,

Perhaps there is a misunderstanding. Sharpening noise is counterproductive, one'll probably have to reduce it afterwards. So when I say "noise control" I meant sharpening the image content while keeping/reducing the noise component of the image in control. One common method is the adaptive Richardson Lucy restoration method, but there are others by now.

Quote
The standard approach and established advice is to NOT sharpen noise, hence if working outside of LR, reduce noise, then sharpen. The main relationship between them that I'm familiar with is that depending on the strength of the noise reduction, some additional accutance sharpening may be helpful to counteract excessive smoothing.

Ah, but then we're already compensating for things lost. I'm talking about preventing things from getting lost.

Cheers,
Bart
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Schewe on February 13, 2010, 01:00:40 AM
Quote from: BartvanderWolf
On a related note, anyone who doesn't use a type of deconvolution restoration for capture sharpening is dwelling in the same dark confines ...


Yeah, well I would consider deconvolution sharpening a sharpening for effect...

You tell me what the PSF is for a Canon 24-105mm lens is at 48mm and I might sit up an listen....

The problem with the advocates of the deconvolution kernel type of sharpening is that in practice, they CAN'T provide a point spread function worth a crap.

Yes, if you know the EXACT method of blurring and can program the EXACT opposite effect in sharpening then you can indeed turn fuzzy crap out of the Hubble telescope into usable images.

In reality all the theoretical hocus-pocus regarding deconvolution is just that...theoretical applications of algorithms that don't get too far off the ground in real life photographic applications.

Countering the effects of AA filters and lens induced softness ain't gonna happen with arbitrary PFS (point spread functions).

When you get the key to the universe, let me know (I'll bet some SOB will change the lock while you ain't looking).
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: ErikKaffehr on February 13, 2010, 01:09:29 AM
Hi,

Bart is an image processing guru, as far as I understand. I'm pretty sure that he has a point. On the other hand the people behind LR/ACR/PS and PKS are no beginners either. I got the impression that the late Bruce Fraser did look at deconvolution based sharpening and did not find any real advantage.

In a sense it's similar to 'uprezzing' it is well accepted that methods like Lanzsos introduce less artifacts than other upscaling methods. Eric "Madman" Chen and his colleagues tested around 30 different methods but still came up with the present one in LR as the best compromise.

I used Focus Magic myself, and liked it a lot. I have two issues with it:

It doesn't work on Intel Macs
It doesn't fit the parametric workflow in ACR

An additional problem with Focus Magic is it seems that development has stopped on it.

A few other comments. Deconvolution uses something called Point Spread Function (PSF). I presume that Focus Magic assumes a PSF typical of slight defocus. Optimally, the PSF would include both defocus and the effects of the AA-filter. It may be that "Focus Fixer" uses both. In my view the capture sharpening in LR works very well, it is not really obvious to me that other methods like Focus Fixer, Focus Magic or PS Advanced Sharpening would give better results.

Also, capture sharpening is never the one we see, except at actual pixels on the computer screen. Normally the images are downsized for viewing on screen or dithered for printing. I guess that the small differences we see in capture sharpening may be lost in the process.

A final observation is that your mileage may vary. Folks working with image analysis are probably much more artifact aware than normal photographers more concerned with perception of sharpness. Eyesight may matter.

Best regards
Erik

Quote from: Mark D Segal
Perhaps you understand the LR workflow - not sure - but just to remind - it doesn't matter in LR what adjustments you make in which order, because when you "render" the image the program processes them all in correct sequence "under the hood". So you can noise-reduce and capture sharpen or capture sharpen and noise reduce - doesn't matter - the program will handle them correctly so as not to sharpen the noise. It's a "smart program".
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Schewe on February 13, 2010, 01:37:23 AM
Quote from: ErikKaffehr
Bart is an image processing guru, as far as I understand. I'm pretty sure that he has a point. On the other hand the people behind LR/ACR/PS and PKS are no beginners either. I got the impression that the late Bruce Fraser did look at deconvolution based sharpening and did not find any real advantage.


No doubt Bart is a smart guy...but the odds are I've prolly made a whole poop-load more captures and prints than he since shooting and making prints is/was my livelihood. So, I'm all about practical applications of technology and less interested in theoretical stuff (although I did get the chance to hang out at MIT and meet a bunch of really bright people doing really interesting things last year thanks to Eric).

To be clear about what Bruce did or didn't think about deconvolution sharpening, Bruce didn't think too much of the initial implementation of Smart Sharpen and the rather flimsy implementation of motion de-blurring. In fact he was less than impressed with ANY commercially available deconvolution available back when he did PhotoKit Sharpener in 2003.

Nothing about that has really changed from my point of view. Nobody has produced a viable commercial sharpening approach, other than one of the options in RAW Developer that does anything SPECIFIC with regards to sharpening.

RAW Developer DOES have a Richardson-Lucy Deconvolution alternative sharpening method. But, I've been able to essentially match the IQ of RAW Developer in a "beta" raw processor currently under development (a hint might be Lightroom 3).

So, the geeks might all point to the mystical "Deconvolution" approach and banty about stuff like the Richardson–Lucy algorithm (http://en.wikipedia.org/wiki/Richardson–Lucy_deconvolution) but until somebody can send me a link to a download for a REAL (and current) Photoshop plug-in, I'm not too interested...
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: BartvanderWolf on February 13, 2010, 02:15:16 AM
Quote from: Schewe
Yeah, well I would consider deconvolution sharpening a sharpening for effect...

You tell me what the PSF is for a Canon 24-105mm lens is at 48mm and I might sit up an listen....

The problem with the advocates of the deconvolution kernel type of sharpening is that in practice, they CAN'T provide a point spread function worth a crap.

Hi Jeff, I've come to know you as a person who likes to play hard ball, so allow me to respond likewise

Too bad, but apparently you've not being paying attention to developments in scientific research (admittedly not everyone's cup of thea). Many moons ago, several years actually, there have been successful attempts to characterize the Point Spread Function (PSF), across the image (AKA spatially variant PSFs), automatically.

Quote
Yes, if you know the EXACT method of blurring and can program the EXACT opposite effect in sharpening then you can indeed turn fuzzy crap out of the Hubble telescope into usable images.

No, it doesn't require to know the EXACT PSF a priory. As the simple FocusMagic approximation of several years ago already proved, it can be successfully determined automatically and, by trial and error, improved upon for specific regons in the image plane.
I do appreciate that you've gone throught the effort of looking up what the RL restoration is about (Hubble is one area), but that's before the adaptive version, and way before the improved versions were even mentioned in research.

BTW, a kind suggestion, please do gently kick people like Chris Cox's behind if he's still operating somewhere in Adobe's code optimalization's arena and has any influence on future developments. I've exchanged some Usenet suggestions with him when he still resisted HDR tonemapping in Photoshop, he seemed to be quite conformative of the status quo, not innovative.

Quote
In reality all the theoretical hocus-pocus regarding deconvolution is just that...theoretical applications of algorithms that don't get too far off the ground in real life photographic applications.

Au contraire mon ami. As an example of (by now ancient) technology, please look at http://www.mathworks.com/access/helpdesk_r13/help/toolbox/images/deblurr8.html (http://www.mathworks.com/access/helpdesk_r13/help/toolbox/images/deblurr8.html), not theoretical at all (even Photoshop has reluctantly adopted something vagely similar (but less effective) in its Smart Sharpen filter). There are many more examples, but I'm not sure if people are open minded enough to digest them. Theoretical? I do such restorations all the time, it's even been part of a free Raw converter called RawTherapee (http://www.rawtherapee.com/?mitem=2) for some time, and I would also welcome some proactive movements from the established industry, instead of dragging behind.

Quote
Countering the effects of AA filters and lens induced softness ain't gonna happen with arbitrary PFS (point spread functions).

The AA-filter, even when combined with the theoretical diffraction (of a perfectly round aperture) used to take the image, is one of the simplest effects to restore. It's the spatial variation across the image plane that's going to challenge some of the coding dinosaurs.

Quote
When you get the key to the universe, let me know (I'll bet some SOB will change the lock while you ain't looking).

Nice try, but no sigar. I'm not a person to get intimidated by reputation alone. On the contrary, I'm much easier to get along with without (attempted) intimidation or ridicule ... There is no need for a key to the universe, just getting up to speed with it will do ...

Don't get me wrong, I do appreciate what Bruce and you have achieved, but let's not stick to that and let's collectively move on to the next level, please. It's overdue for some time.

Cheers,
Bart
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: BartvanderWolf on February 13, 2010, 02:39:16 AM
Quote from: ErikKaffehr
Hi,

Bart is an image processing guru, as far as I understand.

Not really, although I've been involved in (amongst others) scientific imaging for more than 30 years by now, I'm also a professional photographer by education.

Quote
I'm pretty sure that he has a point. On the other hand the people behind LR/ACR/PS and PKS are no beginners either. I got the impression that the late Bruce Fraser did look at deconvolution based sharpening and did not find any real advantage.

That may be part of the problem. While I respect the achievements of Bruce at all, I'm not that pleased with the slow down in progess of commercially available solutions for photographers that need to make a living, or even for advanced amateurs.

Quote
In a sense it's similar to 'uprezzing' it is well accepted that methods like Lanzsos introduce less artifacts than other upscaling methods. Eric "Madman" Chen and his colleagues tested around 30 different methods but still came up with the present one in LR as the best compromise.

There, unfortunately, is not a single best method (image content may dictate a different method). Lanczos windowed Sinc is very good at downsampling, although Sinc variants can be successful at upsampling as well.

Quote
I used Focus Magic myself, and liked it a lot. I have two issues with it:

It doesn't work on Intel Macs
It doesn't fit the parametric workflow in ACR

An additional problem with Focus Magic is it seems that development has stopped on it.

It seems to have stopped, maybe something will happen in the future, but I'm mot holding my breath.

Quote
A few other comments. Deconvolution uses something called Point Spread Function (PSF). I presume that Focus Magic assumes a PSF typical of slight defocus. Optimally, the PSF would include both defocus and the effects of the AA-filter. It may be that "Focus Fixer" uses both. In my view the capture sharpening in LR works very well, it is not really obvious to me that other methods like Focus Fixer, Focus Magic or PS Advanced Sharpening would give better results.

Also, capture sharpening is never the one we see, except at actual pixels on the computer screen. Normally the images are downsized for viewing on screen or dithered for printing. I guess that the small differences we see in capture sharpening may be lost in the process.

Good points, but what about upsampling, or downsampling without aliasing artifacts (unlike in PS Bicubic 'sharper'). Why does a program like Qimage produce better output quality than Photoshop?

Quote
A final observation is that your mileage may vary. Folks working with image analysis are probably much more artifact aware than normal photographers more concerned with perception of sharpness. Eyesight may matter.

True, although (after a considererable time) the establishment cannot keep denying the progress that's been made despite of them ...

Cheers,
Bart
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Schewe on February 13, 2010, 02:45:22 AM
Quote from: BartvanderWolf
The AA-filter, even when combined with the theoretical diffraction (of a perfectly round aperture) used to take the image, is one of the simplest effects to restore.

Then why has nobody actually coded something useful yet?

If it's "simple" to restore AA filter and lens diffraction, why hasn't some bright-boy already done that?

Oh, maybe because it's not quite so "simple"?

Quote
Too bad, but apparently you've not being paying attention to developments in scientific research (admittedly not everyone's cup of thea). Many moons ago, several years actually, there have been successful attempts to characterize the Point Spread Function (PSF), across the image (AKA spatially variant PSFs), automatically.

Uh huh...no, I don't spend a lot of time reading scientific journals. But tell me EXACTLY where all this "new" research has been taking place regarding PSFs and deconvolution image restoration and point me to a real product that is using it...

RawTherapee doesn't count cause well, I don't do Windows (nor Linux). RAW Developer is the only Mac raw processor I know of offering Richardson-Lucy Deconvolution as an optional sharpening option.

Yeah, I've wandered around and looked at the various web sites touting all manner of computational image processing to restore image sharpness. The problem is, it seems nobody is willing to actually create a commercial product and let the industry decide. It's all about theory and math (something I'm not inclined to get too far into since I'm not math genius) and so far nobody has actually PRODUCED anything...(that I know of)

As far as dealing with Chris Cox, I've known Chris since way before he joined Adobe...he can be a bit of a pain if you fail to PROVE your point to him successfully. As far as HDR tone  mapping, you might be pleasantly surprised at the changes made in the "next" version of Photoshop.

With regards to image sharpening, I'm ALWAYS willing to listen and learn. But the ultimate arbiter of what ends up in Camera Raw (and the ACR pipeline for Lightroom) is Thomas Knoll. If you can't move him, you can't move  forward...ironically, we have somebody who does a wonderful job working with Thomas here in our ranks, our own Eric Chan (MadManChan).

