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Author Topic: Sharpening ... Not the Generally Accepted Way!  (Read 55980 times)

Bart_van_der_Wolf

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Re: Sharpening ... Not the Generally Accepted Way!
« Reply #20 on: August 08, 2014, 06:00:10 am »

For those who think that boosting acutance is as effective as restoration by deconvolution, even after digesting this thread, I've attached 3 images. The first is a Gaussian (sigma=2) blurred star target.

The second image is that same target after restoration with deconvolution (using the Van Cittert algorithm, which would be less appropriate when the image would have contained noise).

The third is a Qimage DFS (radius2/amount 450) attempt to get as close as possible, but against deconvolution (which takes a long processing time and can be less effective if the exact PSF is not known), that's not really fair (although it does a commendable job, even with these extreme settings).

Cheers,
Bart
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PhotoEcosse

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Re: Sharpening ... Not the Generally Accepted Way!
« Reply #21 on: August 08, 2014, 06:05:07 am »

I am finding this thread both informative and thought-provoking.

One of the most common criticisms of prints made by competition judges (not that they are necessarily the ultimate arbiters of good taste) is that they are "over-sharpened".

Ideally, I suspect, the main purpose of sharpening is to compensate for deficiencies in the digital sensor and in subsequent data-processing of the captured image. Thereafter, it becomes a question of creative intent or artistic taste.

What I am happy to learn from a thread such as this is that there is an armoury of tools available to me and that I can select and use according to my intentions for any particular file.
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Mark D Segal

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Re: Sharpening ... Not the Generally Accepted Way!
« Reply #22 on: August 08, 2014, 08:05:55 am »

For those who think that boosting acutance is as effective as restoration by deconvolution,

Cheers,
Bart

This is a red herring. I, for one, think/hope I made the distinction between focus/blur and acutance issues clear enough to understand - as I mentioned - that they warrant different treatment with different tools. I'm not talking about "is as effective as" - I'm talking about aiming the right tool at the problem it is best adapted to resolve. Once readers accept I may have a point here, a lot of the discussion that's confusing these conceptually different targets of image correction can just as well evaporate. For those who are not techno-masochists and just want good results - easily - a humble suggestion: don't go to a dermatologist for a root canal: :-); use products designed for handling acutance to change image acutance; use products designed for blur (movement, focusing, DoF) to correct blur. Then it becomes sensible to make apples to apples comparisons of different software products designed for handling the same problems.
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Bart_van_der_Wolf

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Re: Sharpening ... Not the Generally Accepted Way!
« Reply #23 on: August 08, 2014, 08:29:17 am »

This is a red herring. I, for one, think/hope I made the distinction between focus/blur and acutance issues clear enough to understand - as I mentioned - that they warrant different treatment with different tools. I'm not talking about "is as effective as" - I'm talking about aiming the right tool at the problem it is best adapted to resolve. Once readers accept I may have a point here, a lot of the discussion that's confusing these conceptually different targets of image correction can just as well evaporate. For those who are not techno-masochists and just want good results - easily - a humble suggestion: don't go to a dermatologist for a root canal: :-); use products designed for handling acutance to change image acutance; use products designed for blur (movement, focusing, DoF) to correct blur. Then it becomes sensible to make apples to apples comparisons of different software products designed for handling the same problems.

Mark, I respectfully disagree. I'm using digital image processing tools, as they are commercially available to anyone willing to take a more, or less, complicated/slow/involved/automatic/whatever route to achieve his/her creative objective. The tools are all better at something different, even though they all try to achieve the same goal.

Some tools can achieve better results, but may be less convenient or even downright slow or complicated, which may, or may not, be a deciding factor to (not) use it. I'm just showing some alternatives, people can then take a informed decision that's also based on their particular preference and requirements.

Personally, I use a different tool for when larger quantities of output must be generated (perhaps with repeat-orders), compared to one-off prints. I do know what the quality trade-offs are, and what is still acceptable. It's an informed choice, not one based on ignorance or unfamiliarity.

I've only shown that there is a difference between looking sharper (by using a very well respected tool for the creation of high output quality), and actually being sharper. That's all.

Cheers,
Bart
« Last Edit: August 08, 2014, 08:30:50 am by BartvanderWolf »
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Mark D Segal

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Re: Sharpening ... Not the Generally Accepted Way!
« Reply #24 on: August 08, 2014, 08:45:25 am »

The tools are all better at something different, even though they all try to achieve the same goal.

