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Author Topic: PSD with embedded color profile cross OS issues  (Read 7641 times)
digitaldog
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« Reply #20 on: September 03, 2010, 08:56:47 AM »
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Are you saying that every image and every scan you deal with is "correct" to start with?

My job as a scan operator (something I did professionally for years) is to either match as closely as possible, the original or improve it. The later happens globally with good scanning software at the scan stage not afterwards in Photoshop. The reason is the same as I stated; its faster and provides far better quality data.

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Camera Raw's "default" is only an arbitrary starting point. There's nothing sacred, nothing neither technically accurate nor particularly important with the default rendering of your capture. It's only a consistent place from which to start your evaluation and, ultimately your editing.

You are either misunderstanding the writing here or using the text to imply that what Dan suggests makes any sense at all. Do you have any idea how butt awful nearly all images appear with the controls set to zero? Are you sure you are reading the above text to imply that making the image look awful using the supplied controls instead of providing a desired color appearance different from the defaults is what the authors are saying?

You need to read that book again, because in no way are the authors (both partners of mine) implying what Dan is saying to his minions is necessary nor why he proposes this nonsense (his idea about the “master” curve, another made up term**). They are not advocating anyone set the various controls at the settings other than that which produce a desired appearance IN ACR.

** I suggest you read this http://www.luminous-landscape.com/essays/Curves.shtml
« Last Edit: September 03, 2010, 09:06:04 AM by digitaldog » Logged

Andrew Rodney
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« Reply #21 on: September 03, 2010, 09:01:05 AM »
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My understanding of this is if someone inadvertently takes an image that has been underexposed by a couple of stops then re assigning the gamma will be a better starting point for editing an image.

Your understanding isn’t correct. Get to the root of the problem. Either you have an image with an incorrect embedded profile and the color appearance looks poor as a result and you need to provide the correct description of the values OR you did a piss-poor job capturing the data and you need to begin with the correct values. Profiles as the name implies describe existing values or values that will exist after a conversion using it and the source profile that define those values. They are not designed nor intended for color correction. Why are your images (the existing RGB values) under exposed? That’s the questions you should be asking and attempting to fix!
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Andrew Rodney
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« Reply #22 on: September 03, 2010, 11:03:39 AM »
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You are either misunderstanding the writing here or using the text to imply that what Dan suggests makes any sense at all. Do you have any idea how butt awful nearly all images appear with the controls set to zero? Are you sure you are reading the above text to imply that making the image look awful using the supplied controls instead of providing a desired color appearance different from the defaults is what the authors are saying?

Unquote

I did state that I set everything to zero so I must see that they "are butt awful" ? They must be butt awful before Adobe sets an arbitrary setting to them? If I have a high contrast image imported to Camera raw then I don't want to start with an arbitrary setting that affects the image in a way that makes it even more high contrast. I want to start with a setting that is closer to the original. You seem to see everything in terms of a professional operator whilst most people try to see them from a photographic point of view? You also hector people when posting that is - imo - intended to bullying them into believing your theoretical point of view. You obviously know more about this subject than most but not from a practical point of view. I did state that the fixing of the photo was a favour and I recognized it was a poor image to start with but approached it in a practical manner rather than your theoretical scan operator ways which most people here aren't bothered about. To sum up a more practical approach rather than trying to browbeat people with profiles and RGB numbers would go down better?
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« Reply #23 on: September 03, 2010, 12:15:49 PM »
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I did state that I set everything to zero so I must see that they "are butt awful" ?

So when you set everything at zero, the raw images appear ideal to you? OR you alter the sliders to produce a desired color appearance? Dan’s stance is, you set everything to zero, render the data into Photoshop and now make the image look good. That’s just dumb for so many reasons.  

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They must be butt awful before Adobe sets an arbitrary setting to them? If I have a high contrast image imported to Camera raw then I don't want to start with an arbitrary setting that affects the image in a way that makes it even more high contrast. I want to start with a setting that is closer to the original.

