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Author Topic: PK Sharpener Question  (Read 33776 times)

Schewe

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Re: PK Sharpener Question
« Reply #20 on: June 23, 2013, 06:28:50 pm »

But it's not just sharpening that the guy can help us with. He also explains how most Raw converters have got it seriously wrong:


This was actually the first tutorial (if you can call it that) I saw from Guy...and Guy has it seriously wrong. He doesn't know how to use Camera Raw (nor Lightroom). Which is not atypical behavior coming from so called Photoshop Experts. When all you have is a hammer, everything looks like a nail.

Guy seems to know Photoshop (at least to a degree) but he doesn't know Camera Raw. He gets a lot wrong in this video...but the major disconnect is he doesn't really understand raw linear captures. The curve he drew on his whiteboard was more like a D Log H curve, not a raw capture curve–which is linear or a gamma curve of 1.0 or actually a 45º line from the lower left to upper right.

I'm not really sure Guy actually knows what "highlight recovery" actually is–recovery in ACR is extracting textural information from the highlights when 1 or 2 of the channels are clipped. Recovery interpolates the missing 1 or 2 channels of color data that are clipped and provides useful texture (not useless as Guy claims). Yes, recovery is an interpolation...and in PV 2003 and 2010 it could produce color problems. That was pretty much eliminated in PV 2012.

Process Version 2012 doesn't actually apply any "recovery" by default–recovery only kicks in with minus Exposure, Highlights and Whites adjustments and recovery is much improved. What PV 2012 does do is an image adaptive auto-ranging that keeps near clipping from clipping. If all three channels clip, it indicates total sensor saturation and there's nothing one can do to "recover" from that. What PV 2012 does is more a tone mapping function and not a recovery operation. Yes it has an impact on the tone mapping of highlights (and shadows BTW) and yes, PV 2012 is much less likely to clip highlight data–which is actually a good thing, not a bad thing. How you handle the mapping is up to you. Not only do you have the Basic panel for tone mapping but you have the point curve editor which give very fine control over the highlights–if you know how to use it.

The example image of the house he showed could very, very easily be controlled in PV 2012 if he bothered to touch any of the other controls than Exposure...same deal on the wedding dress shot. He makes zero effort to actually use and of the vast array of tone mapping controls that ACR provides. Well, if you don't use the controls, yeah, well, your stuff will look like Guy's. Rather poor and he does a really good job of under-selling the ACR raw processing capability. Note, the demo of the girl and violin was processed in PV 2010 in ACR (with bad recovery, but note he didn't use PV 2012 with better recovery) and compared PV 2010 in ACR to Aperture...hum, one wonders why? Ah, of course, to make ACR look as bad as he can and promote Aperture as the best raw processor on the planet.

But the worst part of Guy's approach is that he is so dismissive and disrespectful of the tools he uses and the people who develop them. If he knows so much, why isn't he more involved in the development of the tools he uses? He claims he was a "consultant" to Adobe...but I've been involved with Adobe since Photoshop version 4 (that's PS 4, not CS4) and I had never heard about Guy until this year. So, I seriously doubt that Guy has had any direct involvement in the development of Photoshop nor Camera Raw/Lightroom. In light of his dismissive attitude, I would be very surprised that Adobe would want Guy's input...

But hey, don't take my word for it...go ahead and see what Guy has to say...if you are predisposed to dislike Camera Raw or Lightroom as a raw processor, Guy is talking your language...if you are a Photoshop "expert" and you want to ignore all the research and development of smart guys like Thomas Knoll and Eric Chan, by all means, do all your work in Photoshop and buy Guy's magic actions...go right ahead...I'll keep using ACR/LR on my work followed by a touch of Photoshop when needed.
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jrsforums

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Re: PK Sharpener Question
« Reply #21 on: June 23, 2013, 07:08:11 pm »


Process Version 2012 doesn't actually apply any "recovery" by default–recovery only kicks in with minus Exposure, Highlights and Whites adjustments and recovery is much improved. What PV 2012 does do is an image adaptive auto-ranging that keeps near clipping from clipping. If all three channels clip, it indicates total sensor saturation and there's nothing one can do to "recover" from that. What PV 2012 does is more a tone mapping function and not a recovery operation. Yes it has an impact on the tone mapping of highlights (and shadows BTW) and yes, PV 2012 is much less likely to clip highlight data–which is actually a good thing, not a bad thing. How you handle the mapping is up to you. Not only do you have the Basic panel for tone mapping but you have the point curve editor which give very fine control over the highlights–if you know how to use it.