Cheers,
Bart

Depends how you define "goal" and whether you want clear, articulated definitions that unpack the concepts - not to put too fine a point on this discussion about sharpness !!! :-)
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digitaldog

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Re: Sharpening ... Not the Generally Accepted Way!
« Reply #25 on: August 08, 2014, 11:55:16 am »

For those who are not techno-masochists and just want good results - easily - a humble suggestion: don't go to a dermatologist for a root canal: :-);

ROTFL, so true.
How many angels can dance on the head of a pin and how sharp are those pins? ;)
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Mark D Segal

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Re: Sharpening ... Not the Generally Accepted Way!
« Reply #26 on: August 08, 2014, 01:35:03 pm »


........... how sharp are those pins? ;)

OK, I was going to get into unsharp masking, but I won't go there; I think this issue has been sharpened to death   ;D
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jrsforums

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Re: Sharpening ... Not the Generally Accepted Way!
« Reply #27 on: August 08, 2014, 06:26:15 pm »

ROTFL, so true.
How many angels can dance on the head of a pin and how sharp are those pins? ;)

Is this the same as slicing the baloney too thin?  :-)
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John

Mark D Segal

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Re: Sharpening ... Not the Generally Accepted Way!
« Reply #28 on: August 08, 2014, 09:03:03 pm »

:-)

Nice to see some good-natured humour around here!
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Robert Ardill

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Re: Sharpening ... Not the Generally Accepted Way!
« Reply #29 on: August 09, 2014, 07:01:42 am »

Just in case we all get too touchy-feely, buddy-buddy ;D here's a further stirring of the nest.

I don't think I've entirely convinced anyone (myself included  :-\) that we can eliminate capture sharpening and go straight to output sharpening (I'm talking about edge-type sharpening here, not fixing the image with deconvolution or other techniques that I may not even have heard of). So I prepared this set of actions to test the hypothesis, and I hope you will try it out and give your feedback:

http://www.irelandupclose.com/customer/LL/SharpeningTest.atn

You should open an image into Photoshop from Lightroom with sharpening turned off.  There are two actions: one that resizes the image by 2 and one that resizes the image by 3.  The actions use the Camera Raw filter for all sharpening to keep things on an equal footing.

There are some Stops in the actions, just to let you know what's happening next.  Just press the continue button.

At the end there will be 4 layers.

The bottom layer (1) is the image with capture sharpening before the resize.

The second layer (2) is the image with capture sharpening after the resize.

The third layer (3) is layer 2 with output sharpening (so classical capture sharpen; resize; output sharpen).

The fourth layer (4) is the original image with output sharpening (no capture sharpening).

The basic premise is that if capture sharpening is applied with a radius of 1 before resize by x, then the capture sharpening after resize should have a radius of x.  If you compare layers 1 and 2 I think you will find that this is pretty well bang on.

The second premise is that if capture sharpening is applied with a radius of 1 and the image is then resized by x before output sharpening with a radius of x (which would give a nice sharp output but with minimum haloes ... the sort of radius I would use normally), then the same result can be obtained by doing a single output sharpening with a radius of x, but with a higher strength.  If you compare layers 3 and 4 I think you will find that there is not much between them.

Logically, I would have thought that if an equal sharpening can be achieved in one go after resizing, that it should be better to do it this way than capture sharpening, resizing, and then output sharpening.  Having said that, in the few tests I've done I can't see that one method damages the image more or less than the other.  What I do see is that there appears to be no advantage in capture sharpening first, using the sort of radii that I use.

If the output sharpening uses a much higher radius (criminal, but there you are, there are criminals out there!) then I think it would be necessary to do capture sharpening first.

Robert



« Last Edit: August 09, 2014, 07:07:26 am by Robert Ardill »
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Schewe

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Re: Sharpening ... Not the Generally Accepted Way!
« Reply #30 on: August 09, 2014, 04:53:52 pm »

Logically, I would have thought that if an equal sharpening can be achieved in one go after resizing, that it should be better to do it this way than capture sharpening, resizing, and then output sharpening.  Having said that, in the few tests I've done I can't see that one method damages the image more or less than the other.  What I do see is that there appears to be no advantage in capture sharpening first, using the sort of radii that I use.