Zero setting isn’t the original. The original is scene referred and ACR never produces that. A zero setting may attempt to get closer to a scene referred rendering but what’s the point of using a raw converter to render the data if you insist on setting everything to zero, then fixing the resulting mess in Photoshop? That’s exactly what Dan proposes. See: http://www.color.org/ICC_white_paper_20_Digital_photography_color_management_basics.pdf

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You also hector people when posting that is - imo - intended to bullying them into believing your theoretical point of view.

Not my intent and I think you are taking this too personally. Someone posted a very old link to Dan’s Color Theory list about using a bogus technique using ICC profiles. The link has salient points by myself and Chris Murphy as to why this is bogus. Find one color scientist, color software engineer, member of the ICC, author of a color management book or even an advanced user who agrees this is just a silly technique. Its akin to having an image that is too dark on screen and “fixing” the issue by upping the backlight of the display to make it brighter. Well heck, the image doesn’t look dark anymore, issue fixed. That the numbers didn’t change didn’t occur to the person who thinks this made an improvement (as the numbers in the original image didn’t change with the new profile assignment). That the image is still dark and subsequent images will likely be captured too dark due to some error in operation isn’t on these people’s radar and it should be. A “false profile” fixed the issue. Well it didn’t.

Zeroing ACR sliders, rendering and then making the image appear as you desire later in Photoshop is equally silly. Think about it before you suggest that I’m bullying but rather asking you to use that organ between your ears. Instead of taking what Dan or I say as gospel, why not think about the practical implications here and do some testing.

And here lies the issue I have with Dan. He has designed controversial ideas and techniques that have very little peer review, or I should say, he never answers the peer review provided but instead hides behind his Color Theory Yahoo list which is heavily moderated and censored. Chris and I, among others were banned from posting because peer review isn’t on Dan’s mind and apparently those who read his list. There is a link to Mark’s article on Curves as a counter to Dan’s ideas and while Dan was invited to further discuss this, he never did. I wonder why? There are his flat earth theories about 16-bit editing that was addressed in a peer review by a very smart color scientist named Bruce Lindbloom (see: http://www.brucelindbloom.com/index.html?DanMargulis.html). Any reply to this peer review? Nope. In fact, outside his censored list, can you find any posts by Dan on any site where his ideas are questioned? Nope. The issue is, poor end users like yourself read this stuff and believe that setting ACR sliders to zero or using a false profile, or believing that high bit editing is unnecessary just take it like its a fact. Despite the facts that scanner and camera, display and some printer manufacturers support high bit workflows and have for years. The color scientists there are wrong and Dan’s right? Thomas Knoll who designed Photoshop is wrong about how he coded the curves and other sliders in ACR but Dan’s right?

Find an Adobe engineer, a color scientist, author or expert on color management who agrees with the three flat earth theories uncovered above.

Try this. Alter the sliders to your hearts content in ACR to produce a rendering you like and hit OK. Then do the same task with the sliders set to zero and fix the mess in Photoshop. Which took longer overall? Really look at the data, which is cleaner? Now consider you have to do this to 20 images let alone 200. Don’t use a “false profile”, just crank up the display luminance and would you agree the image looks better?

I think I own every book Dan’s written. I’ve seen him present a number of times at Photoshop world. We’ve even broken bread on occasions (in some cases I’ve seen bread thrown at him but that’s another story). He has some very useful information to provide, along with some severely silly ideas about image processing. The problem is, people read both and without testing the waters, or looking for true peer review, or asking others if the idea makes sense, they go off and believe its true and worse, post links to the dribble to others who are equally unable to decipher the good bits from the nonsense. If someone seriously questions these ideas to Dan, and the only place to do so is on his list, it doesn’t take long to get banned from the site. And the BS continues to float about the web which is a darn shame.
« Last Edit: September 03, 2010, 12:18:50 PM by digitaldog » Logged

Andrew Rodney
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« Reply #24 on: September 03, 2010, 04:02:22 PM »
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Certainly gamma 1.8 might produce the described result, but gamma is set when you create the display profile, not a setting you change. 
This isn't true.

http://www.ledet.com/margulis/ACT_postings/ProfilingandProofing/ACT-False-Profile.htm

I'm not quite sure how this relates to the disucssion.  The problem is someone viewing an image that is suspected of not having a "calibrated" display, and the possible answer is that person has the gamma set wrong on their mac, something related to the way macs default gamma used to be different than windows.