If you can convince Eric of something, he does have Thomas' ear (course I tend to be able to move both Thomas and Eric myself sometimes).

All the theoretical deconvolution stuff has never panned out in practical applications that I'm aware of. Sorry, it simply doesn't move me to any useful degree.

Again, if you can point to anything current that WORKS, let me know...
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: hubell on February 13, 2010, 12:15:47 PM
I recently ran some medium format digital files through Raw Developer using the Richardson-Lucy Deconvolution sharpening tool. I then ran the same files through PK Capture Sharpen, CS4 Smart Sharpen and Hasselblad Phocus. I was blown away by the Raw Developer sharpening; the combination of exceptional sharpness with a natural look. I could not get close with the other tools. Does anyone offer a CS4 plug-in using the Richardson-Lucy Deconvolution technology?
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: joofa on February 13, 2010, 02:26:48 PM
Quote from: BartvanderWolf
There, unfortunately, is not a single best method (image content may dictate a different method). Lanczos windowed Sinc is very good at downsampling, although Sinc variants can be successful at upsampling as well.

It would appear to me that a key factor is not considered in many typical sharpening operations: how to maintain a "best" sharpening while downsampling using some filter and later upsampling for a particular output device using some upsampling method. However, if the output upsampling, in case it is required, is known, there is hope.

Laczos is a good filter for downsampling, if we just stop at downsampling. However, if we are going to further stretch an image by upsampling in an output process then what is the situation? If the output reconstruction process is known then one can do a better job at keeping a sharpened image while downsampling+later upsampling. For e.g., say given an input image I downsample to half the size using Lanczos and, then, later upsample by factor 2, say, by linear interpolation, then how does the image sharpening get affected in such operation compared to an "optimized" filter (in min. mean square error terms) that does downsampling by factor 2 + later linear upsampling by factor 2.

I derived such an "optimal" filter for downsampling by factor 2 and later linear interpolation by factor 2. And the frequency response of this operation is shown below:

(http://www.djjoofa.com/data/images/downlinupsample2x2.jpg)

Note that response near Nyquist in the image above rises, before falling down, which causes sharpening, and the amount by which an image is sharpened was calculated to give the best response with later linear interpolation. Note that this "optimal" response includes an overall low pass operation, as the theory of downsampling requires, however, interestingly, in addition to including low pass effect, it also has a sharpening effect as it starts rising before Nyquist.

Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: bjanes on February 14, 2010, 09:15:12 AM
Quote from: Schewe
Yeah, well I would consider deconvolution sharpening a sharpening for effect...
Actually, deconvolution is image restoration, not sharpening. The differences may seem academic, but the essential difference is that deconvolution actually puts misplaced pixels back to where they should be, truly increasing detail, while sharpening using the unsharp mask and other techniques merely creates the illusion of sharpness by increasing edge contrast.

As all photographers know, it is best to obtain a good image in the first place and restoration would not be needed and one merely would have to employ output sharpening to get the best reproduction. If you are doing landscapes with a sturdy tripod with a Phase One P65+ using mirror lockup and a high quality prime, deconvolution might not be needed, but in much scientific imaging under difficult conditions, such methods are widely used. Their use in astronomy has been mentioned, and they are also used in microscopy (http://www.olympusmicro.com/primer/digitalimaging/deconvolution/deconvolutionhome.html).

Quote from: Schewe
You tell me what the PSF is for a Canon 24-105mm lens is at 48mm and I might sit up an listen....

The problem with the advocates of the deconvolution kernel type of sharpening is that in practice, they CAN'T provide a point spread function worth a crap.

Yes, if you know the EXACT method of blurring and can program the EXACT opposite effect in sharpening then you can indeed turn fuzzy crap out of the Hubble telescope into usable images.

In reality all the theoretical hocus-pocus regarding deconvolution is just that...theoretical applications of algorithms that don't get too far off the ground in real life photographic applications.
As Bart pointed out, one can often obtain acceptable results with some trial and error using a few basic shapes for the PSF. Examples are here (http://www.flickr.com/photos/jmzawodny/312509696/) and here (http://www.clarkvision.com/articles/image-restoration1/index.html). Roger Clark's use of the Adaptive Richardson-Lucy Iteration for an image of a fox is a real life photographic application. However R-L is not for everyone--Roger's example involved trying several PSFs by trail and error and the final computation took one and a half hours. Roger did use a Canon lens, but I don't know if it was a 24-105 at 48 mm  . However, to dismiss such techniques is akin to putting one's head in the sand and NIH (not invented here).
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Mark D Segal on February 14, 2010, 12:16:37 PM
Bill,

Some very useful insights and distinctions here. I agree - deconvolution is more for restoration than for "sharpening". And I mostly agree that the "sharpening" we do isn't focusing (that must be done in the original capture), but rather creating an illusion of sharpness by increasing edge contrast; however, I think an important additional consideration is that this increase of edge sharpening is being done to counteract the edge softening which happens as a result of both the low pass filter before the sensor and the inevitable effects of the digitization process. So in some sense it is also a "corrective", but for a different purpose than deconvolution.

It is also good that you raise the example of a Phase P65+ not needing deconvolution. That is for sure correct. Not only that, those images need only MINIMAL sharpening of the more usual variety (be it PK or others), and one needs to be very careful to apply sharpening conservatively to these images. I have recently processed a slew of them from my participation in the Phase-1 Death Valley MF workshop. Those images come straight out of the box quite clear and "sharp" - which makes sense considering that there is no low pass filter in front of that sensor, plus a bunch of other factors which make a Phase-1 back what it is.

I would also recommend that readers reflect carefully upon the veracity of the comparison reports of the kind Howard Cubell mentioned. Much is in the eye of the beholder (subjective); it may or may not be "objectively correct", because we don't have an ISO standard defining how sharp is "too sharp" in a processed photograph. What I find over-sharpened or crunchy, Howard or others may think is great stuff - not that he's wrong and I'm right, but simply because our taste and perception of what constitutes sharpness may not be the same. This came to mind as I perused a number of the images on his website BTW some striking images there Howard)  - to the extent one can tell anything reliably from relatively low-res JPEGs posted on the internet and viewed on a display. Quite some time ago in the context of another such discussion on this Forum, I too have compared actual prints of images made using Focus Magic compared with those made using PK Sharpener, re-iterating the Focus Magic settings using a range around the recommended ones, and quite frankly I couldn't produce on paper as pleasing a sharpening effect with FM as I could with PK. No doubt, others will have an opposite take on this. That's fine. So much to say there are no absolute truths here, but I remain quite persuaded that the mainstream approach to sharpening is still mainstream for good reason.

Reflecting further on the orientation some of this discussion has taken, I don't perceive any of what you call the "NIH" syndrome. Speaking of the relevant actors in the mainstream industry, you're conversing with forward-looking objective folks who don't mind looking at both the strengths and areas for improvement of what they've done before. I also place little credence in the corporate head-in-the-sand theories of the type Bart mentioned, because that too fails closer examination. Bart seems to think the "industry" is asleep and by implication perhaps he knows better than Adobe what should come next in the evolution of sharpening. The problem with this kind of statement is an implicit assumption that the engineers and mathematicians at or consulting to Adobe have some kind of vested interest against technical progress relative to their own previous work, or that they lack the competence and interest to explore alternative approaches, and that if they did indeed suffer from these conditions, Adobe's management has so little knowledge and interest to maximize shareholder value that they would simply cave-in to and indefinitely tolerate the retrograde prejudices or technical limitations of their employees. Not believable in today's competitive, performance-oriented environment - especially as one sees how aggressively Adobe goes out to buy-up expertise they don't have in-house and perceive as real value-added. But anyhow, what matters is results, not theories. Much as the discussion is interesting, we're veering off the OPs questions perhaps! (So what else is new here!)

Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Schewe on February 14, 2010, 03:45:55 PM
Quote from: Mark D Segal
Bart seems to think the "industry" is asleep and by implication perhaps he knows better than Adobe what should come next in the evolution of sharpening. The problem with this kind of statement is an implicit assumption that the engineers and mathematicians at or consulting to Adobe have some kind of vested interest against technical progress relative to their own previous work, or that they lack the competence and interest to explore alternative approaches, and that if they did indeed suffer from these conditions, Adobe's management has so little knowledge and interest to maximize shareholder value that they would simply cave-in to and indefinitely tolerate the retrograde prejudices or technical limitations of their employees.


Actually, it's laughable....

Adobe has it's fingers in a lot of the most progressive computational image processing studies from Stanford to MIT to BYU. The proof is some of the more interesting tech to go into CS3 and CS4 the most recent in CS4 with the Content Aware Scaling (originally called Seam Carving from a graduate student at MIT). Eric Chan is also an MIT product and there are several areas of research Adobe is sponsoring at MIT. Adobe even went to the effort to build new offices on the outskirts of Boston.

To say "NIH" or there's some corporate agenda against new developments and substantial image quality improvements is to ignore the rather important and substantial contributions to digital images by a fellow named Thomas Knoll. Not only did he and his brother write Photoshop 20 years ago, he wrote Camera Raw (one of the fist to break the log jams of proprietary raw file formats) and continues improving the raw processing image quality in the Lightroom processing pipeline.

I know Thomas pretty well...there is no way he would leave ANY stone unturned in the pursuit of improving image quality...the same can now be said for his understudy, Eric Chan. If you can prove to them something needs to be changed or improved, they do it. Yes, there are constraints on timing and development. Stuff doesn't happen overnite (well, sometimes it does).

I'm pretty sure that ACR 6 and Lightroom 3 releases will impress the heck out of people regarding image quality. Seriously...I think they will achieve "best of breed" status even over C1 and the manufactures' software. As I indicated, even the RAW Developer's implementation of a Richardson-Lucy deconvolution will not surpass the IQ of the next round of improvements in ACR & LR.

If somebody could prove that a Richardson-Lucy deconvolution algorithm inside of Camera Raw would be better than the current (ok, the next gen) sharpening, Thomas would not be above adding it (given adequate timing).

Yes, for some image imperfections, you can make some improvements in the image if you can find a PSF to match the image defect...

I've seen some pretty amazing image reconstructions including a guy at MIT that is working on multi-directional PSFs–the kind of camera blur where the resulting motion blur goes in multiple directions. And yes, if you were trying to read the license plate off of a fuzzy recon camera or de-blurring a terrorist's face for facial recognition of trying to remove the motion blur of a star field, all of those highly technical computational image enhancements might benefit from a more exotic de-blur algorithm regardless of where it came from...

The fact is, I'm simply not aware of anybody doing anything really useful at it relates to general photography....the kind of photography I do (which is really all I care about)

Seriously, correct me if I'm wrong...it ain't like I'm sticking my head in the sand. I'm actively looking at any and all methods of improving image quality whether it be in the shooting or the processing or printing of images...show me something interesting and useful.

(BTW, I'll bet Eric is secretly watching this thread even if he won't/shouldn't post on it–so seriously, if anybody has any useful links, post them)

:~)
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: joofa on February 14, 2010, 04:58:53 PM
Quote from: Mark D Segal
Bart seems to think the "industry" is asleep and by implication perhaps he knows better than Adobe what should come next in the evolution of sharpening. The problem with this kind of statement is an implicit assumption that the engineers and mathematicians at or consulting to Adobe have some kind of vested interest against technical progress relative to their own previous work, or that they lack the competence and interest to explore alternative approaches, and that if they did indeed suffer from these conditions, Adobe's management has so little knowledge and interest to maximize shareholder value that they would simply cave-in to and indefinitely tolerate the retrograde prejudices or technical limitations of their employees. Not believable in today's competitive, performance-oriented environment - especially as one sees how aggressively Adobe goes out to buy-up expertise they don't have in-house and perceive as real value-added. But anyhow, what matters is results, not theories.

I think Bart suggested an option that is indeed viable technically. Separate from Bart's suggestion, if Adobe is not acting upon certain research out there then it is their prerogative. Similarly, appealing to higher authorities such as MIT, Stanford, etc. does not help here. Academic research and commercializing of academic research are quite different. That is a whole new topic in itself as US universities in engineering and computer science are getting increasingly distant from industrial needs and applications. But lets not get into that topic.
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: bjanes on February 14, 2010, 05:04:42 PM
Quote from: Mark D Segal
... I too have compared actual prints of images made using Focus Magic compared with those made using PK Sharpener, re-iterating the Focus Magic settings using a range around the recommended ones, and quite frankly I couldn't produce on paper as pleasing a sharpening effect with FM as I could with PK. No doubt, others will have an opposite take on this. That's fine. So much to say there are no absolute truths here, but I remain quite persuaded that the mainstream approach to sharpening is still mainstream for good reason.
Mark,
It is always rewarding to exchange views with someone as knowledgeable and civil as yourself.  FWIW, I've also played around with FocusMagic for capture sharpening, but have found that it offers no advantage over what I can do in ACR with much less effort. I have not migrated to Lightroom and still use ACR and PS with output sharpening by PK Sharpener. Likely, the market for image restoration would be limited. Microscopists and astronomers have their own specialized software and the pro who needs the highest image quality would likely go to MFDBs. Rank amateurs are satisfied with their JPEGs. A few of us enthusiasts would like to extend what we already have and can not afford or justify a P65+. If I could double the size of my prints with My Nikon D3 using deconvolution, as Roger Clark claimed for his 8 MP 1DMII, I would gladly pay $200 for ImagesPlus or something similar. I won't hold my breath for Ver 2 of PK. And, as Roger Pointed out, there is no reason that the mainstream methods for sharpening can be applied after image restoration.