What you are failing to consider is that capture sharpening is designed to be applied to your master image BEFORE you've actually determined at what size the image will be printed and output sharpening applied AFTER you've determined the size. That's the part of the workflow Bruce's sharpening workflow addresses. It allows one to disconnect the original size and the final print size. It's quite possible (depending on your original capture and print size) there may be no resampling needed...

And no, nothing you've written has given me any reason to alter my perception of Bruce's work in defining a sharpening workflow. Note, I may be a bit biased since I worked with Bruce to help design PhotoKit Sharpener and worked with the Lightroom engineers to incorporate PK's output sharpening in the LR Print module...

Personally, I really only use PK for Creative Sharpening and/or blurring (it has both). Most of the time I use Lightroom (or ACR) for capture sharpening (which I also consulted with the engineers to develop) and output sharpening.

Look, there are a lot of ways to skin a cat...use whatever way makes you happy. But for me, I want a repeatable and consistent way to get from capture to print without a lot of gyrations.
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Robert Ardill

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Re: Sharpening ... Not the Generally Accepted Way!
« Reply #31 on: August 09, 2014, 06:59:54 pm »

What you are failing to consider is that capture sharpening is designed to be applied to your master image BEFORE you've actually determined at what size the image will be printed and output sharpening applied AFTER you've determined the size.

Well Jeff, I'm afraid you have missed my point entirely.  What I am suggesting is that you only sharpen once (after resizing, or not resizing, as the case may be).  

I'm using words like 'Capture Sharpening' and 'Output Sharpening' in order to fit in with the terminology that seems generally accepted.

I know you have your own workflow and you're happy with that ... and you have a vested interest in this way of doing things and thinking ... but why don't you try out the action I've posted?  It will only take you a few minutes.  I would be interested in your analysis of the results (after all, you have a world of experience in this area, and your opinion - based on empirical evidence, that is - would be much appreciated!).

Robert
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Mark D Segal

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Re: Sharpening ... Not the Generally Accepted Way!
« Reply #32 on: August 09, 2014, 07:22:32 pm »

Robert, I know a lot of people will laugh when I say this, but Jeff can be a bit shy about tooting his own horn, so I shall weigh in here. Very simply put, if you haven't done so already, you need to read Chapter Two of his sharpening book. It provides a splendid explanation of the technical factors underlying the multi-stage sharpening workflow he recommends. In a nutshell, the kinds of things that need to be "sharpened for" are not the same at the input versus the output stages, therefore the algorithms need to be custom-tailored for each situation and they need to build on each other. That's the essence of the approach, and between Bruce, Jeff, and the others in the Pixelgenius group, they have spent ions of time developing and testing algorithms appropriate to each context. Having read what I have and worked with the various approaches I've tried over the years. I would be very skeptical that a one-pass approach could be systemically superior - perhaps with some photos at some resolution by happenstance, but not systemically.
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digitaldog

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Re: Sharpening ... Not the Generally Accepted Way!
« Reply #33 on: August 09, 2014, 09:47:29 pm »

I know you have your own workflow and you're happy with that ... and you have a vested interest in this way of doing things and thinking ... but why don't you try out the action I've posted?
Because of the workflow you propose. Is one output sharpening or whatever you describe optimal for ink jet, screen, halftone dot, contone output? I can't see how it could be as each output devices requires a different degree and handling of the sharpening. And it's resolution dependant. The same devices receiving a 1000x1000 pixel file need different treatment than if they are 10Kx10K. A sharpening workflow is output and resolution agnostic up until the point you know what size and device you'll output sharpen for.

Think of it this way. Say we have the best ICC profile for an Epson 3880 for Luster paper. Now change printer technology, paper, inks etc. How good is that one profile that worked so well for Luster? It isn't.

If you capture sharpen at native resolution of the capture device, or after sampling up, that's one step. But you might need to change the size considerably as well as the output device technology. One size doesn't fit all ideally. If you size and sharpen based on the output device and that sharpening is based too on the initial capture sharpening, you have a pretty flexible sharpening workflow.