But there is no gamma "setting" on a Mac.  You can't go to the display preference pane and "change" the gamma.(I certainly don't have one).  The gamma is built into the profile, and certainly the person viewing this image, if indeed their display is "uncalibrated" indicates they don't have the knowledge of doing some strange task as discussed in the linked thread. And based on the mentioned embedded profile which is a display profile built by Apple, I seriously doubt it was built with gamma 1.8.


Actually, 1.8 was around after OSX was introduced, at least up until 10.4.  I think it changed after the move to Intel.  I have a G5 in my studio which shipped with 10.4 and it came from the factory set to 1.8.
If you build a profile with a gamma of 1.8 it doesn't look anything like the supplied apple profile, and hasn't for a long time.  An in fact it hasn't been used by those creating display profiles for even longer.  So while it might have been "around" and been the "default", no one building display profiles including apple has used it for a long time.  (Of course, "long" is a relative term when speaking of computer technology).
« Last Edit: September 03, 2010, 04:11:39 PM by Wayne Fox » Logged

gromit
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« Reply #25 on: September 03, 2010, 09:08:27 PM »
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The questions you should be asking yourself is what is assigning the profile doing, why is the image blocked up in the first place.

Since your real world experience would appear to be somewhat limited, let me pass on the following:

A few days ago I printed a chiaroscuro image for a client. We were looking at the resultant print and she was telling me how important the detail in deep shadows in the foreground was and how she had recently bought a new monitor, carefully calibrated it (presumably to gamma 2.2) and tuned the shadows precisely. However, when I had opened the image on my monitor (hardware calibrated to L*) I could see the shadows were blocked. I precisely linearize all B&W output so printing it as is would result in these blocked shadows and kill the image. My role, as I see it, is to second guess what the client wants and deliver this. So I applied an Adobe RGB (1998) profile modified with an sRGB gamma curve and its linear toe opened up the shadows to what she intended, even if the file she supplied didn't convey this. It's a simple enough trick.

Now you can argue all you like about how "false profile" isn't a valid name and how this is counter to all colour-management principles (blah blah blah) but the fact is it delivered the results ... and has done on many, many occasions. In fact, pretty well every gamma 2.2 based file I receive with important shadow detail needs such treatment. Maybe you should give it a try. Or you could print the image as is, tell them that the blocked shadows are all their fault, they should know better than to use gamma 2.2 etc. Guess which one of us will have more repeat clients.
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« Reply #26 on: September 04, 2010, 03:03:02 AM »
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Zeroing ACR sliders, rendering and then making the image appear as you desire later in Photoshop is equally silly.

Unquote

That isn't what I do. I zero the sliders and then render the image in ACR first just as anyone does and then import to Photoshop. In your original post you didn't make clear that Dan was zeroing the sliders and importing the image directly to Photoshop hence the reason for defending the use of the zeroing method. I think in your haste to badmouth him you don't always do it in a "objective" manner but you give him both barrels without giving any leeway. This doesn't go down well with a lot of people. Like him or loath him he has sold a lot of books and I see him as a pioneer who doesn't always get it right? The fact that you and others attack him means that a lot of people learn from it. I just wish your attacks would be a bit better balanced and we could learn more?
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« Reply #27 on: September 04, 2010, 03:07:35 AM »
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This isn't true.

http://www.ledet.com/margulis/ACT_postings/ProfilingandProofing/ACT-False-Profile.htm


I'm not quite sure how this relates to the disucssion. 