Quote from: Mark D Segal
... I don't perceive any of what you call the "NIH" syndrome. Speaking of the relevant actors in the mainstream industry, you're conversing with forward-looking objective folks who don't mind looking at both the strengths and areas for improvement of what they've done before. I also place little credence in the corporate head-in-the-sand theories ...
I was not referring to Adobe or Eric Chan, but to the forum Rottweiler. I don't know Eric personally but have exchanged a few posts with him and find him to be a gentleman and very knowledgeable and helpful. Adobe did introduce deconvolution in Photoshop some time ago and further improvements have been hinted at for the next release. I have used Photoshop since Ver 3 and have upgraded to every version since and have been pleased with enhancements in each version.




Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: hubell on February 14, 2010, 10:40:33 PM
Quote from: Mark D Segal
I would also recommend that readers reflect carefully upon the veracity of the comparison reports of the kind Howard Cubell mentioned. Much is in the eye of the beholder (subjective); it may or may not be "objectively correct", because we don't have an ISO standard defining how sharp is "too sharp" in a processed photograph. What I find over-sharpened or crunchy, Howard or others may think is great stuff - not that he's wrong and I'm right, but simply because our taste and perception of what constitutes sharpness may not be the same. This came to mind as I perused a number of the images on his website BTW some striking images there Howard)  - to the extent one can tell anything reliably from relatively low-res JPEGs posted on the internet and viewed on a display. Quite some time ago in the context of another such discussion on this Forum, I too have compared actual prints of images made using Focus Magic compared with those made using PK Sharpener, re-iterating the Focus Magic settings using a range around the recommended ones, and quite frankly I couldn't produce on paper as pleasing a sharpening effect with FM as I could with PK. No doubt, others will have an opposite take on this. That's fine. So much to say there are no absolute truths here, but I remain quite persuaded that the mainstream approach to sharpening is still mainstream for good reason.

Mark, FWIW, most of the photographs on my website are from scans of 6x7 chromes that were output sharpened with...PK! I actually found that PK does oversharpen files using the output setting for the web. I consistently had to lower the opacity of the sharpening layer returned by PK. As for your point about my observations about the R-L deconvolution sharpening tool in RD being anecdotal, you are completely right. I am hardly a scientific expert on sharpening theory, but I know what looks good to me, and I found the R-L tool to produce a nicely sharpened file that still had a very natural look. I have only compared a relatively small number of 39mp files from an H3D-39 using the deconvolution sharpening tool in Raw Developer v. other capture sharpening tools like Smart Sharpen in CS4 and the sharpening tools in Phocus and PK. Anyone can download a demo copy of Raw Developer to try the R-L deconvolution tool for himself.
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Mark D Segal on February 14, 2010, 10:55:26 PM
Quote from: hcubell
Mark, FWIW, most of the photographs on my website are from scans of 6x7 chromes that were output sharpened with...PK! I actually found that PK does oversharpen files using the output setting for the web. I consistently had to lower the opacity of the sharpening layer returned by PK. As for your point about my observations about the R-L deconvolution sharpening tool in RD being anecdotal, you are completely right. I am hardly a scientific expert on sharpening theory, but I know what looks good to me, and I found the R-L tool to produce a nicely sharpened file that still had a very natural look. I have only compared a relatively small number of 39mp files from an H3D-39 using the deconvolution sharpening tool in Raw Developer v. other capture sharpening tools like Smart Sharpen in CS4 and the sharpening tools in Phocus and PK. Anyone can download a demo copy of Raw Developer to try the R-L deconvolution tool for himself.

Howard, As Raw Developer is Mac only, not *anyone* can download it and try it. I have no experience with it - I'm on Windows, so I can't comment with any first-hand experience in this respect. But I know from reading reviews that the program has a good following.

Most interesting to hear what you tell us about your web images. Sharpening scans is a VERY delicate business. I've been through the same issues with both PK and other techniques in Photoshop alone. It starts up-stream of web output. I have found that care is needed at the Capture Sharpen stage - to select the appropriate capture sharpener, examine the results and possibly lower the opacity, then likewise with sharpening for web. I have also found for scanned media that I could often dispense with output sharpening for web after appropriate capture sharpening and downsizing for the internet.

I agree that evaluation of results depends largely on what we see - irrespective of theory, and if print is the final destination, print comparisons are all that matter.
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: ErikKaffehr on February 15, 2010, 01:26:29 AM
Hi,

I guess that capture sharpening is not only about algorithms but also about applying the algorithms. PKS and LR use several steps, like gradient masking and halo suppression, in order to protect the image. It may be that some algorithm, like RL works better than unsharp mask, but what really counts is what comes out of the printer. Getting all that right takes experimentation and experience. With PKS and LR both has been made.

I'm pretty much impressed with the sharpening in LR. I'm using Landscape as my standard preset but sometime increase amount to 95, decrease radius to 0.4 and and add some masking, leaving detail around 50.

In my view there is a tremendous amount of experience in the sharpening methods in LR, ACR and PKS. It is very well possible that it's "old thinking" but it works, never the less.

It is well possible or even probable, that better reconstruction of detail can be done using more advanced deconvolution methods based on known or estimated PSF. This is probably the case with blurred images, but capture sharpening is not about  doing the photographers work after the fact.

Best regards
Erk
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Schewe on February 15, 2010, 01:43:12 AM
Quote from: ErikKaffehr
...It may be that some algorithm, like RL works better than unsharp mask, but what really counts is what comes out of the printer. Getting all that right takes experimentation and experience. With PKS and LR both has been made.


In the end, it's all about the print...

You can dither and argue about what an image is supposed to look like on a computer display but unless the display is the final output, it don't mean shit...

The real arbiter of what is good and bad is the general user (and the general public) and how they evaluate a print. The important technology is that which actually has a practical impact. Theoretical research is just that...theoretical. No reason not to do it...big reason not to fall in love what what isn't there yet...

Again I have to caution all of you to take what is _NOW_ with a grain of salt...the elves at Adobe (wether you think they are good or evil) don't stand still. I realize the vast majority of people don't get the chance to interact and see the brilliance of Thomas or Eric...in that regard I consider myself fortunate. On the other hands, just because somebody has done a web site citing a bunch of research doesn't make it the Holly Grail.

I don't discount pure research...pure research is the work of genius in search of a reason...we need that, no question. But we also need practical tools that actually friggin' work...that's ultimately what I'm most concerned about...how to make _MY_ work better. If you don't have something to offer, kindly get the F%&CK out of the way...

Really, if you don't have anything substantial to offer, shut the F%&CK up...
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: JimGoshorn on February 15, 2010, 08:30:30 AM
Jeff,

I have a question for you on where to capture sharpen.

A while back you had written an article (as I recall) giving a method to resize a file (up to 200%) where you suggested that you should capture sharpen after you had done the resizing, followed by PK Super Sharpen, PK Super Grain and PK Output Sharpen.

Is that workflow still suggested or is it OK to capture sharpen in LR and then do the rest later on with PK Sharpener.

Thanks!

Jim
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Schewe on February 15, 2010, 12:55:24 PM
Quote from: JimGoshorn
Is that workflow still suggested or is it OK to capture sharpen in LR and then do the rest later on with PK Sharpener.

Depends...as the time has moved forward and the file size my cameras produce get bigger (1Ds MIII, P-65+) I find myself actually fighting with too much resolution at times.

But if I needed something upsampled 2x, I would prolly just set the capture sharpening in ACR/LR and either upsample in ACR or export an upsampled image from LR. Then yes, I would do the intermediate stage work of Super Sharpener, Photo Noise and whatever else helped the look of the upsampled image in Photoshop before taking the image back to Lightroom for output sharpening and printing.

The reason I really gravitate towards printing from Lightroom instead of Photoshop is the superior usability of Lightroom's Print module.

Heck, I was printing out from Photoshop yesterday for a friend...2 prints in a row I screwed up the settings either in the Photoshop dlog or the driver...pissed me off so much I imported the guy's image into Lightroom just so I could print...

:~)
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: PeterAit on February 15, 2010, 01:26:24 PM
Quote from: Schewe
In the end, it's all about the print...

You can dither and argue about what an image is supposed to look like on a computer display but unless the display is the final output, it don't mean shit...

The real arbiter of what is good and bad is the general user (and the general public) and how they evaluate a print. The important technology is that which actually has a practical impact. Theoretical research is just that...theoretical. No reason not to do it...big reason not to fall in love what what isn't there yet...

Again I have to caution all of you to take what is _NOW_ with a grain of salt...the elves at Adobe (wether you think they are good or evil) don't stand still. I realize the vast majority of people don't get the chance to interact and see the brilliance of Thomas or Eric...in that regard I consider myself fortunate. On the other hands, just because somebody has done a web site citing a bunch of research doesn't make it the Holly Grail.

I don't discount pure research...pure research is the work of genius in search of a reason...we need that, no question. But we also need practical tools that actually friggin' work...that's ultimately what I'm most concerned about...how to make _MY_ work better. If you don't have something to offer, kindly get the F%&CK out of the way...

Really, if you don't have anything substantial to offer, shut the F%&CK up...

I've got to agree with Jeff. Theory has its uses, but all too often these discussions amount to little more than mental masturbation of the "I know more about this obscure formula than you do" variety. To coin a phrase, where's the beef? This is photography, after all, and photography is a visual art. When something helps me make my art better (or easier), I'll stand up and applaud. One envisions oil painters standing around discussing the physics of brush bristles and the quantum physics of linseed oil!
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: ErikKaffehr on February 15, 2010, 02:46:46 PM
Hi,

Another way to see it....

Without the curiosity, the need to know, to invent and to find out we would not have digital photography, autofocus, silver halide photography. Nor would we have a very long life span, and earth would be able to feed a population of a few million stone age people.

Best regards
Erik



Quote from: PeterAit
I've got to agree with Jeff. Theory has its uses, but all too often these discussions amount to little more than mental masturbation of the "I know more about this obscure formula than you do" variety. To coin a phrase, where's the beef? This is photography, after all, and photography is a visual art. When something helps me make my art better (or easier), I'll stand up and applaud. One envisions oil painters standing around discussing the physics of brush bristles and the quantum physics of linseed oil!
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: dsp on February 15, 2010, 03:08:24 PM
Quote from: PeterAit
. One envisions oil painters standing around discussing the physics of brush bristles and the quantum physics of linseed oil!

Just so you know...

TED fellow using nanoparticle paint : http://www.boingboing.net/2010/02/11/ted-f...g+(Boing+Boing) (http://www.boingboing.net/2010/02/11/ted-fellow-using-nan.html?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+boingboing%2FiBag+(Boing+Boing))
Just because people don't understand the technology doesn't mean they shouldn't (or don't) use it.  They might not use the same jargon, but that is a different story.

I do high-resolution scientific image for a living, and use high and low tech image enhancements, including things like RL and maximum-likelihood estimation to get rid of the instruments response function.  I can use the same code on my photographs, but rarely do it.  I usually just do selective unsharp masking, and it is fine.  I'd be very happy if the more "modern" enhancement methods make it into new software (CSxx or LRxx or whatever), because it would be nice to have the option to do it, if desired.  But I think it depends on your needs.  When I need to have the absolute highest res image, I'll characterize the spatially (and depth) dependent PSF for a given lens, and deconvolve.  It's great, and you can see big improvements using well defined metrics, but the images aren't necessarily more aesthetically pleasing.  I have to say, for my own pictures, and most of the ones I see posted, it isn't the lack of pixel sharpness that kills them, it is the lack of sharpness in execution...

best regards, Darcy
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Schewe on February 15, 2010, 03:30:46 PM
Quote from: dsp
I have to say, for my own pictures, and most of the ones I see posted, it isn't the lack of pixel sharpness that kills them, it is the lack of sharpness in execution...


Or, to quote Ansel Adams, "There is nothing worse than a sharp image of a fuzzy concept."