Jeff....not sure what you mean by not applying automatic "recovery"..??

Checking RAWs in RAWdigger shows that any highlight in LR greater than ~97% will have at least one channel clipped.

This is described in detail in George Jardine's article:  http://mulita.com/blog/?p=3358
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Schewe

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Re: PK Sharpener Question
« Reply #22 on: June 23, 2013, 07:40:19 pm »

He also explains how most Raw converters have got it seriously wrong:

Oooops...I never watched Guy till the bitter end till this time. I caught him in a big fat lie.

He claims Adobe didn't develop Lightroom from the ground up, he claims Adobe bought Lightroom and only to compete against Aperture after Aperture came out. Nope, sorry Guy, that is a lie plain and simple. I've been involved in the development of Lightroom from the very, very beginning and I can assure you Adobe developed it from the ground up and developed in in the same time frame that Apple developed Aperture and that Adobe didn't "copy" anything about Aperture...you can read the real Lightroom development here.

So, whatever credibility Guy may have had just went out the window...liar, liar, pants on fire :~)
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jrsforums

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Re: PK Sharpener Question
« Reply #23 on: June 23, 2013, 07:51:06 pm »

Oooops...I never watched Guy till the bitter end till this time. I caught him in a big fat lie.

He claims Adobe didn't develop Lightroom from the ground up, he claims Adobe bought Lightroom and only to compete against Aperture after Aperture came out. Nope, sorry Guy, that is a lie plain and simple. I've been involved in the development of Lightroom from the very, very beginning and I can assure you Adobe developed it from the ground up and developed in in the same time frame that Apple developed Aperture and that Adobe didn't "copy" anything about Aperture...you can read the real Lightroom development here.

So, whatever credibility Guy may have had just went out the window...liar, liar, pants on fire :~)

They did buy RawShooter about the time that LR was close to coming out.  Not sure if this was for the technology or the people...or both....but I believe the intent was to add to/improve LR.
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Schewe

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Re: PK Sharpener Question
« Reply #24 on: June 23, 2013, 09:36:05 pm »

Just to be clear...I was at an initial product meeting about what would become Lightroom in my studio in Dec, 2002. Shadowland went through many iterations in 2003-2005 with the public beta of Lightroom shipping in Jan 2006–before Adobe bought Pixmantec in June 2006. Adobe bought Pixmantec to get one specific engineer...which sadly didn't work out. There were two Rawshooter controls that were added to Lightroom; Fill Light and Vibrance although the algorithms were totally rewritten.

Yes, Aperture 1 shipped before Lightroom...but anybody with any experience in software development would know you don't create a product from scratch in a few months...in fact, I know about the guy that started working on Aperture (the same guy that worked at Adobe on Premiere Pro and left to start Final Cut Pro) and Mark, the founding engineer on Lightroom were "friends" (a couple of companies removed). They both were working on the same database driven raw processing application solution at the same time.

So, for Guy to claim Adobe "bought" Lightroom and didn't develop it from scratch is an outright lie...
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jrsforums

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Re: PK Sharpener Question
« Reply #25 on: June 23, 2013, 10:04:16 pm »

Just to be clear...I was just saying the RawShooter acquisition may have confused Guy's thoughts on LR's development.

...but I also agree that he is totally confused with what can be done in LR and the differences between PV2010 and PV2012.

He also was, unfortunately, trying to build mystery in his actions.  From some peeks in his videos it seems as if he was simply using BlendIf, Luminosity mask, and, probably, edge mask routines to do his "magic"

Much of these tutorials and actions were provide years ago, free, by Glenn Mitchell...still available, I think at "The Light's Right" site http://www.thelightsright.com/

Really enhanced luminosity masking techniques are available from Tony Kuyper http://goodlight.us/
« Last Edit: June 24, 2013, 02:48:17 am by jrsforums »
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daws

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Re: PK Sharpener Question
« Reply #26 on: June 23, 2013, 10:24:36 pm »

If you are interested in sharpening, take a look at this lesson by, probably, the world's greatest authority on the matter. His conclusion, briefly, is that most software has got it totally wrong (or worse).

http://guygowan.com/focus/

Regardless of his expertise or lack of it, what I find most fascinating about Guy is that the format of his spiel is similar to that of any number of self-proclaimed authorities in alternate archaeology, physics, psychology and spiritualism -- the pop gurus of Atlantis, cold fusion, New Age healing and paranormal investigations. The four giveaways are the glib use (often misuse) of technical terminology to create an air of authenticity, the bashing of establishment thought to project a character of truth-seeking and altruism (often with an implication of selfless martyrdom), the lack of established credentials and/or presence of questionable credentials, and always the push to self-publicize.