Or we could go back to the days when film was scanned and output in CMYK for a specific size and press condition. That workflow worked quite well. Until you found you needed to also output a 4x5 on a film recorder. Then the initial size and color space and sharpening too, was far less than optional for that secondary use. Scan once, use many was a newer workflow in the old days when desktop imaging evolved. I believe Bruce saw that as being a far more flexible workflow and probably based his ideas on sharpening in a similar way.
« Last Edit: August 09, 2014, 09:49:19 pm by digitaldog »
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Schewe

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Re: Sharpening ... Not the Generally Accepted Way!
« Reply #34 on: August 09, 2014, 09:57:05 pm »

I know you have your own workflow and you're happy with that ... and you have a vested interest in this way of doing things and thinking ... but why don't you try out the action I've posted?

Well, because it doesn't fit in with my workflow. I guess you missed the part about capture sharpening in ACR/LR and output sharpening in LR.
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Robert Ardill

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Re: Sharpening ... Not the Generally Accepted Way!
« Reply #35 on: August 10, 2014, 06:40:47 am »

Well, because it doesn't fit in with my workflow. I guess you missed the part about capture sharpening in ACR/LR and output sharpening in LR.

Well at least Andrew gave a reason for why he believes this approach is wrong ... all you're doing is saying you can't be bothered to check it out because it doesn't fit in with your workflow.

Because of the workflow you propose. Is one output sharpening or whatever you describe optimal for ink jet, screen, halftone dot, contone output? I can't see how it could be as each output devices requires a different degree and handling of the sharpening. And it's resolution dependant. The same devices receiving a 1000x1000 pixel file need different treatment than if they are 10Kx10K. A sharpening workflow is output and resolution agnostic up until the point you know what size and device you'll output sharpen for.

If you capture sharpen at native resolution of the capture device, or after sampling up, that's one step. But you might need to change the size considerably as well as the output device technology. One size doesn't fit all ideally. If you size and sharpen based on the output device and that sharpening is based too on the initial capture sharpening, you have a pretty flexible sharpening workflow.


Of course one output sharpening isn't optimal for all papers and printers.  If it was then we would just have one button with no settings and we would all be happy little piggies.

Equally, one sharpening isn't optimal for all camera/lens/sensor combinations - especially as some have AA filters and others don't.

I think the 2-step approach (capture sharpen followed by output sharpen) is an excellent idea and has a lot of flexibility (and it makes sense for a program like PK Sharpener to be based on this approach as it caters for many different media and technologies).  

But in my case I use inkjet printers and I never want to output sharpen with a radius of more than 2 or 3 (for 'creative' sharpening, maybe, but that's another story).  On capture sharpen I will never use a radius of more than 1.  So the question I had was this: why capture sharpen with a radius of 1, then output sharpen again with a radius of 1 (for an image that has not been upsized)? Why not just sharpen once?  Then, say I upsize by 2x ... what radius should I use for output sharpen?  Well, a radius of 2 seems about right.  What about upsizing by 3?  Well, a radius of 3 seems about right.  So then the question is: if I capture sharpen with a radius of 1 and upsize by a factor of x (where x could be 1) is there an advantage in capture sharpening with a radius of 1 and then output sharpening with a radius of x, or can I just leave out the capture sharpening and sharpen once with a radius of x?

If the capture sharpening was actually fixing a flaw in the image then it would be a no-brainer: of course you would capture sharpen.  But it isn't: all it's doing is masking the flaw, and in doing so it is damaging the image.  So if you could leave out that step, which would only be magnified by subsequent (possible) resizing, that would (at least in theory) be a good idea.

Well, in the few tests I've done, it seems to me that providing you keep the sort of ratio of radii that I have mentioned, that there appears to be no better sharpening from the 2-step approach.  I also do not see that the file is damaged more by the 2-step approach (a little more haloes, but you really need to zoom in to pixel-level to see it).  So in my view it's a matter of choice.

However ... that is being VERY careful with the sharpening.  If someone over-sharpens at the Capture Sharpening stage (which I expect is very common) then the 2-step approach will be worse (easily verified).  Which isn't to say that we can't also mess up the sharpening in one step, needless to say!

Anyway, it's no big deal ... all it really points out to me is that a) we need to be very careful with sharpening, and b) I really hope to see some deconvolution image correction software soon, because then we wouldn't be having this conversation.

And ... more generally ... I don't think it's a bad thing to challenge the orthodox teachings from time to time.