Unquote

I was just pointing out that gamma could be changed. It wasn't a dig at you, but trying to add to the post. Unfortunately a bull in the China shop proceeded on a trampling operation bellowing bellicose that wasn't needed.
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jbrembat
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« Reply #28 on: September 04, 2010, 03:38:31 AM »
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So I applied an Adobe RGB (1998) profile modified with an sRGB gamma curve and its linear toe opened up the shadows to what she intended, even if the file she supplied didn't convey this. It's a simple enough trick.
There are other methods to open shadows editing the image not the profile.

If you start to change profiles instead of RGB numbers, you are on the wrong way.
You can think that the results are about the same, but it isn't true.

Suppose you are preparing a photo for web publishing.
You can correct the lut of sRGB color space to make the image brighter.
But your change is in the profile, RGB numbers are the same.
On non color managed browser your editing does not exist.

Jacopo
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gromit
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« Reply #29 on: September 04, 2010, 03:41:15 AM »
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There are other methods to open shadows editing the image not the profile.

If you start to change profiles instead of RGB numbers, you are on the wrong way.

OK, I'm game. Why?
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« Reply #30 on: September 04, 2010, 03:42:02 AM »
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Zero setting isn’t the original. The original is scene referred and ACR never produces that. A zero setting may attempt to get closer to a scene referred rendering but what’s the point of using a raw converter to render the data if you insist on setting everything to zero, then fixing the resulting mess in Photoshop? That’s exactly what Dan proposes. See: http://www.color.org/ICC_white_paper_20_Digital_photography_color_management_basics.pdf

Unquote
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That’s why he suggest silliness like setting ACR controls all to zero, then ‘fixing’ the resulting turd in Photoshop with a lame excuse that the curves in ACR are broken (despite the fact that it was designed this way from some very smart people at Adobe). If all you know is a hammer, everything looks like a long, extended Photoshop exercise to fix the sloppiness at capture.

Unquote

Andrew please educate me if possible. I have read the link four or five times and I don't see a reference to zeroing sliders and importing directly to Photoshop. What I read is about the difficulties of getting data from Raw to Photoshop that is rendered the same. He writes about different converters doing it differently with different colour spaces. It is well known that different companies keep their secrets well guarded thus it is impossible to get the same result with different converters. You are obviously are clued up better than most, but I can't see where you draw this conclusion? You are deducing more than I can.
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« Reply #31 on: September 04, 2010, 10:23:35 AM »
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Andrew please educate me if possible. I have read the link four or five times and I don't see a reference to zeroing sliders and importing directly to Photoshop.

Just check the Color Theory archives, the only place you’ll find actual text by Dan, a often difficult cookie trail by design. Note “this new workflow” is some “fix the turd in Photoshop” that you broke by zeroing out all the sliders.

Here’s one such post by Dan:

On Apr 18, 2008, at 2:32 PM, Dan Margulis wrote:

With respect to doing things that might make the picture temporarily look
better, ACR should be avoided in this workflow because of its master-curve
approach to setting range. Instead, accept the camera's white balance and
zero everything else out
. I recommend this approach even in traditional
workflows, but in this new workflow it's particularly necessary.

------

In a reply post to Jerry asking about this strange idea the same day:

> Second, what is the meaning of zeroing everything out in ACR? My
> hypothesis is this:
>
> Start by setting the default ACR settings (below the white-balance
> settings), which includes these zeros: Exposure, Recovery, Fill
> Light, Clarity, Vibrance, and Saturation. Then, change the setting
> for Blacks from 5 to 0 (to leave the shadow point lighter). I think
> Brightness should probably be left at its default of +50.

It should not. this is an example of the sort of setting referred to earlier, one
that makes the image look better temporarily but in the long run is damaging.

The inadequacies of ACR's implementation of this command have been
discussed at some length in the thread and are also mentioned in Stephen
Marsh's post that hit the list at approximately the same time as yours.