:~)
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: BartvanderWolf on February 16, 2010, 10:20:09 AM
Quote from: Schewe
Depends...as the time has moved forward and the file size my cameras produce get bigger (1Ds MIII, P-65+) I find myself actually fighting with too much resolution at times.

That may have to do with a wrong premise that the ACR/Lightroom workflow 'forces' one to follow. The premise to always do Capture sharpening as a first step, IMHO, is poor practice because it increases the risk of creating aliasing artifacts when downsampling (say web publishing) is required.

Here is an example, all images are based on the original TIFF that was used to produce this full size (warning 21 MB !) JPEG sample image from a 1Ds3
http://www.xs4all.nl/~bvdwolf/temp/7640_CO40_FM1-175pct_sRGB.jpg (http://www.xs4all.nl/~bvdwolf/temp/7640_CO40_FM1-175pct_sRGB.jpg)
The image is nothing fancy, just a demonstration that sharp images can be made with a camera with an AA-filter, and that deconvolution sharpening can restore the sharpness that was reduced by the opical system (lens+aperture+AA-filter+Bayer CFA+sensel aperture). Also low contrast features like the thatched roof and gras and branches against the sky are restored to what's possible given the pixel limitations of our displays without halos and stairstepped edges.

One image without prior Capture sharpening (just a straight non-sharpened Raw conversion in Capture One), and the same image but Capture sharpened, both downsampled to 800 pixels high using the Photoshop recommended Bicubic sharper method:
[attachment=20294:7640_NoS...CSharper.jpg] [attachment=20295:7640_Cap...CSharper.jpg]
The brick walls all produce aliasing artifacts, due to the poor quality of the bicubic sharper algorithm (it's worse than simple bicubic), and the Capture sharpened image shows more prominent aliasing! This demonstrates that Capture sharpening is, despite what's suggested by some, best postponed to the final processing for output stage, or skipped alltogether.

And here is an example of what proper downsampling (and without capture sharpening) looks like (and it even compresses better with the same quality settings):
[attachment=20296:7640_NoS..._Lanczos.jpg]
Halo's are prevented, ringing is present but not noticeable at the intended size, and the brick structure still looks like a brick structure without glaring artifacts. Just like basic Digital Signal Processing (DSP) predicts, one needs to reduce/eliminate the high spatial frequency content before downsampling, instead of boosting it's amplitude.

One can only hope that the future will bring better Photoshop/Lightroom tools, but as long as they are based on the wrong premises, I'm not going to hold my breath.

Cheers,
Bart
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Samotano on February 16, 2010, 10:41:51 AM
Quote from: BartvanderWolf
That may have to do with a wrong premise that the ACR/Lightroom workflow 'forces' one to follow. The premise to always do Capture sharpening as a first step, IMHO, is poor practice because it increases the risk of creating aliasing artifacts when downsampling (say web publishing) is required.

Here is an example, all images are based on the original TIFF that was used to produce this full size (warning 21 MB !) JPEG sample image from a 1Ds3
http://www.xs4all.nl/~bvdwolf/temp/7640_CO40_FM1-175pct_sRGB.jpg (http://www.xs4all.nl/~bvdwolf/temp/7640_CO40_FM1-175pct_sRGB.jpg)
[...]
Cheers,
Bart
Isn't this more a problem of the downsampling algorithm rather than the sharpening workflow? I had the same problem which I resoloved by using Lanczos in a different softwareto downsample. I don't recall capture sharpening having much to do with it.
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Mark D Segal on February 16, 2010, 10:53:14 AM
Quote from: Samotano
Isn't this more a problem of the downsampling algorithm rather than the sharpening workflow? I had the same problem which I resoloved by using Lanczos in a different softwareto downsample. I don't recall capture sharpening having much to do with it.

I agree, there is a co-mingling of issues here. One should analyze one thing at a time for correct scientific procedure. I am doing some very elementary stuff with the images which Bart so kindly shared with us and I'll report back if I have anything useful to contribute as a result of that.
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: joofa on February 16, 2010, 12:01:43 PM
Quote from: BartvanderWolf
The brick walls all produce aliasing artifacts, due to the poor quality of the bicubic sharper algorithm (it's worse than simple bicubic), and the Capture sharpened image shows more prominent aliasing!

Hi Bart, I would tend to believe that aliasing is happening because BiCubic is normally an interpolation mechanism (upsampling) and not suited for downsampling in general because it does not include an anti-aliasing filter. I'm not privy to Photoshop's version of BiCubic (viz., BiCubic sharpner, etc.) but would like to believe that it is more or less a variation on the regular BiCubic interpolation stuff. Perhaps that is why people have such heuristics as to blur an image with, say, a Gaussian, before BiCubic downsampling, which is a non-ideal way of throwing in an anti-aliasing filter in the form a blurring Gaussian. If one downsamples with Lanczos then it includes the anti-aliasing mechanism matched to the downsampling factor.

In general straight interpolation-derived downsampling mechanisms are not streamlined for information loss inherent in a downsampling operation.
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: BartvanderWolf on February 16, 2010, 12:25:11 PM
Quote from: joofa
Hi Bart, I would tend to believe that aliasing is happening because BiCubic is normally an interpolation mechanism (upsampling) and not suited for downsampling in general because it does not include an anti-aliasing filter. I'm not privy to Photoshop's version of BiCubic (viz., BiCubic sharpner, etc.) but would like to believe that it is more or less a variation on the regular BiCubic interpolation stuff.

That's correct, BiCubic sharper is a variation on BiCubic, but it is Adobe's recommended heuristics for downsampling and I think people should be warned against the use of it. Adding sharpening before downsampling only complicates the process.

Quote
Perhaps that is why people have such heuristics as to blur an image with, say, a Gaussian, before BiCubic downsampling, which is a non-ideal way of throwing in an anti-aliasing filter in the form a blurring Gaussian. If one downsamples with Lanczos then it includes the anti-aliasing mechanism matched to the downsampling factor.

Absolutely agree. Pre-blurring the image and then using straight BiCubic (although Photoshop's isn't straight either) already gives better behaved results, but not quite as good as a e.g. Lanczos windowed Sinc does.

Quote
In general straight interpolation-derived downsampling mechanisms are not streamlined for information loss inherent in a downsampling operation.

They are not optimal indeed, but for reasons of speed(?) companies will cut corners, and the result is as shown. What's worse, users of Photoshop are not even offered an option to do it better, without resorting to homebrewn 'solutions'.

Cheers,
Bart
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Samotano on February 16, 2010, 12:57:23 PM
Going OT here for a moment... But I just don't understand why Adobe does not put something as simple as a Lanczos downsampling algorithms in the image size window (something like: Lanczos (Better for reduction)).  So many images are destined for the web that downsampling is quite a common routine.  I don't think speed is no longer an issue these days.
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Mark D Segal on February 16, 2010, 12:59:10 PM
Quote from: Mark D Segal
I agree, there is a co-mingling of issues here. One should analyze one thing at a time for correct scientific procedure. I am doing some very elementary stuff with the images which Bart so kindly shared with us and I'll report back if I have anything useful to contribute as a result of that.

I'm back (ugh! some may say - too bad   )

First, I like Bart's basic image, because it has the kind of micro-detail and frequency which lends itself to the testing one needs for drilling down on the issues discussed here.

Second, there are five things going on at the same time relative to the raw file: (a) The file format has been converted from CR2 to jpeg, which destroys a huge amount of data right from the get-go; ( the bit depth has been shrunk from 16 to 8 which destroys a lot more data - so we're starting the examination from a compromised file. © There are two kinds of downsampling, and (d) there is sharpening versus no sharpening. (e) In this particular file, there is a strange underlying phenominon with the brickwork on the windmill (only) which shows under some conditions and not others: this is a pattern of concentric bands accross the brickwork. These got created and embedded somewhere along the process between capture and processing, and, as I say, they show under some conditions but not others. I would expect they are completely absent from the original raw capture, but got introduced with one of the above-mentioned manipulations.

Starting with Bart's 25MP file, the first thing I did was to examine what shows on the display (LaCie 321 resolution 1600*1200) as a result of resampling. The first resampling I did was only to change the resolution from 300PPI to 72 PPI (quite a dramatic change, but what one would do making high-res images useable on the internet) without touching the linear dimensions. This downsampling, viewed at 100%, produced no obvious impairment of the image. Then I added to the change of resolution, a downsizing of linear dimensions from the 12*18 (roughly) Bart sent, to the (roughly 7.4*11.1 which he used in his other renditions. The combination of the change in linear dimensions with the change in resolution brought out factor (e) above.

Next, I printed (in my Epson 3800) all three of Bart's low-res JPEGs on a large sheet of Epson Exhibition Fiber paper at the same resolution as provided (72 PPI) and did absolutely no adjustments period, so as not to introduce yet more variables into the stew. Of course, the resulting print is somewhat pixellated, as expected at 72PPI. Therefore to examine for other impacts, one needs to kind of look through the pixellation, but in a way perhaps this is not so bad a thing, because it does allow one to TRULY PIXEL PEEP - and this IS what we're into here: sheer pixel-peeping. So, first I examined the two unsharpened low-res JPEGS (i.e. the one downsampled by what Bart calls "the proper way" and the one using Bicubic Sharper. Even with a 5x loupe, the printed images show no difference of quality, except for factor (e) above - the bicubic sharper image showed it quite mildly and the "proper" one didn't. That doesn't necessarily mean the "proper" one is "better" - it may in fact be less accurate, but that's unclear.

Then I compared the two images downsampled with Bi-Cubic Sharper - one capture sharpened and the other not capture sharpened. Here again, een with extreme pixel-peeping, the effect of Capture Sharpening is virtually indetectable on paper, and that is how it should be. In a multi-staged sharpening workflow, Capture sharpening is built-upon to get the final effect, it is not an end in itself.

Now, to escape from whatever the confines of pixellation, I reverted to Bart's 25MP 300PPI JPEG which has a - to us - starting file size of about 12*18, and I made a copy of it. I left the original intact, and for the copy I simply added PK Capture Sharpen Hi-res Digital Superfine (because this is a very high frequency image). I printed the two images on Epson Exhibition Fiber paper (BTW, in all sets of prints, I used Epson's highest quality settings of Super Photo and low speed, with Photoshop Manages Color and Printer Color Management OFF - took a while to do). This time, we are comparing for sharpening impact only  - and here again, even examined under the loupe - there is nothing negative, no halos, and in fact these images are pretty-well indistinguishable on paper, and that is very much what I expected also.

I've now exhausted pretty much what I could do with the materials at hand, and I've come to a provisional landing that much of this discussion is fun intellectual self-gratification, but it has very little, if any, real-world significance.
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Schewe on February 16, 2010, 01:21:47 PM
Quote from: BartvanderWolf
One image without prior Capture sharpening (just a straight non-sharpened Raw conversion in Capture One), and the same image but Capture sharpened, both downsampled to 800 pixels high using the Photoshop recommended Bicubic sharper method:


Uh huh...capture sharpened how? With what settings?

I think what this proves is NOT that capture sharpening is bad, but that a single bicubic sharper downsample of a large file is bad...

in Photoshop I do multiple bicubic downsample processes till I get close to the final needed size than do a final bicubic sharper for the last resample...or, I use Camera Raw or Lightroom to get the image close to the final needs size with a last touch of resample (often bicubic) to get the exact size...unfortunately, at this time Camera Raw's size and resolution controls suck so I would suggest Lightroom for a comparison since there you can be precise with pixel dimension...

If you want to upload the raw file I'll compare...I have no interest flailing around with a jpeg.
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: joofa on February 16, 2010, 01:33:54 PM
Quote from: Schewe
a single bicubic sharper downsample of a large file is bad... in Photoshop I do multiple bicubic downsample processes till I get close to the final needed size than do a final bicubic sharper for the last resample...

It would appear to me that multiple cascaded BiCubic operations will do the trick in a convoluted way since now in effect you are increasing the "reach" of the BiCubic operation to a larger number of pixels as opposed to some fixed number in a single downsampling operation using BiCubic. (I'm assuming that Photshop's window of pixels to work with in their version of BiCubic is fixed for a single operation.) However, it is just easier to use a single "proper" downsampling filter, say, Lanczos, applied in a single step instead of the above-said cascaded BiCubic operation.
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Schewe on February 16, 2010, 03:13:27 PM
Quote from: joofa
(I'm assuming that Photshop's window of pixels to work with in their version of BiCubic is fixed for a single operation.)