Robert
« Last Edit: August 10, 2014, 06:47:07 am by Robert Ardill »
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Robert Ardill

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Re: Sharpening ... Not the Generally Accepted Way!
« Reply #36 on: August 10, 2014, 07:37:40 am »

Robert, I know a lot of people will laugh when I say this, but Jeff can be a bit shy about tooting his own horn, so I shall weigh in here. Very simply put, if you haven't done so already, you need to read Chapter Two of his sharpening book. It provides a splendid explanation of the technical factors underlying the multi-stage sharpening workflow he recommends. In a nutshell, the kinds of things that need to be "sharpened for" are not the same at the input versus the output stages, therefore the algorithms need to be custom-tailored for each situation and they need to build on each other. That's the essence of the approach, and between Bruce, Jeff, and the others in the Pixelgenius group, they have spent ions of time developing and testing algorithms appropriate to each context. Having read what I have and worked with the various approaches I've tried over the years. I would be very skeptical that a one-pass approach could be systemically superior - perhaps with some photos at some resolution by happenstance, but not systemically.

Well Mark, if Jeff tries out my little action I'll buy his book.

I had a quick look at http://www.peachpit.com/articles/article.aspx?p=1721157, as an example of capture sharpening by Jeff ... and I can tell you that I would NEVER sharpen by an amount of 60 prior to resizing, as Jeff does in this tutorial. Personally I think that's close to criminal.  Resize and then sharpen by an amount of 60, fine, not the other way around.  Since the example in the article uses Camera Raw, the sharpening is pre-resizing.

To be fair to myself, I too have spent a lot of time on this subject and I quite independently developed sharpening actions using Photoshop scripts that used very similar techniques to PK Sharpener (and also other techniques, for example using curves to generate sharpening/noise reduction masks).  A while back I even started selling the sharpening tools (and other Photoshop tools) under PixIntel.com (good name, isn't it? I still have the domain registration if someone's interested ... for a small fee  ;)) ... but I got involved in another project (and lots of people started producing this sort of software) so I dropped it.  Which isn't to say that I lost interest in the subject.

Anyway, this is not a pissing contest - but sometimes new insights can come from revisiting established beliefs.

Robert
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Mark D Segal

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Re: Sharpening ... Not the Generally Accepted Way!
« Reply #37 on: August 10, 2014, 09:40:37 am »

........... but sometimes new insights can come from revisiting established beliefs.

Robert

Very often the case and much scientific progress has been made over the centuries on the basis of that very principle. BUT in this particular instance we are not dealing with beliefs. We are dealing with algorithms that emerged from very extensive testing done by people who seriously knew/know the subject matter, and I respect that. That said, there's little in this world that can't be improved upon, but I think scientific procedure pretty much requires that you identify and demonstrate lacunae in the approach you are challenging, as a basis for trying to achieve the same objective in a better way. That is why I recommended Jeff's book to you.

I looked at the article you referenced and I didn't see, even at 200% magnification the kind of damage you consider to be "criminal" at 50 or 60 Amount setting. Personally, I don't usually find it necessary or desirable to move much beyond 45, but it can happen if I also added luminance noise reduction. However, give or take 10 or 15 point of Amount, there is something intervening called "taste". What you may consider "criminal" someone else may think is just sharp and snappy. It only gets criminal if anything has been destroyed, but if you use PK Sharpener (unflattened) or Lightroom of course everything is reversible and no pixels are destroyed.

Anyhow, reverting from the empirical to the principles, I do think it necessary to successfully challenge the correctness of the principles underlying the multi-stage sharpening workflow before accepting that a single pass approach will be SYSTEMATICALLY superior. To do this, there needs to be a combination of both reasons and a highly varied palette of extensive testing of the proposed alternative. I think it is incumbent on the author to do this research and share the results in a manner amenable to systematic evaluation.
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digitaldog

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Re: Sharpening ... Not the Generally Accepted Way!
« Reply #38 on: August 10, 2014, 10:02:07 am »

I looked at the article you referenced and I didn't see, even at 200% magnification the kind of damage you consider to be "criminal" at 50 or 60 Amount setting.
I haven't looked at this example but it's kind of important to clarity that one setting, say Amount in USM is hugely influenced by the other sliders, like Radius. The two teeter-totter between themselves so one setting specified without the other is kind of like one hand clapping.
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Re: Sharpening ... Not the Generally Accepted Way!
« Reply #39 on: August 10, 2014, 01:35:31 pm »

Very often the case and much scientific progress has been made over the centuries on the basis of that very principle. BUT in this particular instance we are not dealing with beliefs. We are dealing with algorithms that emerged from very extensive testing done by people who seriously knew/know the subject matter, and I respect that. That said, there's little in this world that can't be improved upon, but I think scientific procedure pretty much requires that you identify and demonstrate lacunae in the approach you are challenging, as a basis for trying to achieve the same objective in a better way. That is why I recommended Jeff's book to you.

