ICC false profiles for color grading/correction

[Guest]

Hi,

I run across this old article about false profiling: "the generation and intentional assignment of a false profile to an RGB file with the idea of fooling Photoshop during subsequent colorspace con versions".

One can control gamma, white balance and RGB primaries (xy) to create a false profile to color grade the image without going about the usual Photoshop tools. Also, in a master file different icc versions of the same photo can be locally revealed and hidden through masking.

Do you think this old and unusual method can still provide a solid way for color grading?

Thanks

[andrewrodney]

Re: ICC false profiles for color grading/correctio

There is no such thing as a "False Profile".
You're not doing anything special or useful; a conversion takes place between the color spaces at some point. All you're doing is altering the preview when you assign a profile to data. The data doesn't change until and when you convert to some other color space. Then, the edit applies and the edit could have been applied using any other 'standard' Photoshop tools (like curves).

This is akin to taking an image that appears too dark and cranking up the brightness on your display.

[klev]

Re: ICC false profiles for color grading/correctio

That sounds way too complicated. I don't like overly convoluted hacks. Even if they appear to generate acceptable results under normal circumstances, they tend to break in unexpected ways.

[Guest]

Re: ICC false profiles for color grading/correctio

There is no such thing as a "False Profile".

By the way, I wonder if there is a way to abotain this discontinued plug-in for CS5 under windows: Kodak Colorflow Custom Color Tools.

Then, the edit applies and the edit could have been applied using any other 'standard' Photoshop tools (like curves).

Yet, anytime an edit is applied to a pixel (curves et al) numbers are altered resulting in data loss or "quantization errors" (depending on bit depth). Does converting from the "artistic" profile to "regular" profile (Adobe RGB) cause the same loss?

Thanks

[Tony W]

Re: ICC false profiles for color grading/correctio

If you look at the images displayed in this 15 year old article you may find that there is nothing shown that cannot be achieved simply in more recent versions of PS e.g. using curves and/or hue sat layers without jumping in and out of different profiles. In fact I am not too sure that they could not have been done at the time in CS2 without the profile jumping

AFAIK, as I have not used it, the Kodak Colorflow tools were designed for altering ICC profiles. If you can still get hold of it there is no guarantee that it will still function with newer versions PS.

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

[Guest]

Re: ICC false profiles for color grading/correctio

If you really want to play around with profiles you may want to investigate Adobe DNG profile editor (FOC)

I believe that is not my kind of thing: I'd rather go with ArgyllCMS. Yet, Kodak plug-in would be THE one.

[Tony W]

Re: ICC false profiles for color grading/correctio

I believe that is not my kind of thing: I'd rather go with ArgyllCMS. Yet, Kodak plug-in would be THE one.

Argyl/DNG does pretty much the same thing.

Want a plugin rather than manual adjust using PS have you looked at 3D LUT Creator?

http://3dlutcreator.com

[Guest]

Re: ICC false profiles for color grading/correctio

Want a plugin rather than manual adjust using PS have you looked at 3D LUT Creator?

Also really cool. Yet, being based on CS5 I am not able to load .cube 3d luts profiles. Unless, there is an affordable way to convert 3d lut to icc.

[Tony W]

Re: ICC false profiles for color grading/correctio

Also really cool. Yet, being based on CS5 I am not able to load .cube 3d luts profiles. Unless, there is an affordable way to convert 3d lut to icc.

Ahh, yes CS5 will be a problem, I do not think you could use LUTS in the same way you can with CS6 and later.

TBH, I cannot see that you will be at a loss to use either DNG convertor or Argyl if that is your preference. As long as you know which way your images need to go and it is worth making a new profile either should do the job.

Not used Argyl as so far Adobe DNG pretty good for the job in hand. Assuming that you are not wanting to go for accurate or even necessarily pleasing colour (that is what they were designed for) but rather an effect that you can automatically apply to other images then why not give them a try?

Quick play with no particular direction in mind producing my own PSP's (Pretty S*** Profiles) version 1 and 2 above and below original attached.
Could have done the same in PS of course and in these cases pretty easy

[andrewrodney]

Re: ICC false profiles for color grading/correctio

By the way, I wonder if there is a way to abotain this discontinued plug-in for CS5 under windows: Kodak Colorflow Custom Color Tools.



Yet, anytime an edit is applied to a pixel (curves et al) numbers are altered resulting in data loss or "quantization errors" (depending on bit depth). Does converting from the "artistic" profile to "regular" profile (Adobe RGB) cause the same loss?

Thanks

Custom Color ICC is a profile editor and a superb one at that but is no longer supported, sold or will run in Photoshop (I have a copy that still runs on an old Mac under Photoshop CS2).

[andrewrodney]

Re: ICC false profiles for color grading/correctio

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

[Shoku]

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.

[andrewrodney]

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 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!

[Shoku]

Re: ICC false profiles for color grading/correctio

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.

[andrewrodney]

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