For Photoshop, yes...for Lightroom I'm pretty sure Eric's implementation of adaptive resampling is different than Photoshop's. Not sure I can say (nor know EXACTLY) what the resampling in Lightroom is doing relative to Photoshop's 3 flavors of Bicubic but I do know it's different than Photoshop's downsampling options and specifically designed to avoid ringing and interference when downsampling...
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Mark D Segal on February 16, 2010, 03:19:55 PM
Quote from: Schewe
For Photoshop, yes...for Lightroom I'm pretty sure Eric's implementation of adaptive resampling is different than Photoshop's. Not sure I can say (nor know EXACTLY) what the resampling in Lightroom is doing relative to Photoshop's 3 flavors of Bicubic but I do know it's different than Photoshop's downsampling options and specifically designed to avoid ringing and interference when downsampling...

Jeff, by "ringing", do you mean the phenominon I mentioned as point (e) in my post 53 above?
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Schewe on February 16, 2010, 03:56:38 PM
Quote from: Mark D Segal
Jeff, by "ringing", do you mean the phenominon I mentioned as point (e) in my post 53 above?


No, I don't think so...

Camera Raw (and therefor Lightroom) used to use a Lanczos variant in the resampling algorithm starting with ACR 1 through ACR 5.2 when it was changed to the hybrid bicubic variant found in ACR/LR now.

The Lanczos algorithm can introduce a ringing effect (kind of a dark line or edge interference) in some images when downsampling and it was pretty much less good (sucked) for upsampling...

The impact of this was visible not only in downsampled exports and the Web module but in the Print module of Lightroom where a really large image printed small had a tendency of breaking up on strong contrast circles and diagonals and certain frequencies of texture....at the time we thought it might have been caused by the Lightroom output sharpening but it was more a result of the resample code. But, once that got fixed, Eric also went in and fine-tuned the output sharpening even further to the point where I think it's optimal...

Which is yet another reason I really like outputting from Lightroom vs Photoshop...

Also note that great strides have been made in IQ with Lightroom 3 beta...not only has the demosiacing been enhanced but the color noise reduction and the capture sharpening has been optimized...one can also presume (although I can't say definitively due to NDA) that all the attention spent toward IQ improvements will also be seen in Lightroom 3's Luminance Noise reduction which is yet to be implemented...

Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Mark D Segal on February 16, 2010, 04:06:34 PM
Quote from: Schewe
No, I don't think so...

Camera Raw (and therefor Lightroom) used to use a Lanczos variant in the resampling algorithm starting with ACR 1 through ACR 5.2 when it was changed to the hybrid bicubic variant found in ACR/LR now.

The Lanczos algorithm can introduce a ringing effect (kind of a dark line or edge interference) in some images when downsampling and it was pretty much less good (sucked) for upsampling...

.................

You're right - this isn't the same thing that I described above.

Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: bjanes on February 16, 2010, 04:45:49 PM
Quote from: BartvanderWolf
That may have to do with a wrong premise that the ACR/Lightroom workflow 'forces' one to follow. The premise to always do Capture sharpening as a first step, IMHO, is poor practice because it increases the risk of creating aliasing artifacts when downsampling (say web publishing) is required.

Here is an example, all images are based on the original TIFF that was used to produce this full size (warning 21 MB !) JPEG sample image from a 1Ds3 http://www.xs4all.nl/~bvdwolf /temp/7640_CO40_FM1-175pct_sRGB.jpg (http://www.xs4all.nl/~bvdwolf/temp/7640_CO40_FM1-175pct_sRGB.jpg)
The image is nothing fancy, just a demonstration that sharp images can be made with a camera with an AA-filter, and that deconvolution sharpening can restore the sharpness that was reduced by the opical system (lens+aperture+AA-filter+Bayer CFA+sensel aperture). Also low contrast features like the thatched roof and gras and branches against the sky are restored to what's possible given the pixel limitations of our displays without halos and stairstepped edges.

One image without prior Capture sharpening (just a straight non-sharpened Raw conversion in Capture One), and the same image but Capture sharpened, both downsampled to 800 pixels high using the Photoshop recommended Bicubic sharper method:
[attachment=20294:7640_NoS...CSharper.jpg] [attachment=20295:7640_Cap...CSharper.jpg]
The brick walls all produce aliasing artifacts, due to the poor quality of the bicubic sharper algorithm (it's worse than simple bicubic), and the Capture sharpened image shows more prominent aliasing! This demonstrates that Capture sharpening is, despite what's suggested by some, best postponed to the final processing for output stage, or skipped alltogether.

One can only hope that the future will bring better Photoshop/Lightroom tools, but as long as they are based on the wrong premises, I'm not going to hold my breath.

Cheers,
Bart
Bart,

If you look at Bruce Fraser's original capture sharpening work flow, he sharpened for source with the unsharp filter at a small radius according to the megapixel count of the camera and amount according to the strength of the blur filter. Your deconvolution restoration also does this and more and would be considered by many to be a substitute for capture sharpening. To this first phase of capture sharpening, Bruce sharpened for image content according to the predominant frequencies of the image.

A priori, performing the restoration at an early stage in processing would make sense, since one is merely putting pixels back to where they should have been in the absence of blur filter or demosaicing artifacts and the process would not introduce sharpening halos which could cause problems in downsizing. It is not clear to me why content sharpening is needed at an early stage in the work flow.

I would be interested in the deconvolution algorithm and implementation you use and how you determine the PSP, as I would like to try deconvolution in my own work. Would the deconvolution be best applied to scene referred data (linear tone curve with no gamma) or could it be applied to a TIFF with a normal tone curve? One advantage of parametric editing in ACR and Lightroom is that bulky intermediate files are not needed, but if one uses ACR or LR and deconvolutes in a standalone program, a bulky intermediate TIFF file is needed.

Regards,

Bill
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: hubell on February 16, 2010, 09:39:28 PM
Bart, I had similar experiences with my images that I downsized as jpegs for the web at 800 ppi. Images that I thought looked properly capture sharpened became quite oversharpened downsizing with Bicubic Sharper. Not much better with "plain" Bicubic. I then read about a PS plugin called Resize Magic that I downloaded and used. Much cleaner results.  http://www.fsoft.it/imaging/en/default.htm (http://www.fsoft.it/imaging/en/default.htm) I have no idea what it does differently under the hood. Trial versions are available for both Mac and Windows.
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Mark D Segal on February 16, 2010, 09:53:35 PM
Quote from: hcubell
Bart, I had similar experiences with my images that I downsized as jpegs for the web at 800 ppi. Images that I thought looked properly capture sharpened became quite oversharpened downsizing with Bicubic Sharper. Not much better with "plain" Bicubic. I then read about a PS plugin called Resize Magic that I downloaded and used. Much cleaner results.  http://www.fsoft.it/imaging/en/default.htm (http://www.fsoft.it/imaging/en/default.htm) I have no idea what it does differently under the hood. Trial versions are available for both Mac and Windows.

Howard - something is unclear here, in the phrase "downsized as jpegs for the web at 800 ppi". Did you start or end at 800ppi, (because for the web you wouldn't want more than about 800 linear pixels total, or say something south of 100PPI with an 8 inch wide dimension)? Then there is the procedure. Normally one wouldn't "downsize as jpegs" - one would do as much as possible in 16-bit ProPhoto (downsizing, conversion of colour space and converting to 8-bit) before saving as JPEG, so that you have the maximum amount of data for handling all the adjustments for web before they need to be "JPEGed". Conversion to JPEG would be the last step before any sharpening for web, if needed. Is this your procedure?
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: joofa on February 16, 2010, 10:08:00 PM
Quote from: hcubell
I had similar experiences with my images that I downsized as jpegs for the web at 800 ppi. Images that I thought looked properly capture sharpened became quite oversharpened downsizing with Bicubic Sharper. Not much better with "plain" Bicubic.

I think the "oversharpened" look may actually be due to an aliased image since no anti-aliasing is present before BiCubic downsampling - a limitation of the interpolation based schemes used directly for downsampling. However, even such schemes should be able to provide a right kernel for downsampling if handled properly. For e.g. I took the interpolation based Keys BiCubic convolution (http://en.wikipedia.org/wiki/Bicubic_interpolation#Bicubic_convolution_algorithm) operation and derived the right anti-aliasing filter coupled to it for downsampling by a factor of 2. The calculations were done by hand quickly so there is a chance of error, however, that is the shape I got:

(http://www.djjoofa.com/data/images/key_downsample_2.jpg)

In deriving the above filter I set up the optimization problem to use the same criterion inherent in Shanon's sampling theorem: That the difference between the original and reconstructed signal obtained from the downsampled lies in the null space of the sampling operator. Note the response of the filter lies close to [-0.25 0.25] x [-0.25 0.25] for dowsampliing by a factor of 2.
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: hubell on February 16, 2010, 10:58:13 PM
Quote from: Mark D Segal
Howard - something is unclear here, in the phrase "downsized as jpegs for the web at 800 ppi". Did you start or end at 800ppi, (because for the web you wouldn't want more than about 800 linear pixels total, or say something south of 100PPI with an 8 inch wide dimension)? Then there is the procedure. Normally one wouldn't "downsize as jpegs" - one would do as much as possible in 16-bit ProPhoto (downsizing, conversion of colour space and converting to 8-bit) before saving as JPEG, so that you have the maximum amount of data for handling all the adjustments for web before they need to be "JPEGed". Conversion to JPEG would be the last step before any sharpening for web, if needed. Is this your procedure?

I start with very large 16 bit scans or digital captures. Using PS CS4, I would flatten the layers, convert to 8 bits, convert to sRGB, output sharpen, then go to Save for Web and Devices and size the file at 800ppi wide and Medium Quality. With Resize Magic, I would flatten, convert to 8 bits, convert to sRGB, output sharpen, save as a JPEG, open the JPEG and downsize with Resize Magic to 800 ppi wide.
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Schewe on February 16, 2010, 11:19:10 PM
Quote from: hcubell
...I would flatten the layers, convert to 8 bits, convert to sRGB, output sharpen, then go to Save for Web and Devices and size the file at 800ppi wide and Medium Quality...


Well, couple of problems there...first, are you SURE you convert to 8 bit and THEN convert to sRGB? If you are you are wating your 16 bit images by not converting to sRGB and THEN down to 8 bits/channel. Second, if you are sizing a large image in Save For Web, you might as well quit right there...if you are taking a large high quality image into a small  web image in a single sizing then you pretty much have given up a whole bunch of image quality right there...

You would be better off recording a web action that takes the ProPhoto RGB 16 bit, converts to sRGB, then converts to 8 bit then does several 50% bicubic followed with a bicubic sharper for the last resample to 800 pixels...
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: hubell on February 17, 2010, 08:13:04 AM
Quote from: Schewe
Well, couple of problems there...first, are you SURE you convert to 8 bit and THEN convert to sRGB? If you are you are wating your 16 bit images by not converting to sRGB and THEN down to 8 bits/channel. Second, if you are sizing a large image in Save For Web, you might as well quit right there...if you are taking a large high quality image into a small  web image in a single sizing then you pretty much have given up a whole bunch of image quality right there...

You would be better off recording a web action that takes the ProPhoto RGB 16 bit, converts to sRGB, then converts to 8 bit then does several 50% bicubic followed with a bicubic sharper for the last resample to 800 pixels...

Thanks, I will try that approach of downsampling by 50% in several bicubic downsamples and see how it compares to Resize Magic. I have been converting into sRGB from 16 bit files in DCam 4(a wide gamut space designed by Joe Holmes) before going to 8 bit and using Save for Web. You are absolutely right on the results with Save for the Web. That's why I switched to Resize Magic. (My principal "problem" with color in preparing images for my website is that it is a Flash site and the architecture is not color managed, with the result that images tend to look oversaturated on wide gamut monitors.)
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Mark D Segal on February 17, 2010, 08:42:57 AM
Quote from: Schewe
Well, couple of problems there...first, are you SURE you convert to 8 bit and THEN convert to sRGB? If you are you are wating your 16 bit images by not converting to sRGB and THEN down to 8 bits/channel. Second, if you are sizing a large image in Save For Web, you might as well quit right there...if you are taking a large high quality image into a small  web image in a single sizing then you pretty much have given up a whole bunch of image quality right there...

You would be better off recording a web action that takes the ProPhoto RGB 16 bit, converts to sRGB, then converts to 8 bit then does several 50% bicubic followed with a bicubic sharper for the last resample to 800 pixels...

Generally I agree - this is a good workflow. However I successfully use a slightly different procedure and have found it unecessary to downsample in stages. ("Success" here means the image emerges without looking crunchy, banded or over-sharpened). The procedure I'm using starting from a Canon 1Ds3 16-bit Pro-Photo layered PSD or TIFF is as follows:

1. Flatten Image
2. Resize and resample to 800 pixels maximum dimension, resolution 96 PPI and BiCubic Sharper in one operation
3. Convert to Profile: sRGB, ACE, RelCol or Perceptual RI to taste, BPC selected (critical)
4. Convert Mode to 8 bits per channel
5. Use PK Output Sharpener for Web and Multimedia 800 pixels, select frequency to suit, adjust the opacity of the Pass-through layer to taste (usually low opacities work best)
6. Flatten image
7. SAVE AS JPEG with ICC profile, Quality 8.