> For me the main quandary is what to do with Contrast. Leave it at the
> default of +25?

No. Also, the curve setting should be set to Linear. Each of these defaults
suppress shadow and highlight detail in the interest of enhancing the
midrange of each channel. While that sacrifice may well be what we want to
do at some later time, in the context of this workflow it's premature to make the
decision in the raw module
. We have plenty of time to do it later on, if that's
what we want.
-------

And Dan’s take on ACR and perhaps raw rendering in general (hard to know if he’s ever use any other raw converter):

On Apr 28, 2008, at 10:27 PM, Dan Margulis wrote:
Additionally, some of the bells and whistles found in raw modules emulate
expert-only tools in Photoshop. Not as flexible, but still opening the door to the
less skilled.

I tested ACR carefully in Photoshop CS2, not from the point of view of the
beginner but the skilled user. I was not really concerned with how much time
was involved. I can see white balance as a useful, possibly time-saving
alternative to correcting certain casts in Photoshop, but it does not offer
superiority. The remainder of ACR/CS2 is seriously impacted by the
inadequate range-setting routines*. Consequently, I wrote that I was unable to
find any images where a better final result could be obtained by any
combination of ACR/CS2 commands than by opening with everything zeroed
out.


So the silly idea is two fold. One, there’s something wrong with ACR of which Mark addressed in his piece on curves referenced already. A peer review again ignored by Dan. 2nd, the idea you should build a turd in ACR because of this silly idea and then fix it in Photoshop. Note he’s referring to ACR in Photoshop CS2, I have seen nothing from Dan since then that states otherwise begging the question if Dan has looked at updates to the ACR engine since then. I suspect not.

*Another made up Dan term that needed clarification on the list (people asking, WTF are you referring to). But that’s a different story.
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« Reply #32 on: September 04, 2010, 10:39:03 AM »
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A few days ago I printed a chiaroscuro image for a client. We were looking at the resultant print and she was telling me how important the detail in deep shadows in the foreground was and how she had recently bought a new monitor, carefully calibrated it (presumably to gamma 2.2) and tuned the shadows precisely. However, when I had opened the image on my monitor (hardware calibrated to L*) I could see the shadows were blocked.

Why and how do you ensure this doesn’t happen again? This was from a scan? Raw capture with less than idea rendering? The damage is done so to speak. The shadows are blocked. Assigning a profile doesn’t change that fact.
You continue to ignore the facts that: A. The image had blocked up data and B, the “false profile” didn’t change that one bit (the numbers did not change). You could have cranked up the display luminance to make the image appear brighter and maybe seen the shadows more easily but this “fix” is no different from what you did with this so called false profile. The numbers are exactly the same as they were from the get go. Do you not see this correlation?

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Now you can argue all you like about how "false profile" isn't a valid name and how this is counter to all colour-management principles (blah blah blah) but the fact is it delivered the results ... and has done on many, many occasions. In fact, pretty well every gamma 2.2 based file I receive with important shadow detail needs such treatment. Maybe you should give it a try. Or you could print the image as is, tell them that the blocked shadows are all their fault, they should know better than to use gamma 2.2 etc. Guess which one of us will have more repeat clients.

Again, you are missing what’s happening here. I’ll try once more. The values didn’t change. The description of the values did. When you converted to whatever output color space you used to print, this new definition was used as the source of the conversion. Had you pulled a curve or used some other more controllable function in Photoshop to change the numbers, you’d have ended up with different values prior to the conversion. The false profile and the original profile both produce different RGB values after a conversion. This magic false profile, in the case of a 2.2 gamma adjustment (or vise versa) is a very simple curve, nothing more, that is applied to the data when you convert. You had less control using this simple, preset curve (from the gamma adjustment) than had you just pulled a curve on an adjustment layer and worse, unlike an adjustment layer, you have no further control over a layer, its not non destructive in terms of the adjustment layer prior to flattening and printing. You pulled a simple and uneditable curve using the wrong (or one should suggest correct) profile assignment in the crudest fashion when you could have used the Photoshop tool set correctly, with more control and with more options. You basically moved to the “beginner” mistake of correcting tone using the old Contrast and Brightness slider rather than using the advanced and more controllable Curves on an Adjustment layer. Feel better about this silly “false profile” now?