« Last Edit: June 23, 2013, 10:27:25 pm by daws »
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texshooter

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Re: PK Sharpener Question
« Reply #27 on: June 23, 2013, 10:34:00 pm »

Regardless of his expertise or lack of it, what I find most fascinating about Guy is that the format of his spiel is similar to that of any number of self-proclaimed authorities in alternate archaeology, physics, psychology and spiritualism -- the pop gurus of Atlantis, cold fusion, New Age healing and paranormal investigations. The four giveaways are the glib use (often misuse) of technical terminology to create an air of authenticity, the bashing of establishment thought to project a character of truth-seeking and altruism (often with an implication of selfless martyrdom), the lack of established credentials and/or presence of questionable credentials, and always the push to self-publicize.


It's called salesmanship.
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Schewe

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Re: PK Sharpener Question
« Reply #28 on: June 24, 2013, 12:20:37 am »

It's called salesmanship.

So, salesmanship includes lying? Salesmanship includes denigrating competing products? I suppose it does if you are a used car salesman (or a snake oil salesman).
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Garnick

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Re: PK Sharpener Question
« Reply #29 on: June 24, 2013, 10:32:23 am »

I'll be the first to admit that I'm certainly no expert on this subject as it pertains to the "Guy Gowan Show".  Most of my business is built around printing for local photographers, as well as fine art reproductions.  I rarely use ACR except to recover some image data in a particularly ornery file I've been presented with.  Due to the fact that one of my major customers(also a long time friend) is a devotee of Guy, I was finally inspired to watch one of his videos mentioned on a recent post in this thread.  I'm a big fan of Jeff's work and dedication to this industry, as well as his contributions to this forum and the videos he and Michael have produced.  It's been rather enlightening to read his replies here as usual.

Now back to my lack of expertise in ACR.  My aforementioned customer/friend was telling me about yet another "amazing" revelation he had found in one of Guy's recent vids.  Having waded through the Focus 02 video I am now trying to make my way through Focus 01.  I have just reached the part where he is talking about the shadow recovery function of ACR, LR etc and the house across the street that he shot a few minutes before recording that video.  I noticed that in ACR he had stepped back from 2013 to 2010 version in order to show the difference between the two versions when indicating the amount of highlight clipping.  My customer/friend was telling me a few days that Guy had recommended never using the 2013 version of ACR for that particular function because it isn't as accurate as 2010.  I thought I would throw this out to the folks here who are much more involved with the "science" of ACR than I am.  What are your thoughts on this function of ACR(clipping indicators) in v2013 as opposed to v2010?  I'd like to be able to put together a somewhat educated reply to my customer when he asks my opinion of Guy and his approach to ALL things digital, and the fact that his is the ONLY valid method on Planet Earth.  I guess I've tipped my hand here somewhat, but people who come on as the latest and greatest in that manner don't last long in my world.  When the only way of projecting one's so called expertise is to first slam every other possible method, and then pick little goodies from other sources that have been in existence for many years and pretend they were your own brainchild, not my cuppa.  

Gary                  
« Last Edit: June 24, 2013, 11:40:59 am by Garnick »
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digitaldog

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Re: PK Sharpener Question
« Reply #30 on: June 24, 2013, 11:42:41 am »

My customer/friend was telling me a few days that Guy had recommended never using the 2013 version of ACR for that particular function because it isn't as accurate as 2010.

Accurate? That's an easy buzzword to throw out but it's kind of meaningless without a through description of what is meant with some metric of inaccuracy (like the differences between a reference value and the output values is a dE of 1.3). So when someone says this is more or less accurate, without backing up the methodology used to come up with the conclusions, the hair's on the back of your neck, like mine should raise!
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Garnick

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Re: PK Sharpener Question
« Reply #31 on: June 24, 2013, 12:05:21 pm »

Accurate? That's an easy buzzword to throw out but it's kind of meaningless without a through description of what is meant with some metric of inaccuracy (like the differences between a reference value and the output values is a dE of 1.3). So when someone says this is more or less accurate, without backing up the methodology used to come up with the conclusions, the hair's on the back of your neck, like mine should raise!

