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ICC false profiles for color grading/correction

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  #11  
Old 02-09-2017, 11:25 AM
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andrewrodney andrewrodney is offline
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Re: ICC false profiles for color grading/correctio

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Originally Posted by Tony W View Post
If you really want to play around with profiles you may want to investigate Adobe DNG profile editor (FOC), you can make some pretty accurate or wildly screwed profiles if that is what you want
Yes but only on raw data, within a converter that supports DNG camera profiles. But ACR/LR and a few other none Adobe converters indeed do so:

Everything you thought you wanted to know about DNG camera profiles:
All about In this 30 minute video, we’ll look into the creation and use of DNG camera profiles in three raw converters. The video covers:

What are DNG camera profiles, how do they differ from ICC camera profiles.
Misconceptions about DNG camera profiles.
Just when, and why do you need to build custom DNG camera profiles?
How to build custom DNG camera profiles using the X-rite Passport software.
The role of various illuminants on camera sensors and DNG camera profiles.
Dual Illuminant DNG camera profiles.
Examples of usage of DNG camera profiles in Lightroom, ACR, and Iridient Developer.

Low Rez (YouTube):
http://youtu.be/_fikTm8XIt4

High Rez (download):
http://www.digitaldog.net/files/DNG%...le%20video.mov
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  #12  
Old 02-09-2017, 02:30 PM
Shoku Shoku is offline
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Re: ICC false profiles for color grading/correctio

You can create altered profiles in Photoshop - see attached jpeg.

I have created Adobe RGB, and sRGB profiles with different Gammas (circled in the screen shot). It's quick and simple to assign these profiles to lighten or darken the image (only takes a few seconds, and because the only change is gamma the color is not adversely affected, as it could be with curves or some other adjustment tool).

The reason: we often receive images that do not display as they do to the client. This can be due to their monitors set to a different gamma. Assigning an altered profile is a quick way to check this, and often is the only "adjustment" necessary to achieve what the client expects.
Attached Images
File Type: jpg Screen Shot 2017-02-09 at 1.20.16 PM.jpg (235.9 KB, 9 views)

Last edited by Shoku; 02-09-2017 at 03:29 PM.
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  #13  
Old 02-09-2017, 02:55 PM
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andrewrodney andrewrodney is offline
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Re: ICC false profiles for color grading/correctio

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Originally Posted by Shoku View Post
You can create altered profiles in Photoshop - see attached jpeg.

I have created Adobe RGB, and sRGB profiles with different Gammas (circled in the screen shot). It's quick and simple to assign these profiles to lighten or darken the image (only takes a few seconds, and because the only change is gamma the color is not adversely affected, as it could be with curves or some other adjustment too).

The reason: we often receive images that do not display as they do to the client. This can be due to their monitors set to a different gamma. Assigning an altered profile is a quick way to check this, and often is the only "adjustment" necessary to achieve what the client expects.
You haven't achieved anything that can't be done faster using standard Photoshop tools like curves! The image, the RGB Values are either too dark, too light. Not because it's being previewed incorrectly. You might as well alter the display IF the image isn't actually too dark or light; the RGB values are indeed correct. Further, an edit will be applied upon a color space conversion. So either the RGB numbers need to be edited or they don't. The so called 'false profile' edits the numbers eventually because you need to convert the data. And outside an ICC aware application, it does absolutely nothing! Clients or otherwise that work with ICC aware applications and profiled display can use ANY GAMMA setting; it doesn't matter a lick! An image with an embedded ICC profile on a calibrated display with gamma 1.8 will appear the same on a display calibrated to Gamma 2.2 IN ICC AWARE APPLICATIONS. This is all pointless and invented by someone who didn't really understand what was going on here, under the hood.

So again: numbers are properly being previewed in an ICC aware app and too dark or light: Fix them; alter the values.
Numbers are not being properly previewed in an ICC aware app: the profile doesn't do squat at anytime.

There's no free lunch! Altering the display preview with an ICC Profile other than fixing the problem with the RGB numbers IF necessary isn't doing anything you couldn't do without that profile and, actually fix the problem if it exists: Alter the RGB numbers!
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  #14  
Old 02-09-2017, 03:09 PM
Shoku Shoku is offline
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Re: ICC false profiles for color grading/correctio

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Originally Posted by andrewrodney View Post
You haven't achieved anything that can't be done faster using standard Photoshop tools like curves! The image, the RGB Values are either too dark, too light. Not because it's being previewed incorrectly.
Altered profiles are a tool, like any other tool, and they work.