A  conservative application of step 5 is what requires the most care in the whole procedure.

This procedure can be automated up to and including Step 4. There is no check-stop possible in a PS Action for step 5, which must be adjusted manually to taste for each image.

Better ideas always welcome, provided they actually show real, tangible superiority - not interested in abstract theory and math unsupported by obvious superior rendition of real-world photographs.
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: bjanes on February 17, 2010, 08:53:55 AM
Quote from: Mark D Segal
Generally I agree - this is a good workflow. However I successfully use a slightly different procedure and have found it unecessary to downsample in stages. ("Success" here means the image emerges without looking crunchy, banded or over-sharpened). The procedure I'm using starting from a Canon 1Ds3 16-bit Pro-Photo layered PSD or TIFF is as follows:

1. Flatten Image
2. Resize and resample to 800 pixels maximum dimension, resolution 96 PPI and BiCubic Sharper in one operation
3. Convert to Profile: sRGB, ACE, RelCol or Perceptual RI to taste, BPC selected (critical)
4. Convert Mode to 8 bits per channel
5. Use PK Output Sharpener for Web and Multimedia 800 pixels, select frequency to suit, adjust the opacity of the Pass-through layer to taste (usually low opacities work best)
6. Flatten image
7. SAVE AS JPEG with ICC profile, Quality 8.

A  conservative application of step 5 is what requires the most care in the whole procedure.

This procedure can be automated up to and including Step 4. There is no check-stop possible in a PS Action for step 5, which must be adjusted manually to taste for each image.
Mark,

That work flow seems reasonable, but in step 3 the perceptual rendering intent is not available with matrix based profiles such as ProPhotoRGB and sRGB. Photoshop allows perceptual rendering to be checked without warning, but the rendering intent is always colorimetric. There are new ICC sRGB profiles that do have lookup tables for perceptual rendering.

Bill
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Mark D Segal on February 17, 2010, 09:27:38 AM
Thanks Bill. I generally leave it RelCol anyhow. I wasn't aware I really had no choice!

Mark
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: BartvanderWolf on February 17, 2010, 09:51:14 AM
Quote from: Samotano
Isn't this more a problem of the downsampling algorithm rather than the sharpening workflow? I had the same problem which I resoloved by using Lanczos in a different softwareto downsample. I don't recall capture sharpening having much to do with it.

Correct, a good downsampling algorithm will also catch some of the improperly boosted high spatial frequency detail, but as demonstrated, not all downsampling algorithms are good. Capture sharpening prior to downsampling doesn't make much sense and it increases the risk of introducing artfacts because there are no perfect filters.

Cheers,
Bart
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: jbrembat on February 17, 2010, 10:23:15 AM
Quote
The premise to always do Capture sharpening as a first step, IMHO, is poor practice because it increases the risk of creating aliasing artifacts when downsampling (say web publishing) is required.
Bart, Capture sharpening is essentially: recover the sharpness of the image before the AA-filter.
AA-filter is a low-pass filter that cuts frequency that is not compatible with periodicity of photo receptors.
Now for sharpening you can:
1- try to rebuild the original frequencies
2- increase locally the contrast to make the image crisper

1- is difficult as the poblem is ill-posed and conditions are to be forced to transform it in a well-posed problem.
There are studies that try to solve the problem, but results sometimes are good, sometimes are not good.
2- is more praticable but no frequencies (details) are restored, so no aliasing will be generated from this contrast increase.

Now what happen in downsizing?
You know it: the sampling theorem.
Before resampling you have to apply an AA-filter (low-pass) otherwise you get aliasing artifacts.

So, if you know that your image have to be downsized, it doesn't make sense to try to recover frequencies that will be in any case cutted.
If the image have to be used at original size (or upsampled for printing), if you can, you can try to restore high frequencies.

Jacopo


Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: BartvanderWolf on February 17, 2010, 10:43:55 AM
Quote from: Schewe
Uh huh...capture sharpened how? With what settings?

If I want to apply capture sharpening, I usually use the FocusMagic plug-in in Photoshop because it integrates nicely with my workflow. The settings I used were (cryptically) mentioned in the file name; Focusmagic=FM, settings Radius=1 and amount is 175. The settings were chosen visually from the small preview, and they can vary with the lens/aperture used, and with the focus quality (I used Live View to focus on the name shield of the windmill). No difficult determination of PSFs was required, it was just done by eye.

Quote
I think what this proves is NOT that capture sharpening is bad, but that a single bicubic sharper downsample of a large file is bad...


Well, it shows that the Adobe recommended downsampling method doesn't play well with sharpening prior to downsampling. I agree that by jumping through some hoops better results can be obtained, but why do we need to?

Quote
in Photoshop I do multiple bicubic downsample processes till I get close to the final needed size than do a final bicubic sharper for the last resample...or, I use Camera Raw or Lightroom to get the image close to the final needs size with a last touch of resample (often bicubic) to get the exact size...unfortunately, at this time Camera Raw's size and resolution controls suck so I would suggest Lightroom for a comparison since there you can be precise with pixel dimension...

Sure that will work, but it's quite a convoluted workflow to do something as common as repurposing an image for web display or thumbnail generation.

Quote
If you want to upload the raw file I'll compare...I have no interest flailing around with a jpeg.

I don't share Raw files, besides there is not much wrong with a highest quality JPEG when each 49 pixels get squeezed into a single pixel at output, especially when the mode is first changed to 16 bpc before downsampling. I also want to avoid an apples and oranges comparison between different Raw converters, such a comparison is nice for a different thread. I think the best method to compare sharpening is to base it on the same source data.

Nevertheless, for the people with adequate download bandwidth, I'll make available 2 crops from the original unsharpened (no noise reduction either) Capture One 4.0.0 conversion. They are 16bpc TIFFs converted to AdobeRGB, and each crop consists of the original unsharpened background layer, and a Focusmagic sharpened copy of that layer as an example of deconvolution sharpening. The sharpening is as is, neither masks nor blendings were used, just a simple FM filter was applied with the same settings as mentioned above. The result can of course be improved by adding an edge mask, but masking skills are not the subject of investigation here.

Here they are (ZIP compressed TIFFs, but that shouldn't be a problem for Photoshop users):
http://www.xs4all.nl/~bvdwolf/temp/7640_CO40_Crop1.tif (http://www.xs4all.nl/~bvdwolf/temp/7640_CO40_Crop1.tif)  (filesize approx. 20MB)
http://www.xs4all.nl/~bvdwolf/temp/7640_CO40_Crop2.tif (http://www.xs4all.nl/~bvdwolf/temp/7640_CO40_Crop2.tif)  (filesize approx. 30MB)

To reproduce the effects I showed earlier, just increase the canvas size to 3744 px wide by 5616 px high, and (after optional capture sharpening) resample down to 533x800 pixels to get the same dimensions as the small JPEGs above.

Happy flailing,
Bart
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: joofa on February 17, 2010, 10:51:38 AM
Separate to the discussion of where in the processing chain the capture or output sharpening should be done, I think it is abundantly clear that Photoshop has an inherent flaw in downsampling operations: -viz., using an interpolation procedure for direct downsampling without an anti-aliasing filter. It may not be terribly difficult to figure out a right downsampling kernel even with many interpolation-based approaches when used for downsampling as I mentioned in post # 63. (http://luminous-landscape.com/forum/index.php?s=&showtopic=41589&view=findpost&p=347515)

Such problematic downsampling in Photoshop results in heuristics, for e.g., using multliple BiCubic downsampling operations to "simulate" a real downsampling, throwing in a Gaussian blurr before Photoshop BiCubic downsampling, and other contrived workflows, which may result in an intermediate aliased image, which might sometimes appear artificially "sharpened". However, the problems in that intermediate image might be "concealed" as it might actually get smoothed during any number of operations done to it while going to an output, which in effect may "hide" the inherent flaw in Photoshop.  

Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: BartvanderWolf on February 17, 2010, 11:59:21 AM
Quote from: bjanes
A priori, performing the restoration at an early stage in processing would make sense, since one is merely putting pixels back to where they should have been in the absence of blur filter or demosaicing artifacts and the process would not introduce sharpening halos which could cause problems in downsizing. It is not clear to me why content sharpening is needed at an early stage in the work flow.

Hi Bill,

Me neither. Especially when one is likely to downsample, it is IMHO not good practice to boost high spatial frequency detail, and boosting lower frequency detail is potentially even more dangerous. Another discussion would be whether to capture sharpen before interpolation/magnification of the image size, or postpone it till after reaching the final output size.

Quote
I would be interested in the deconvolution algorithm and implementation you use and how you determine the PSP, as I would like to try deconvolution in my own work.

I use a couple of different ones, but FocusMagic works fine on a 32bit hardware platform. Unfortunately it is not ready for 64-bit hardware/software, and I'm not sure whether they will update. A friend of mine does have FocusMagic running on his 64-bit Windows 7 PC, but only when running the 32-bit version of Photoshop CS4. On my Vista Ultimate 64-bit system it won't install. I also use ImagesPlus 64-bit version which allows to specify the PSF (upto a 9x9 kernel) for use with e.g. the adaptive Richardson Lucy restoration or a few others. A free version of the RL algorithm can be found as an alternative sharpening tool in the RawTherapee converter, but it is not possible to define one's own PSF so I assume RT uses a Gaussian as PSF (through its radius control). RL is also implemented in MatLab.

PSF determination apparently can be done reasonably well with a Gaussian like PSF, or by eyeballing with a preview. The imaging chain consists of several different PSFs ((de-)focus+lens+aperture+AA-filter+sensel aperture) usually followed by a demosaicing operation. Convolving with so many different PSFs typically leads to something Gaussian-ish. I can characterize the PSF of my camera/lens/aperture/Raw converter combination pretty accurately with a proprietary method of mine. Of course for the most accurate restoration, an exact model (perferably spatially variant) would be prefered.

Quote
Would the deconvolution be best applied to scene referred data (linear tone curve with no gamma) or could it be applied to a TIFF with a normal tone curve? One advantage of parametric editing in ACR and Lightroom is that bulky intermediate files are not needed, but if one uses ACR or LR and deconvolutes in a standalone program, a bulky intermediate TIFF file is needed.

In principle one would be better off with deconvolution of linear gamma data, but as FocusMagic shows it can also be used on gamma adjusted data (maybe they linearize the data during the calculations, I don't know). My experience with RL in ImagesPlus shows that applying it on gamma adjusted data does already produce good results. I don't know how much of a difference it would make compared to linear gamma data (I want to keep things somewhat practical in my workflow, so I would like to avoid intermediate files as well).

Cheers,
Bart
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: BartvanderWolf on February 17, 2010, 12:11:12 PM
Quote from: hcubell
Bart, I had similar experiences with my images that I downsized as jpegs for the web at 800 ppi. Images that I thought looked properly capture sharpened became quite oversharpened downsizing with Bicubic Sharper. Not much better with "plain" Bicubic. I then read about a PS plugin called Resize Magic that I downloaded and used. Much cleaner results.  http://www.fsoft.it/imaging/en/default.htm (http://www.fsoft.it/imaging/en/default.htm) I have no idea what it does differently under the hood. Trial versions are available for both Mac and Windows.

Yes, perhaps it uses Lanczos windowed Sinc behind one of its options, but I don't know what goes on under the hood.

Cheers,
Bart
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Schewe on February 17, 2010, 04:20:53 PM
Quote from: BartvanderWolf
Well, it shows that the Adobe recommended downsampling method doesn't play well with sharpening prior to downsampling. I agree that by jumping through some hoops better results can be obtained, but why do we need to?

When you say "Adobe" you realize you are referring to a company of many, many individuals, right? There is no such thing as "An Adobe Way"...what you are referring to is really just the "Photoshop Way". What you are ignoring when lumping all of Adobe into a single entity is the Camera Raw pipeline (Camera Raw and Lightroom) as well as the Fireworks (if dealing with images for the web).

Thomas used to use a Lanczos variant but decided bicubic variants did better and thus changed them. Thomas (and Eric) look at all sorts of new tech developments for possible inclusion into Camera Raw...on the other hand, Photoshop at nearly the age of 20 (as of Fri) is a bit slower to take on new tech to replace old tech. They currently have their hands completely full doing the Mac Carbon to Cocoa API conversion...they wouldn't be interested in changing Image Size any time in the near future...

As far as jumping through hoops...you really only have to do that one time for the purposes of creating an action to run in batch mode. I can see no reason to do image by image reductions manual just for the web...or simply use Lightroom that is using a more modern reasmpling.