What you need to do is sit down and contemplate what the assignment of an ICC profile does to an image when you use Assign Profile and after. Then contemplate what the goal of doing this is (why it was designed in the first place) and what you hope to accomplish in editing this image. You should see, as others besides myself have told you is, its a silly, not very effective use of the wrong tools found in Photoshop. A technique that can be done with far more control and options today and into the future editing of the document. You are using that funny looking knife used to clean a dirty horse hoof as a scalpel for delicate brain surgery which those of us who understand these things are telling you is not a good use of the toolset.
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« Reply #33 on: September 04, 2010, 10:56:51 AM »
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That isn't what I do. I zero the sliders and then render the image in ACR first just as anyone does and then import to Photoshop.

Good. I still see no reason to start with zero settings that would make most images look far worse than a default rendering you can build (you can create you own ACR defaults) but the bigger issue is you are NOT doing what Dan suggests. Zeroing out the sliders and using that as a rendering for all other work in Photoshop.


Quote
In your original post you didn't make clear that Dan was zeroing the sliders and importing the image directly to Photoshop hence the reason for defending the use of the zeroing method.

And your post, in reference to Dan’s ACR ideas didn’t make it clear you zero out the sliders as a starting point then make the image look good using those sliders (notice I did ask you about this). Hopefully you can see that zeroing out the sliders and hitting Open in ACR is a flat earth theory of an idea.

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I think in your haste to badmouth him you don't always do it in a "objective" manner but you give him both barrels without giving any leeway. This doesn't go down well with a lot of people. Like him or loath him he has sold a lot of books and I see him as a pioneer who doesn't always get it right? The fact that you and others attack him means that a lot of people learn from it. I just wish your attacks would be a bit better balanced and we could learn more?

Dan’s a big boy and can defend his ideas outside his list if he wishes but he doesn’t dare do so thanks in large part to what happened in the early 90s when he did this on the old Compuserve Photo forum and Bruce Fraser (among others) tore him a new one on many occasions. That’s how far back Bruce and I (and Dan) go in terms of peer review of Dan’s ideas. I have some of this also archived, its hilarious how Bruce would chop Dan’s legs off as only Bruce could. God I miss him. But to get back to your point above, I don’t feel I’m bad mouthing him, I’ve got plenty of original text as seen here that allows his ideas to speak for themselves even if he will not outside his highly censored list. Its too bad I have to archive and present them outside the list. I’ve seen scores of end users drink this koolaid for years and I feel for them. Its not about getting it right or not. There is simply no peer review process here and one can only imagine how many unsuspecting readers think that the ACR zero idea, the misunderstanding of high bit editing or other such strange ideas are not worth questioning.
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« Reply #34 on: September 04, 2010, 11:31:52 AM »
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You basically moved to the “beginner” mistake of correcting tone using the old Contrast and Brightness slider rather than using the advanced and more controllable Curves on an Adjustment layer.

We're talking about a micro adjustment here and Curves just don't do the same job. This was explained on the linked thread. Often a fixed tweak to the deepest shadows with the method outlined is just what's needed.

I honestly question whether you simply don't understand things outside of your limited world (you certainly show no evidence of trying them out in a practical sense) or your increasingly long-winded and belittling responses are just arguing for arguing sake.
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« Reply #35 on: September 04, 2010, 11:44:54 AM »
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They work for me, probably because I spent the time investigating how they could be used effectively in my own workflow rather than endlessly arguing on internet forums that they don't.
We're talking about a micro adjustment here and Curves just don't do the same job.