Thanks for that Andrew.  I assume you haven't seen the video I was referring to from the "Guy".  He has on screen a wedding shot wherein the brides white dress is of course lacking a lot of detail in order to maintain shadow detail throughout the rest of the image.  He then shows that although all of his clipping parameters are turned on there is no indication of any clipping in the highlights.  At that point he reverts back to v2010 in the "Process" tab and it shows a rather large amount of highlight clipping, which he proceeds to overcome with the "Exposure" slider.  It does seem rather evident that v2010 is for some reason indicating clipping where v2013 is not.  I'm not at all sure why that would be the case, so if you could provide an answer to that it would be much appreciated.  For me it's not so much a matter of metrics as perhaps a possible indication that v2013 is not indicating highlight clipping with the same degree of "accuracy" as was the case with v2010.  I'm not sure I am making any sense here at all, even though it somehow seems reasonable to me that v2013 may not be telling the whole truth as far as clipping is concerned.  Any further light you can shed on this would certainly be helpful.

Thanks again,
Gary   
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bjanes

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Re: PK Sharpener Question
« Reply #32 on: June 24, 2013, 12:07:16 pm »

Accurate? That's an easy buzzword to throw out but it's kind of meaningless without a through description of what is meant with some metric of inaccuracy (like the differences between a reference value and the output values is a dE of 1.3). So when someone says this is more or less accurate, without backing up the methodology used to come up with the conclusions, the hair's on the back of your neck, like mine should raise!

Accuracy can not be defined without knowing a reference value for comparison. This guy might be using departure from scene referred values as an indication of inaccuracy. With PV 2010 one could obtain scene referred values by setting the sliders on the main ACR tab to zero and setting the point curve to linear. Obtaining scene referred values with PV 2013 is not straight forward since this version uses image adaptive algorithms that protect highlights. However, for rendering into an output space, one does not want linearity and the PV2013 controls give superior results with less work.

Bill
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digitaldog

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Re: PK Sharpener Question
« Reply #33 on: June 24, 2013, 12:13:11 pm »

He has on screen a wedding shot wherein the brides white dress is of course lacking a lot of detail in order to maintain shadow detail throughout the rest of the image.  He then shows that although all of his clipping parameters are turned on there is no indication of any clipping in the highlights.  At that point he reverts back to v2010 in the "Process" tab and it shows a rather large amount of highlight clipping, which he proceeds to overcome with the "Exposure" slider.  It does seem rather evident that v2010 is for some reason indicating clipping where v2013 is not.

I still don't feel that's got anything to do with accuracy. There's a difference yes. The raw data is the same of course. The rendering controls between versions isn't. Neither can be said to be accurate or inaccurate IMHO. The correct statement would be "they are different". If you have a bias, you can attempt to prejudice others by suggesting one isn't accurate but again, that's not useful. There isn't clipping in the truest sense if the rendering controls bring back the data unclipped!
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jrsforums

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Re: PK Sharpener Question
« Reply #34 on: June 24, 2013, 12:48:28 pm »

Thanks for that Andrew.  I assume you haven't seen the video I was referring to from the "Guy".  He has on screen a wedding shot wherein the brides white dress is of course lacking a lot of detail in order to maintain shadow detail throughout the rest of the image.  He then shows that although all of his clipping parameters are turned on there is no indication of any clipping in the highlights.  At that point he reverts back to v2010 in the "Process" tab and it shows a rather large amount of highlight clipping, which he proceeds to overcome with the "Exposure" slider.  It does seem rather evident that v2010 is for some reason indicating clipping where v2013 is not.  I'm not at all sure why that would be the case, so if you could provide an answer to that it would be much appreciated.  For me it's not so much a matter of metrics as perhaps a possible indication that v2013 is not indicating highlight clipping with the same degree of "accuracy" as was the case with v2010.  I'm not sure I am making any sense here at all, even though it somehow seems reasonable to me that v2013 may not be telling the whole truth as far as clipping is concerned.  Any further light you can shed on this would certainly be helpful.