As for the raw file, I completely understand, but that then eliminates the possibility of testing various capture sharpening options such as Capture One, DPP and Lightroom 3 at a raw stage...
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Mark D Segal on February 17, 2010, 04:51:36 PM
Quote from: BartvanderWolf
Here they are (ZIP compressed TIFFs, but that shouldn't be a problem for Photoshop users):
http://www.xs4all.nl/~bvdwolf/temp/7640_CO40_Crop1.tif (http://www.xs4all.nl/~bvdwolf/temp/7640_CO40_Crop1.tif)  (filesize approx. 20MB)
http://www.xs4all.nl/~bvdwolf/temp/7640_CO40_Crop2.tif (http://www.xs4all.nl/~bvdwolf/temp/7640_CO40_Crop2.tif)  (filesize approx. 30MB)



Happy flailing,
Bart

Bart, I did download your raw sections, thanks, duplicated them and on the duplicate set sharpened with PK Capture and Output sharpening, then reduced the opacity of the Pass-Through Output Sharpen layer to taste. Seen at 50% and 100% screen magnification to avoid aliasing impacts, I think your Focus Magic results are fine and so are those from PK Sharpener. As I don't experience (visibly on paper) the kind of problems being reported on this thread with resampling and downsizing using Bicubic sharper, it doesn't make sense for me to intervene further on that one.
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: BartvanderWolf on February 17, 2010, 05:55:24 PM
Quote from: Schewe
When you say "Adobe" you realize you are referring to a company of many, many individuals, right? There is no such thing as "An Adobe Way"...what you are referring to is really just the "Photoshop Way". What you are ignoring when lumping all of Adobe into a single entity is the Camera Raw pipeline (Camera Raw and Lightroom) as well as the Fireworks (if dealing with images for the web).

You're right, the Photoshop recommended way it is then.

Quote
Thomas used to use a Lanczos variant but decided bicubic variants did better and thus changed them. Thomas (and Eric) look at all sorts of new tech developments for possible inclusion into Camera Raw...on the other hand, Photoshop at nearly the age of 20 (as of Fri) is a bit slower to take on new tech to replace old tech. They currently have their hands completely full doing the Mac Carbon to Cocoa API conversion...they wouldn't be interested in changing Image Size any time in the near future...

I understand the priorities, but I do wonder how on earth he was led to believe that the bicubic variants were better. Certainly not better for quality downsampling, as many have demonstrated/experienced, and as predicted by my simple zone plate test (http://www.xs4all.nl/~bvdwolf/main/foto/down_sample/down_sample.htm). It is also an easy method to test the effectivity of cascaded downsampling. Maybe he didn't want different algorithms for downsampling and interpolation/upsampling (which is common practice in the industry)?

Quote
As far as jumping through hoops...you really only have to do that one time for the purposes of creating an action to run in batch mode. I can see no reason to do image by image reductions manual just for the web...or simply use Lightroom that is using a more modern reasmpling.

Things are easier when one only needs a fixed downsampling ratio, e.g. camera file format to 800 pixels max dimension, but when one has to deal with different size source materials then the solution quickly becomes sub-optimal for e.g. batch (droplet) processing without manual intervention.

Quote
As for the raw file, I completely understand, but that then eliminates the possibility of testing various capture sharpening options such as Capture One, DPP and Lightroom 3 at a raw stage...

Maybe something for a new thread, after a non-beta version of LR3 is released, although I'd resent being 'forced' to buying/upgrading 2 different products from the same company for a single purpose (and I already use a good Raw converter). That's why I use the free ImageMagick (http://www.imagemagick.org/script/download.php) routines when I need quality downsampling, and its choice of interpolation/upsampling algorithms is also nice.

Cheers,
Bart
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Schewe on February 17, 2010, 07:18:41 PM
Quote from: BartvanderWolf
I understand the priorities, but I do wonder how on earth he was led to believe that the bicubic variants were better. Certainly not better for quality downsampling, as many have demonstrated/experienced, and as predicted by my simple zone plate test (http://www.xs4all.nl/~bvdwolf/main/foto/down_sample/down_sample.htm). It is also an easy method to test the effectivity of cascaded downsampling. Maybe he didn't want different algorithms for downsampling and interpolation/upsampling (which is common practice in the industry)?


Thomas (and really Eric Chan in the case of the ACR pipeline resampling) only implements new things after extensive testing...they don't do things by accident nor simply because it's either easier or cheaper. I was somewhat involved in testing the resampling because the output sharpening in LR 2 and ACR 5 was impacted by the resample code.

Unless you've done extensive tests using either Lightroom 2.3 or Camera Raw 5.3 then you are not judging what I consider to be optimal resampling of raw files (although again, I don't like the crude size and resolution controls in Camera Raw).
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: jbrembat on February 18, 2010, 04:35:11 AM
Quote from: BartvanderWolf
You're right, the Photoshop recommended way it is then.



I understand the priorities, but I do wonder how on earth he was led to believe that the bicubic variants were better. Certainly not better for quality downsampling, as many have demonstrated/experienced, and as predicted by my simple zone plate test (http://www.xs4all.nl/~bvdwolf/main/foto/down_sample/down_sample.htm). It is also an easy method to test the effectivity of cascaded downsampling. Maybe he didn't want different algorithms for downsampling and interpolation/upsampling (which is common practice in the industry)?



Things are easier when one only needs a fixed downsampling ratio, e.g. camera file format to 800 pixels max dimension, but when one has to deal with different size source materials then the solution quickly becomes sub-optimal for e.g. batch (droplet) processing without manual intervention.



Maybe something for a new thread, after a non-beta version of LR3 is released, although I'd resent being 'forced' to buying/upgrading 2 different products from the same company for a single purpose (and I already use a good Raw converter). That's why I use the free ImageMagick (http://www.imagemagick.org/script/download.php) routines when I need quality downsampling, and its choice of interpolation/upsampling algorithms is also nice.

Cheers,
Bart
Bart, you are on the wrong way.
The problem, on downsizing, is not the interpolation quality:
to avoid aliasing image have to be filtered before size reduction.


In any case it's true that Adobe is not very smart on resampling.

Jacopo


Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: BartvanderWolf on February 18, 2010, 05:30:45 AM
Quote from: Schewe
Unless you've done extensive tests using either Lightroom 2.3 or Camera Raw 5.3 then you are not judging what I consider to be optimal resampling of raw files (although again, I don't like the crude size and resolution controls in Camera Raw).

Hi Jeff,

So then, how does a downsample from 5616 to 800 pixels high look with and without prior (capture) sharpening?
I've supplied 2 crops, both with and without sharpening, so that should be easy to test for those with Lightroom 2.3 or Camera Raw 5.3.

I encourage everybody to conduct the test themselves (Crop1 is probably most challenging) and compare the result with the Photoshop bicubic sharper samples I've already supplied earlier. As suggested, in Photoshop just increase the canvas of the downloaded crop to 5616 pixels high and 3744 pixels wide, or alternatively use the full size sharpened JPEG, and import that into ACR 5.3 as a raw or use LR 2.3 and try to downsample. I'm looking forward to the results and procedure used.

Cheers,
Bart
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: BartvanderWolf on February 18, 2010, 05:54:51 AM
Quote from: jbrembat
Bart, you are on the wrong way.
The problem, on downsizing, is not the interpolation quality:
to avoid aliasing image have to be filtered before size reduction.

Hi Jacopo,

I disagree, the problem is very much the interpolation quality, which should use proper filters (or even offer a choice for different image content).

Here I'm specifically challenging the conventional mantra that one always needs to (capture) sharpen at the original size before output sharpening at the final size. Without the proper precautions such as the use of a good resampling algorithm (which automatically pre-filters the proper high spatial frequencies), pre-sharpening does not help. Of course pre-blurring would help, but first sharpening and then needing to preblur doesn't look like an efficient workflow and even more troublesome in finding the correct blur amount. Besides, the question remains, how to blur without losing too much resolution in the end result? A good filter is not available in the toolset, so one needs a better method/algorithm. Does Lightroom produce better results than Photoshop?

Another challenge is how to capture sharpen without creating something that hurts the interpolated/enlarged output. Regular sharpening techniques require a lot of attention to avoid halo creation and don't improve resolution but increase edge contrast, deconvolution restoration does much better. We don't want to enlarge artifacts, do we?

Cheers,
Bart
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: jbrembat on February 18, 2010, 08:36:04 AM
Quote from: BartvanderWolf
Hi Jacopo,

I disagree, the problem is very much the interpolation quality, which should use proper filters (or even offer a choice for different image content).

Here I'm specifically challenging the conventional mantra that one always needs to (capture) sharpen at the original size before output sharpening at the final size. Without the proper precautions such as the use of a good resampling algorithm (which automatically pre-filters the proper high spatial frequencies), pre-sharpening does not help. Of course pre-blurring would help, but first sharpening and then needing to preblur doesn't look like an efficient workflow and even more troublesome in finding the correct blur amount. Besides, the question remains, how to blur without losing too much resolution in the end result? A good filter is not available in the toolset, so one needs a better method/algorithm. Does Lightroom produce better results than Photoshop?

Another challenge is how to capture sharpen without creating something that hurts the interpolated/enlarged output. Regular sharpening techniques require a lot of attention to avoid halo creation and don't improve resolution but increase edge contrast, deconvolution restoration does much better. We don't want to enlarge artifacts, do we?

Cheers,
Bart
Quote
such as the use of a good resampling algorithm (which automatically pre-filters the proper high spatial frequencies)
Yes, a pre-filter must be applied. So you don't need a better resampling algorithm, you need a prefilter before resampling.
Of course this may be performed when you click on a button.
But the only way to do the job is:
1- filter the image
2- resample the filtered image (this is the resampling algorithm)

For example in this thread was said that using Lanczos interpolation you don't get aliasing, that's not true at all.
Lanczos interpolation is a windowed sinc interpolation and if no pre-filter is performed, it genarates aliasing.
Any resampling algorithm generates aliasing. Some algorithms give a smoother result that masks more artifacts, but it is not enough for strong image size reductions.

Jacopo

Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: joofa on February 18, 2010, 10:46:49 AM
Quote from: jbrembat
But the only way to do the job is:
1- filter the image
2- resample the filtered image (this is the resampling algorithm)

For example in this thread was said that using Lanczos interpolation you don't get aliasing, that's not true at all.
Lanczos interpolation is a windowed sinc interpolation and if no pre-filter is performed, it genarates aliasing.
Any resampling algorithm generates aliasing. Some algorithms give a smoother result that masks more artifacts, but it is not enough for strong image size reductions.

The prefiltering may not be seen as a separate process in downsampling. For integer downsampling ratios it automatically comes into play when the expanded downsampling kernel is used. However, for interpolation schemes when used for downsampling, such as BiCubic, it messes up producing aliasing. However, a way to avoid that is what I pointed out in post # 63 (http://luminous-landscape.com/forum/index.php?s=&showtopic=41589&view=findpost&p=347515) on how to convert a particular BiCubic interpolation procedure, derived from Keys interpolation, into a coupled downsampling kernel.
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: jbrembat on February 18, 2010, 12:06:15 PM
Quote from: joofa
The prefiltering may not be seen as a separate process in downsampling. For integer downsampling ratios it automatically comes into play when the expanded downsampling kernel is used. However, for interpolation schemes when used for downsampling, such as BiCubic, it messes up producing aliasing. However, a way to avoid that is what I pointed out in post # 63 (http://luminous-landscape.com/forum/index.php?s=&showtopic=41589&view=findpost&p=347515) on how to convert a particular BiCubic interpolation procedure, derived from Keys interpolation, into a coupled downsampling kernel.

In any case you have to filter before interpolating.
For performance reason, the filter and the interpolation may be executed first on x  and then on y. So filter have to be applied before.

Jacopo
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: BartvanderWolf on February 18, 2010, 12:14:34 PM
Quote from: jbrembat
Yes, a pre-filter must be applied. So you don't need a better resampling algorithm, you need a prefilter before resampling.
Of course this may be performed when you click on a button.
But the only way to do the job is:
1- filter the image
2- resample the filtered image (this is the resampling algorithm)

As Joofa also mentioned, "The prefiltering may not be seen as a separate process in downsampling" , a coupled kernel can be used.

Both 1. and 2. are needed, we agree on that, I consider them integral to a proper downsampling. Prefiltering without a proper downsampling algorithm will still result in poor quality results. So I maintain that a good resampling algorithm must be used.

Cheers,
Bart
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: joofa on February 18, 2010, 12:18:31 PM
Quote from: jbrembat
In any case you have to filter before interpolating.
For performance reason, the filter and the interpolation may be executed first on x  and then on y. So filter have to be applied before.