With all due respect, that’s nonsense. The investigation is sloppy and incomplete! Look at the very simple curves used in the profiles, there is a single point curve in the 1.8, a tiny tweak in the 2.2, both or which are easily achieved using PS’s curves and then some. That more complex and more customizable curves can be produced in Photoshop and applied as an adjustment layer seems to have escaped you. Do you even understand what a gamma curve is? In the case of sRGB, its not a true gamma curve because of that tiny extra point in the curve in the shadows, a curve a beginning Photoshop user could produce. Again, you need to investigate this far more before posting. ICC profile curves in an RGB working space are very simple and very easy to produce with virtually no options (you can only specify a value); have you ever even done this? And it doesn’t change the fact you using the wrong tool for the wrong job; the profiles were never intended for the purpose you are using them for as explained ad nauseam already.
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« Reply #36 on: September 04, 2010, 12:12:11 PM »
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Now you can argue all you like about how "false profile" isn't a valid name and how this is counter to all colour-management principles (blah blah blah) but the fact is it delivered the results ... and has done on many, many occasions. In fact, pretty well every gamma 2.2 based file I receive with important shadow detail needs such treatment. Maybe you should give it a try. Or you could print the image as is, tell them that the blocked shadows are all their fault, they should know better than to use gamma 2.2 etc. Guess which one of us will have more repeat clients.

Setting aside all the colour management principles which Andrew has described very well here, I would just focus on this question of how to reveal shadow detail. Firstly of course the detail needs to be retrievable from the image data. As long as it is, there are far superior tools in Lightroom and Photoshop for doing this in a highly controlled and non-destructive manner. I'll just provide some examples - in Lightroom, the combination of Fill and Blacks is capable of opening shadow detail while restoring DMax and needed contrast in the shadow regions of the image. If that isn't good enough, the area can be masked in Lightroom and the exposure, brightness, contrast of the masked area increased. Once the image is sent to Photoshop, there are yet other ways of bringing out shadow detail so powerfully that they need to be carefully controlled - for example, masking the area needing attention into a Curves adjustment layer and changing the blend mode to Color Dodge or Screen, then adjusting the shape of the Curve and the layer opacity to fine-tune the result. Techniques such as these are far superior to fiddling with profiles because they are (a) non-destructive, (b) editable after the fact, and (c) capable of far more precision.

I'll just add a footnote about zeroing sliders in Camera Raw and Lightroom. My default settings in those programs are exactly that, with the Tone Curve set to linear. But this is just to provide myself with a starting point which features "no adjustments" in terms of the program's controls. It's useful, because contrastier starting points CAN indeed block shadows and clip highlights making you believe these are image problems rather than program settings problems. Then I build the image from there within LR or ACR, using those tools to the maximum effectiveness I can derive from them. Only then do I send the image to Photoshop. This is largely a matter of taste - other people may prefer to start their editing on the basis of one of Adobe's image defaults which provide more contrast and brightness from the get-go. The point is - wherever you start from it is best to then use these tools to their maximum effectiveness relative to your image requirements within these raw converters before rendering the image to Photoshop.
« Last Edit: September 04, 2010, 01:55:10 PM by Mark D Segal » Logged

Mark D Segal (formerly MarkDS)
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Wayne Fox
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« Reply #37 on: September 04, 2010, 12:53:56 PM »
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Unfortunately a bull in the China shop proceeded on a trampling operation bellowing bellicose that wasn't needed.
Such is the internet.