I looked at the article you referenced and I didn't see, even at 200% magnification the kind of damage you consider to be "criminal" at 50 or 60 Amount setting. Personally, I don't usually find it necessary or desirable to move much beyond 45, but it can happen if I also added luminance noise reduction. However, give or take 10 or 15 point of Amount, there is something intervening called "taste". What you may consider "criminal" someone else may think is just sharp and snappy. It only gets criminal if anything has been destroyed, but if you use PK Sharpener (unflattened) or Lightroom of course everything is reversible and no pixels are destroyed.

Anyhow, reverting from the empirical to the principles, I do think it necessary to successfully challenge the correctness of the principles underlying the multi-stage sharpening workflow before accepting that a single pass approach will be SYSTEMATICALLY superior. To do this, there needs to be a combination of both reasons and a highly varied palette of extensive testing of the proposed alternative. I think it is incumbent on the author to do this research and share the results in a manner amenable to systematic evaluation.

There's nothing criminal about the sharpening in the article ... providing that this sharpening is the final sharpening (this is just my opinion, OK?).  Since the sharpening is the Capture sharpening (as per Schewe's workflow), it is the first pass before output sharpening. As such it's way too high, IMO.  "Snappy and Sharp" applies to the final sharpened image, printed or for web or for whatever medium, not for 'capture' sharpening (again, this is consistent with Schewe's workflow, I believe).

Regarding the empirical principles etc., etc., it seems to me that I have been doing a lot of testing and that I've offered not only examples, but actions for you guys to check out my suggestions . But so far no one has actually given an example testing a one-pass sharpen against a two-pass sharpen and shown that the two-pass is clearly superior, and under what conditions.

And I have certainly not suggested that a one-pass approach is SYSTEMATICALLY superior ... or even that it is superior at all.  I personally think, both from tests and from logic, that it will be better in some cases and worse in others.  If that is true (which you can check out for yourself if you're interested) then surely that is a useful bit of information?  If you knew that for, let's say, images that are upscaled, that you are better off leaving the 'capture sharpening' to after the resize, and that if you did this you would probably have some improvement in the quality of your output, would you not at least consider sharpening after resize rather than before?

Part of the problem with this whole discussion is that some of you seem to think that I am criticizing an established workflow by the gurus of the industry (including Bruce Fraser, who is no longer with us sadly).  That may to some extent be the case, but in reality it boils down to 'do you sharpen before or after resizing?'.  The reason I say that is that if you sharpen after resizing then it gives you the opportunity (if it is appropriate) to sharpen only once.

Unless the 'before resizing' corrects flaws in the original image (due, for example, to the blurring caused by the anti-aliasing filter) there seems no logical reason to apply it before resizing, and good logical reason to apply it after.  In my testing (admittedly limited) I can see no benefit to applying it before.  Since almost all of our photos will be resized before output to the web or print, it then follows that if this is true, you are better off resizing and then sharpening.

So let's say that the conclusion is that two types of sharpening are typically beneficial with the current 'sharpening' technology: one with a small radius to 'recover' fine detail, and one with a higher radius, to give the output a boosted impression of sharpness and crispness.  I think this may well be so at times.  Then, I, personally, would resize, sharpen with a small radius and then sharpen with a higher radius.  This does not fit in with the Lightroom model, because Lightroom is strictly 1st phase sharpen, followed by resize, followed by (optional) 2nd phase sharpen.

If you do not sharpen in Lightroom, then, in Photoshop, you can use one-pass sharpen where appropriate, and two-pass sharpen if you think this would be beneficial.  There is nothing that I am aware of in PK Sharpen to prevent you from doing this, since it's a Photoshop set of actions.

I would have thought that one of the great benefits of a forum like this one is that it has many very experience members, who could take a suggestion like this one and demonstrate that it is nonsense, or that it is sometimes good, or that it's the best thing since sliced bread (as a home baker I would have to question that analogy  :)).  

Robert
« Last Edit: August 10, 2014, 01:37:48 pm by Robert Ardill »
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