Thanks again,
Gary   

In my limited, possibly slightly unscientific, testing, I seemed to see that PV2010 showed clipping about when only one channel was clipped.  Recovery would allow some of that to be pulled back (recovered), with differing degrees of success and texture.

2013, irrespective of what Jeff stated, does seem to apply a level of automatic recovery.  I am not sure at what level it stops nor how it determines the stop point.  Measurements in RawDigger indicate that one channel will clip at ~97%....between 97% and 100% (full clipping) can be more that 2 stops.  In that range, color accuracy and texture will diminish dependent on the amount of clipping/recovery success.  Best practice is not to clip any RAW channels.
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bjanes

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Re: PK Sharpener Question
« Reply #35 on: June 24, 2013, 12:55:01 pm »


Neither can be said to be accurate or inaccurate IMHO. The correct statement would be "they are different". If you have a bias, you can attempt to prejudice others by suggesting one isn't accurate but again, that's not useful. There isn't clipping in the truest sense if the rendering controls bring back the data unclipped!

The raw data is either clipped or not. Highlight recovery does work within limits, but that does not mean the raw file was not clipped. The best tool to check for clipping is probably Rawdigger. PV2012 is not good for this purpose because of its image adaptive algorithms that protect the highlights. With ACR me own experiments indicate it is best to use PV2010 with a linear tone curve and take the baseline offset into account.

Bill
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Schewe

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Re: PK Sharpener Question
« Reply #36 on: June 24, 2013, 01:01:26 pm »

At that point he reverts back to v2010 in the "Process" tab and it shows a rather large amount of highlight clipping, which he proceeds to overcome with the "Exposure" slider.  It does seem rather evident that v2010 is for some reason indicating clipping where v2013 is not.  I'm not at all sure why that would be the case, so if you could provide an answer to that it would be much appreciated.  For me it's not so much a matter of metrics as perhaps a possible indication that v2013 is not indicating highlight clipping with the same degree of "accuracy" as was the case with v2010.

PV 2012 (not 13 yet) takes an entirely different approach to tone mapping than PV 2013/2010. Where in PV 2010 the processing couldn't extract image texture in 2012 it can. So, yes, in PV 2010 the data was clipped in 2012 it isn't. PV 2012 was brought about due to research from 3 pretty bright guys (including Jan Kautz from University College of London, the other two guys are from MIT). You can read about the research in this article Magic or Local Laplacian Filters?. Note, it's pretty deep stuff...

The bottom line is that Guy is a Photoshop "expert" so it's in his best interest to tout his Photoshop skills and his actions. It's not in his best interests to learn to use and then teach how to do what he does in Camera Raw. You notice he always pulls Exposure down in ACR or Aperture then "fixes" the resulting dark image in Photoshop? Well, his before and after results are skewed because he's intentionally making the image look bad before coming along and fixing it in Photoshop. Why not just adjust the image in ACR? Because then he couldn't sell you his actions...

In all of his example images, he left image quality on the table by ignoring image optimization until opening the image in Photoshop. He denigrates Camera Raw as a way of inducing his viewers to ignore the functionality and capabilities of Camera Raw. Yes, when you pull Exposure 1.5+ stops, you are gonna need some heavy duty fixing in Photoshop. But that's the snake oil salesman doing that.

Up till tis recent go around I was will to consider Guy an eccentric...but no more. Not when he blatantly lied about the development of Lightroom and claimed Adobe copied Aperture. Nope...now I'm seeing him in a new light that is even more, uh, unfavorable.
« Last Edit: June 24, 2013, 01:03:30 pm by Schewe »
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Schewe

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Re: PK Sharpener Question
« Reply #37 on: June 24, 2013, 01:44:13 pm »

The raw data is either clipped or not.

Note that in Camera Raw, the clipping calculations are done in 8 bit based on the output color space set in Workflow Options. Also note there are 3 potential clipping indicators; holding down the option/alt keys when adjusting certain sliders, the on screen red for highlights and blue for shadows and the flashing triangle indicators on the histogram. Of the three perhaps the most accurate are the option/alt when moving a slider and the red/blue on screen indicator.

So, evaluating the differences between PV 2010 and 2012 in terms of clipping indicators being in 8 bit, it wouldn't surprise me that PV 2012 can (and does) get at more highlight texture detail that is not really clipped while PV 2010 shows the data as clipped.