As an aside to your bull in a china shop reference ( a saying I myself use frequently), amazingly enough as demonstrated by the Mythbusters on Discovery Channel, this may indeed be a myth as they successfully put several bulls in a "china shop" without any major damage to the china .  I was quite amazed personally. The beasts are amazingly nimble.
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stamper
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« Reply #38 on: September 05, 2010, 03:17:21 AM »
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Quote

I'll just add a footnote about zeroing sliders in Camera Raw and Lightroom. My default settings in those programs are exactly that, with the Tone Curve set to linear. But this is just to provide myself with a starting point which features "no adjustments" in terms of the program's controls. It's useful, because contrastier starting points CAN indeed block shadows and clip highlights making you believe these are image problems rather than program settings problems. Then I build the image from there within LR or ACR, using those tools to the maximum effectiveness I can derive from them. Only then do I send the image to Photoshop. This is largely a matter of taste - other people may prefer to start their editing on the basis of one of Adobe's image defaults which provide more contrast and brightness from the get-go. The point is - wherever you start from it is best to then use these tools to their maximum effectiveness relative to your image requirements within these raw converters before rendering the image to Photoshop.

Unquote

My thoughts exactly thus the quote from the Camera raw CS2 book. Ironically a few years ago we were getting good images out of Photoshop without first using a raw converter. A comparison of images from that bygone era with what we have now would be interesting. Sometimes I think Dan MIGHT have a point when he says that 8 bit and no raw conversion is all it takes? Do we sometimes get too hung up with using all the whistles and bells? If someone shows you a good image that was processed with the tools from ten years ago then how do you feel?
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Mark D Segal
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« Reply #39 on: September 05, 2010, 07:56:21 AM »
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My thoughts exactly thus the quote from the Camera raw CS2 book. Ironically a few years ago we were getting good images out of Photoshop without first using a raw converter. A comparison of images from that bygone era with what we have now would be interesting. Sometimes I think Dan MIGHT have a point when he says that 8 bit and no raw conversion is all it takes? Do we sometimes get too hung up with using all the whistles and bells? If someone shows you a good image that was processed with the tools from ten years ago then how do you feel?

I'm loathe to shadow-box with second-hand renditions of the thoughts of Dan, but of course I've heard this stuff too and if meant to be a general statement it's just rubbish. Converting a raw file is not an option, it's a necessity. The only issue is how you do the conversion - what you may be referring to as the "bells and whistles". An 8 bit conversion gives you 256 levels of luminosity and a 16 bit conversion gives you over 32,000 levels in the Photoshop implementation. The more levels in the data, the more leeway you have to perform very large image edits without loosing essential photographic quality. The wider the gamut, the more colors you will allow your printer to reproduce. This has all been tested and proven ad nauseum in theory and in practice by the best technologists and imaging professionals in the industry.

Now, you can avoid raw conversion altogether by shooting JPEGs from your camera. This is fine depending on the purpose of your photography. Remember, the JPEG format was developed for rapid, economically transmissible imaging at a time when bandwidth and speed weren't what they are today, but remains very useful today - particularly handy for photojournalists sending images from the field for immediate publication, posting images to websites, etc., and it's fine as far as it goes - in fact amazingly so - just last night I was processing some JPEGs my son-in-law shot of our grandchildren using his digi-cam; native resolution 240 PPI providing an image roughly 7*10 inches. At that size and with moderate editing in Lightroom (including some interesting conversions to sepia) they look great as family snapshots, which have a cherished place in our hearts. 

But as Andrew said repeatedly above - let's use the right tools for the job. If you want to make large prints of the highest photographic quality and have maximum editing flexibility on the way to your final result, you will be shooting raw, processing as much as possible in the raw converter (yes, using every bell and whistle they provide which the image needs) and rendering the image in 16-bit ProPhoto, if not printing directly from Lightroom (where you lose soft-proofing for now). That's just the way it is. You don't have to take my word for it, but the overwhelming conclusion of all the evidence out there is that these arguments with Dan were a waste of time and bandwidth when they happened, and they are even more so now. In fact I don't know where he stands on any of this these days and in any event it really doesn't matter. We know what we know based on our own experience and the contributions of the real technologists in this field.
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Mark D Segal (formerly MarkDS)
Author: "Scanning Workflows with SilverFast 8....." http://www.luminous-landscape.com/reviews/film/scanning_workflows_with_silverfast_8.shtml
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