Why do they work? They work if the client is not seeing their image accurately to begin with, because their monitor is not calibrated properly (too light or too dark - it's usually too light). Assigning the same gamma they use fixes the appearance of the image (which is what "assigning" is meant to do - keep the numbers but change the appearance. Once the correct appearance is achieved, converting to the proper output profile, (in our case our CMYK press profile), preserves the appearance for printing.

Last edited by Shoku; 02-09-2017 at 03:30 PM.
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  #15  
Old 02-09-2017, 03:09 PM
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Re: ICC false profiles for color grading/correctio

Now where can altering an ICC Profile in Photoshop be somewhat useful for OLD digital cameras?
http://www.digitaldog.net/files/CameraProfilinginPS.pdf
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  #16  
Old 02-09-2017, 03:12 PM
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andrewrodney andrewrodney is offline
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Re: ICC false profiles for color grading/correctio

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Originally Posted by Shoku View Post
Altered profiles are a tool, like any other tool, and they work.

Why do they work? They work if the client is not seeing their image accurately to begin with, because their monitor is not calibrated properly (to light or too dark - it's usually too light). Assigning the same gamma they use fixes the appearance of the image (which is what "assigning" is meant to do - keep the numbers but change the appearance. Once the correct appearance is achieved, converting to the proper output profile, (in our case our CMYK press profile), preserves the appearance for printing.
They don't work, you and Photoshop are being lied to. Just as you can adjusting your display to make your images appear differently; pointless. And your idea about differing customer display gamma illustrates this is a solution in search of a problem. The answer is color management, a profiled display and viewing the RGB numbers correctly. You might as well go over to your clients location and muck around with the display controls outside an ICC aware app. (Which Photoshop clearly isn't). You're not fixing anything, your treating a gunshot wound with a tiny band-aid.
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  #17  
Old 02-09-2017, 03:26 PM
Shoku Shoku is offline
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Re: ICC false profiles for color grading/correctio

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Originally Posted by andrewrodney View Post
They don't work, you and Photoshop are being lied to. Just as you can adjusting your display to make your images appear differently; pointless. And your idea about differing customer display gamma illustrates this is a solution in search of a problem. The answer is color management, a profiled display and viewing the RGB numbers correctly. You might as well go over to your clients location and muck around with the display controls outside an ICC aware app. (Which Photoshop clearly isn't). You're not fixing anything, your treating a gunshot wound with a tiny band-aid.
Part of color management is the use of the assign function if necessary to reveal what the client intended on their end. This is true for untagged files as much as it is to determine proper density (gamma). Now, we don't use this tool for every image, but the ones we assign with altered profiles are usually in obvious need of a gamma adjustment. This assignment is not the final adjustment, just a quick way to get closer to what the client expects. It works if you know what you are doing and we've been doing this for decades, with perfect results - according to our clients.
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Old 02-09-2017, 04:32 PM
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Re: ICC false profiles for color grading/correctio

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Originally Posted by Shoku View Post
Part of color management is the use of the assign function if necessary to reveal what the client intended on their end. This is true for untagged files as much as it is to determine proper density (gamma).
Who gave you those silly ideas? They are both absolutely false, (like the profiles you are using); you were mislead by whoever taught you this falsehood.

I'll attempt to explain what the Assign Profile command is and why we may need it. It may fall on deaf ears but at least those lurking here who know just as little about color management as you (or less) will get factual information about this command.

Let's start here: R45/G250/B89 is a different color in sRGB than Adobe RGB (1998). They both share the same numbers! 1000 miles and 10000 kilometers are different distances but they too share the same numbers. RGB or CMYK numbers without a scale, and that is what the tagged/embedded ICC profile provides, are ambiguous. Just as asking me the distance between Santa Fe and Austin TX is ambiguous if I simply state 1000.

The Assign Profile command has one and only one fuction: To provide the CORRECT scale to the existing numbers. And we use it when we are provided untagged RGB or CMYK. Then the correct colors are represented to us based on the correct scale. They may need to be edited. And that's why Photoshop exists.

IF every image had an embedded profile, the Assign Profile command could disappear. And it has in many products where it is impossible to produce an untagged document. Like Lightroom (or ACR). It is impossible to produce an untagged image document from either and no Assign Profile command exists because it's totally unnecessary.