When talking about "recovery", I think a lot of people get confused between recovery vs compression. PV 2012 does a lot of extreme highlight compression to mitigate clipping. Some people don't like that and you can work around that by using curves. When I think of recovery I think of the old Recovery algorithm in PV 2010. PV 2012 is NOT doing that sort of recovery...and PV 2012 doesn't suffer from the same color contamination that PV 2010 suffered from.

PV 2012 was originally designed for use in floating point HDR images...(see the Local Laplacian Filters article). It was adapted to work on non-HDR image in ACR/LR by the engineers and believe me, when I read the SIGGRAPH paper, my eyes rolled back in my head. I don't understand that stuff and never will.

But, I do know how to tell really smart people from not so smart people. I know Thomas and Eric pretty well and I've met Sylvain Paris (one of the authors of the paper) and they are really, really smart. I don't like the way Guy accuses Adobe of arrogance and denigrates the work of these guys...neither Thomas nor Eric are arrogant. OK, Mark Hamburg (the guy that started Lightroom and the second engineer to work on Photoshop) is a bit arrogant...but the engineers do this stuff to get the absolute best they can out of raw captures. They are not predisposed to back off on the raw processing and simply fix it in Photoshop.
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PhotoEcosse

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Re: PK Sharpener Question
« Reply #38 on: June 24, 2013, 02:35:49 pm »

Hmmmm......

Glad I brought that stuff over here to get a second opinion.

Very illuminating.

(Apologies for forgetting that Americans don't quite grasp the concept of "irony". I'll stick one of those wee yellow sticky notes on my monitor to remind me. :) )

.
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jrsforums

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Re: PK Sharpener Question
« Reply #39 on: June 24, 2013, 03:33:54 pm »

Note that in Camera Raw, the clipping calculations are done in 8 bit based on the output color space set in Workflow Options. Also note there are 3 potential clipping indicators; holding down the option/alt keys when adjusting certain sliders, the on screen red for highlights and blue for shadows and the flashing triangle indicators on the histogram. Of the three perhaps the most accurate are the option/alt when moving a slider and the red/blue on screen indicator.

So, evaluating the differences between PV 2010 and 2012 in terms of clipping indicators being in 8 bit, it wouldn't surprise me that PV 2012 can (and does) get at more highlight texture detail that is not really clipped while PV 2010 shows the data as clipped.

When talking about "recovery", I think a lot of people get confused between recovery vs compression. PV 2012 does a lot of extreme highlight compression to mitigate clipping. Some people don't like that and you can work around that by using curves. When I think of recovery I think of the old Recovery algorithm in PV 2010. PV 2012 is NOT doing that sort of recovery...and PV 2012 doesn't suffer from the same color contamination that PV 2010 suffered from.

PV 2012 was originally designed for use in floating point HDR images...(see the Local Laplacian Filters article). It was adapted to work on non-HDR image in ACR/LR by the engineers and believe me, when I read the SIGGRAPH paper, my eyes rolled back in my head. I don't understand that stuff and never will.

But, I do know how to tell really smart people from not so smart people. I know Thomas and Eric pretty well and I've met Sylvain Paris (one of the authors of the paper) and they are really, really smart. I don't like the way Guy accuses Adobe of arrogance and denigrates the work of these guys...neither Thomas nor Eric are arrogant. OK, Mark Hamburg (the guy that started Lightroom and the second engineer to work on Photoshop) is a bit arrogant...but the engineers do this stuff to get the absolute best they can out of raw captures. They are not predisposed to back off on the raw processing and simply fix it in Photoshop.

Jeff....I understand there is a lot of rolloff/compression at the highend in LR.

However, when you examine the RAW files for just about all files that have highlights above 97% in LR....at least one of the channels, often more, are clipped.

Whatever you want to call it, this is a level of autorecovery.  If it were not, the LR histogram would accurately reflect the clipping....or at least it should. 

You are big on saying people lie.  Why are you not attacking this lie?  It is at least a "white lie"....protecting people from using poor shooting technique/errors.  BTW...I like it and understand why it was put in....but would really like a true RAW histogram, so I didn't have to go off to RawDigger.

BTW...I think it is time to let up on Guy.  I don't like his "schtick" either, but getting his facts wrong does not necessarily make him a lier.  There have been lots of stories about LR development, including one where Adobe did, or was about to, kill it until they heard about Aperture.  I suspect there is more than one "true" story...depending on who you talk to and what they remember.
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