Here is the issue, and we shall keep the discussion simple for integer downsampling ratios. As the downsampling ratio increases the extent of any proper downsampling kernel increases to more and more pixels so the prefiltering is already built into this process, and you don't need any extra prefilter. On the other hand if one uses a usual interpolation-based mechanism for downsampling, then as the downsampling ratio increases your window to work with the pixels may be held constant (perhaps this is how Photoshop does it in BiCubic as Schewe has hinted above) and that is why aliasing happens, and to avoid that you use a prefilter, in such interpolation-downsampling schemes. People use heuristics in such methods on which/how prefilter to use in this situation. In post # 63  (http://luminous-landscape.com/forum/index.php?s=&showtopic=41589&view=findpost&p=347515) I mentioned that one may not have to use such heuristics and may derive an appropriate prefilter, coupled with some interpolation-downsampling mechanism, using some optimization criterion.

Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: bjanes on February 18, 2010, 01:13:33 PM
Quote from: BartvanderWolf
I use a couple of different ones, but FocusMagic works fine on a 32bit hardware platform. Unfortunately it is not ready for 64-bit hardware/software, and I'm not sure whether they will update. A friend of mine does have FocusMagic running on his 64-bit Windows 7 PC, but only when running the 32-bit version of Photoshop CS4. On my Vista Ultimate 64-bit system it won't install. I also use ImagesPlus 64-bit version which allows to specify the PSF (upto a 9x9 kernel) for use with e.g. the adaptive Richardson Lucy restoration or a few others. A free version of the RL algorithm can be found as an alternative sharpening tool in the RawTherapee converter, but it is not possible to define one's own PSF so I assume RT uses a Gaussian as PSF (through its radius control). RL is also implemented in MatLab.
Bart,

Thanks for the update. FocusMagic installed normally on my 64 bit Win 7 machine and works fine with the 32 bit version of Photoshop. I understand that MatLab is relatively expensive and is used by scientists and has a steep learning curve. R-L is also available in Iris (http://www.astrosurf.com/buil/us/iris/iris.htm), but the PSF is derived by selecting a point source (a star). With a terrestrial image lacking such a source, one could try to insert one from another image, but I haven't tried this. For less sophisticated users who can't or don't want to experiment at length with PSFs, FocusMagic looks like a good deconvolution method.

FWIW, I did a few experiments with ACR sharpening compared to FocusMagic using Imatest and images from the Nikon D3 with the 60 mm AFS f/2.8 micro. I merely used autofocus, so the focus may not be optimum but the image can be used for comparison. To keep things simple I used the ACR sharpening defaults (amount = 25, radius = 1.0 and detail = 25). For FM I experimented interactively and used a radius of 2 and amount 100. The results are shown.

Others can comment, but the essential points that I would make are as follows. One measure of aliasing is the MTF at Nyquist. It is lowest with no sharpening, but is increased with ACR and FM sharpening. The MTF in the midfrequencies is low with no sharpening, but is improved with ACR and FM sharpening, more so with the latter. The effect can be seen visually on the shown actual images.  One could try some more optimal ACR sharpening settings, but the default looked good on the preview and further experimentation is left to a later time, perhaps when the improved demosaicing and sharpening routines become available in the next version of ACR (similar to what is present in the LR beta).

Bill

[attachment=20339:003_ACR_..._YA2_cpp.png][attachment=20337:003_ACR_...BR12_cpp.
png] [attachment=20341:003_ACR_...BR12_cpp.png][attachment=20342:CompositeSh.png]
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Mark D Segal on February 18, 2010, 01:21:15 PM
Bill,

If you have the time and interest, I'd really be interested in seeing the results of these alternatives on real-world high-frequency photographs.

Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: BartvanderWolf on February 18, 2010, 02:20:25 PM
Quote from: Mark D Segal
Bill,

If you have the time and interest, I'd really be interested in seeing the results of these alternatives on real-world high-frequency photographs.

Mark,

May I suggest downloading my example crops. You'll have an unsharpened and a FocusMagic restored result, you can duplicate the unsharpened layer and apply your preferred sharpening method and compare the layers quite easily.

Cheers,
Bart
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Mark D Segal on February 18, 2010, 02:36:58 PM
Quote from: BartvanderWolf
Mark,

May I suggest downloading my example crops. You'll have an unsharpened and a FocusMagic restored result, you can duplicate the unsharpened layer and apply your preferred sharpening method and compare the layers quite easily.

Cheers,
Bart

Been there, done that.....see post #77

Cheers,

Mark
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: BartvanderWolf on February 18, 2010, 03:09:02 PM
Quote from: bjanes
Bart,

Thanks for the update. FocusMagic installed normally on my 64 bit Win 7 machine and works fine with the 32 bit version of Photoshop.

Hi Bill,

Thanks for the feedback. Guess I'm going to upgrade to Win 7 as well then ...

Quote
FWIW, I did a few experiments with ACR sharpening compared to FocusMagic using Imatest and images from the Nikon D3 with the 60 mm AFS f/2.8 micro. I merely used autofocus, so the focus may not be optimum but the image can be used for comparison. To keep things simple I used the ACR sharpening defaults (amount = 25, radius = 1.0 and detail = 25). For FM I experimented interactively and used a radius of 2 and amount 100. The results are shown.

Thanks, you just beat me to it ;-)  The results look as expected. In hindsight perhaps a slightly lower 'amount' setting for FM would have reduced the slight overshoot/halo, but this can also be addressed with a Blend-if setting of the sharpening layer. The FM radius=2 setting looks spot on, it produces as steep an edge transition as one could reasonably expect. As reference I here add how a 'perfect' edge would look:
[attachment=20346:PerfectE...pc_Y_cpp.png] [attachment=20355:PerfectE...pc_Y_cpp.png]

It's from a synthetical ideal slanted edge without any resizing or sharpening, the first one interpreted as a linear gamma image, and the second one as a gamma 0.5 (inverse gamma 2.0) image.

Cheers,
Bart
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Eric Brody on February 19, 2010, 10:44:33 PM
WOW!!! I asked what I thought was a reasonably simple question... and all hell broke loose with over 90 replies, most of which went completely over my head! And I went to 23rd grade! What an incredible forum.

I get a sense that the sharpening routines in Lightroom are the basic equivalent of Photokit except for the "creative" sharpening aspect and that output sharpening part can be done in Lightroom, or with Photokit. Is that the jist of these 90 replies?

Frankly neither do I care about nor do I understand  "deconvolution," and many of the other complexities discussed in this thread.

Most sincere thanks to everyone for all their comments. Now all I have to do is finally decide what to do. Can I learn how to sharpen in Lightroom? I hope so. It's a lot cheaper than the hundred dollars for Photokit though I have the trial and will see if I want to actually purchase it.

Eric
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Mark D Segal on February 19, 2010, 11:43:36 PM
Quote from: brodyer
WOW!!! I asked what I thought was a reasonably simple question... and all hell broke loose with over 90 replies, most of which went completely over my head! And I went to 23rd grade! What an incredible forum.

I get a sense that the sharpening routines in Lightroom are the basic equivalent of Photokit except for the "creative" sharpening aspect and that output sharpening part can be done in Lightroom, or with Photokit. Is that the jist of these 90 replies?

Frankly neither do I care about nor do I understand  "deconvolution," and many of the other complexities discussed in this thread.

Most sincere thanks to everyone for all their comments. Now all I have to do is finally decide what to do. Can I learn how to sharpen in Lightroom? I hope so. It's a lot cheaper than the hundred dollars for Photokit though I have the trial and will see if I want to actually purchase it.

Eric

Eric, I sympathize with you completely. YES, sharpen in Lightroom - it's fine! And it's not rocket-science. Here's a practical guide for how to apply it:

The image needs to be at 100% display magnification to see the effect. You get a better impression using the B&W feature which shows in the little preview window above the sliders by doing ALT-Click on the individual sliders.

Radius: Lower values give more narrow edge detail. Use values below 1 for high frequency images and values above 1 for lower frequency images. (Frequency refers to the predominance of fine edge detail).

Detail: It distinguishes edges from halos. Lower values suppress halos and allow the use of a higher Amount for mor edge sharpening; higher values accentuate halos and show more of the sharpening effect.

Masking: Increasing it blocks out more area of lesser interest for sharpening. What is masked shows as black in the little preview window with ALT pressed when you slide the Masking control.

Amount: The extent to which detail and radius are applied. Higher amounts apply them more strongly.

That's it.

The only way to master this is to examine what you are doing on the display (experiment with several types of images), note the numbers you use, and print the image. Look at the results on paper. Experiment until you develop prototypical settings which give you the appearance in print you like.

More often than not I simply use the Presets in Lightroom for sharpening - Landscape and Portrait, because on the whole, when you apply them to those respective kinds of images they really do deliver nice results.

For output sharpening in the print module - it's quite mechanical. There are only two settings, one for paper type and one for strength - again do some experiments to see which combination looks best to you ON PAPER (note the PPI setting above the sharpening should be the PPI at which you want to print). The display is not a reliable place to judge the final impact of sharpening.
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: ErikKaffehr on February 20, 2010, 03:31:30 AM
Hi,

The answer is a bit complex. There is little difference in capture sharpening and output sharpening in PKS and Lightroom. PKS is using PS-tools while Lightroom implements the same ideas using specially developed algorithms, which probably are better and definitively faster.

Also, it may be better to have a Lightroom based parametric workflow. Working in PS breaks parametric workflow and increases file sizes. Don't use PS if you don't need it.

The part where PKS really shines, in my book at least, is creative sharpening. There are nice methods for simulating depth of field, cutting haze and so on. PKS may also be nice if you work with images scanned on film.

Best regards
Erik




Quote from: brodyer
WOW!!! I asked what I thought was a reasonably simple question... and all hell broke loose with over 90 replies, most of which went completely over my head! And I went to 23rd grade! What an incredible forum.

I get a sense that the sharpening routines in Lightroom are the basic equivalent of Photokit except for the "creative" sharpening aspect and that output sharpening part can be done in Lightroom, or with Photokit. Is that the jist of these 90 replies?

Frankly neither do I care about nor do I understand  "deconvolution," and many of the other complexities discussed in this thread.

Most sincere thanks to everyone for all their comments. Now all I have to do is finally decide what to do. Can I learn how to sharpen in Lightroom? I hope so. It's a lot cheaper than the hundred dollars for Photokit though I have the trial and will see if I want to actually purchase it.

Eric
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: bjanes on February 20, 2010, 08:30:01 AM
Quote from: Mark D Segal
Bill,

If you have the time and interest, I'd really be interested in seeing the results of these alternatives on real-world high-frequency photographs.
Mark,

Here is a landscape shot with the D3 and 60 mm f/2.8 AFS at f/8 and viewed at 100%. It is not as sharp as Bart's windmill image, but I did use a tripod. It was shot at a relatively close distance and the subject distances, front to back, vary. I can't remember where I set the focus point with auto focus and I didn't use live view or mirror lockup. Nonetheless, the image is typical for what might be obtained with this camera under field conditions. I capture sharpened with ACR using Amount = 100, radius = 0.6, and Detail = 25 and with FocusMagic Radius = 2, amount = 100. I can see little difference in the images. The FM sharpening is on the left and the ACR on the right.

Regards,

Bill

[attachment=20383:CBG__081...7_fm_acr.jpg]
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: Mark D Segal on February 20, 2010, 09:32:54 AM
Quote from: bjanes
Mark,

Here is a landscape shot with the D3 and 60 mm f/2.8 AFS at f/8 and viewed at 100%. It is not as sharp as Bart's windmill image, but I did use a tripod. It was shot at a relatively close distance and the subject distances, front to back, vary. I can't remember where I set the focus point with auto focus and I didn't use live view or mirror lockup. Nonetheless, the image is typical for what might be obtained with this camera under field conditions. I capture sharpened with ACR using Amount = 100, radius = 0.6, and Detail = 25 and with FocusMagic Radius = 2, amount = 100. I can see little difference in the images. The FM sharpening is on the left and the ACR on the right.

Regards,

Bill

Bill, thanks for doing that, and yup - I agree - based on what's showing on my display I'd say they're within a pixel-peep of each other.

Cheers,

Mark
Title: sharpening-Lightroom vs PhotoKit in Photoshop or both?
Post by: VictorBushkov on June 21, 2010, 01:13:41 AM
I won't start another topic, because I have a somewhat related question. If I want to output an image for web, I downsample it through LR export dialog (since as I understand from the discussion downsampling in LR works better than in PS). In the dialog I can choose output sharpening for a screen with three options (low, standart, high). So the question is the following. Does the algorithm for output sharpening in LR take into account image content like the algorithm in PKS where it's possible to choose different image content (SuperFine, Narrow and etc)? Or it is better to downsample an image in LR without output sharpening and then sharpen the resulting image in PS with Photo Kit output sharpening?

And does ACR 6.1 use the same algorithms as LR 3?