Untagged data can't be properly previewed in a color managed application unless that application makes the correct guess about the scale of the numbers. And that's where the PS Color Settings (working RGB/CMYK etc) come into play with respect to untagged data. Photoshop has to guess the scale of the numbers of untagged images and it uses what someone sets there.

If you open an untagged document that really is in sRGB and the color settings are set for ProPhoto RGB, the preview is wrong, a lie, ugly. And that's all you're doing with this silly false profile: assinging the wrong scale to exsting numbers. If we change the color settings in PS to sRGB, the untagged document previews correctly. But if we pass that onto anyone else, it's RGB mystery meat. So we ASSIGN, embed, sRGB into the document so the numbers have the correct scale. Now and into the future and when it is converted to any other color space (CMYK or otherwise).

You may say that you wish to drive from Austin to Santa Fe and do so in the shortest period of time while driving at 65 miles per hour. IF I lie to you and state the distance is 1000 kilometers instead of the correct scale, miles, what good did that do for you? You were lied to. And the time you think it will take for the drive is flawed. Just like your use of this silly 'false profile'. In a color managed applications, the numbers appear as they really are when the correct scale is associated with then numbers. And preview correctly when the display is profiled (and calibrated). IF the number are such that the image is too dark or bright, you FIX the numbers. You don't lie to the CMS or adjust your display brighter or darker.

Now if you wish to use a Kitchen Knife as a screwdriver when you have a perfectly good screwdriver (Photoshop), knock yourself out. But to suggest to others it's a sensible tool, after misunderstanding basic color management in terms of the Assign Profile command, someone should (and did) call you out for this falsehood. I explained what is happening under the hood with this 'false profile' and how it buys you nothing and as yet, you've not disputed those data points based on how a CMS actually works. Nor can you. So I'll leave it to others to decide if what you propose makes any sense based on how color management in Photoshop and other applications really work.

Lastly I'll leave you with a quote from the late, great Bruce Fraser (who knew more about Photoshop and color management than anyone here) with respect to this silly idea of Dan's (and BTW, in the very old days of the Compuserve PhotoForum, Bruce regularly proved Dan's arms were way too short to box with him):

"You can do all sorts of things that are fiendishly clever, then fall in love with them because they're fiendishly clever, while overlooking the fact that they take a great deal more work to obtain results that stupid people get in half the time. As someone who has created a lot of fiendishly clever but ultimately useless techniques in his day, I'd say this sounds like an example."

Last edited by andrewrodney; 02-09-2017 at 04:59 PM.
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  #19  
Old 02-09-2017, 04:35 PM
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andrewrodney andrewrodney is offline
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Re: ICC false profiles for color grading/correctio

Further educational reading on Assign Command if you wish to undertake that path:
http://digitaldog.net/files/06AssignProfileCommand.pdf

And further education viewing of video how the Color Settings affect previews and how the Assign Profile command operates:

Photoshop CC's Color Settings & the Convert to Profile and Assign Profile command.

This new video covers everything you thought you wanted to know about the Photoshop Color Setting dialog. It also discusses the Convert to Profile Command and the Assign Profile Command. Photoshop CC 2017 is used in this video and it updates the video on this subject I Published on June 28, 2012.

High Rez: http://digitaldog.net/files/PhotoshopColorSettings.mp4
Low Rez (YouTube): https://www.youtube.com/watch?v=6JaHOGDK5OI
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  #20  
Old 02-09-2017, 05:00 PM
Shoku Shoku is offline
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Re: ICC false profiles for color grading/correctio

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Originally Posted by andrewrodney View Post
Further educational reading on Assign Command
You just don't get it. There are many ways to skin a cat, or to retouch (adjust) an image. An experienced retoucher uses the tools that work, and sometimes this means doing things others don't do because it either saves time, or leads to a better result.

There are two aspects to being a good retoucher: the first part is to understand the technical concepts behind the tools you use, and the other part is how to apply what you know with enough artistic perfection to please your client.

We (my company) not only need to color manage on our end, but also determine what our clients did on their end. The majority of our clients know nothing about color management, so we are presented with a mystery about 60% of the time we open a file.

Based on your responses I think you need to focus on my stated results instead of keeping your head in the technical swamp, because it's blinding you to real world possibilities that work.
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