Color profile and presets that don't make any changes to the raw file

[Sharam55]

My goal is to evaluate the improvement in color accuracy by creating and applying my own custom profile. In order to assess the improvement, I need to compare two images with and without the application of my custom profile.

I created a custom profile for my Camera by using X-rite ColorChecker Classic and ColorChecker Camera Calibration software.

To get the colors that are produced by my camera, I need to turn off all presets and profiles that are automatically applied to the image by Adobe Camera Raw.

By default, ACR uses Adobe Color profile. There are other profiles under Adobe, Camera Matching, Legacy available to me. I need a “Null Profile”. In other words, a profile that does absolutely nothing to the raw file. How can I create one if Adobe does not provide one?

Under Legacy, I also see ACR3.3 and ACR4.4 profiles. Are these suitable for what I am trying to achieve?

Can I manually edit the profile file and set all changes to zero?

Thank you for your help.

[D Fosse]

There is no such thing as a "null profile", just as there is no such thing as an "original/untouched" raw file.

A raw file has to be processed to produce an image at all. The camera profile is part of that processing. There is no reference version of the image - what you see on the camera LCD is just the manufacturer's processing, their choices, no "truer" than anything else.

If you could see the raw file directly, it would be a very dark, very flat and tonally compressed monochrome image. You wouldn't recognize it. But that's how the sensor records it.

Looking for an objective colorimetric standard here is an exercise in futility. You'll never get there. If you got an acceptable result in one scenario, it would be off in another. If you need to get close to colorimetric accuracy, you need to do that in an output-referred context (an RGB file), not a scene-referred context (camera profiles).

That's not to say camera profiles can be anything at all. But it's a subjective decision, not an objective reference.

[Sharam55]

Thank you for your response. I think I understand what you are saying.

Suppose I want to photograph a painting and I want to reproduce the original colors of the painting illuminated with a certain light. How do I create a profile that is faithful to the original lighting? In other words, I want to avoid or at the very least minimize ACR making changes to my colors.

Thank you in advance.

[TheDigitalDog]

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@Sharam55 wrote:

Thank you for your response. I think I understand what you are saying.

Suppose I want to photograph a painting and I want to reproduce the original colors of the painting illuminated with a certain light. How do I create a profile that is faithful to the original lighting? In other words, I want to avoid or at the very least minimize ACR making changes to my colors.

Thank you in advance.

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 A custom DCP profile for the illuminant is a good first start:

Everything you thought you wanted to know about DNG/DCP camera profiles:
All about In this 30 minute video, we will look into the creation and use of DNG (.dcp) 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%20Camera%20profile%20video.mov

You may want to read this too, since you're nearly always producing output referred images:

http://www.color.org/ICC_white_paper_20_Digital_photography_color_management_basics.pdf

[D Fosse]

Suppose I want to photograph a painting and I want to reproduce the original colors of the painting illuminated with a certain light.

By @Sharam55

I work as photographer at an art museum and I do this all the time. I gave up on the idea of colorimetric accuracy a long time ago. Even if you can get there, it won't look good, and above all, it won't look right. It takes so much tweaking that you lose all semblance of internal consistency, it will just look disjointed and fragmented.

What I aim for is equivalent and credible color, not accurate color. But that will be accepted as accurate, because it gives the viewer the same visual experience as seeing the original. Within context, of course.

I do use a color checker in the shot, but mainly for the six neutral patches, which I use to set the contrast curve, white point and black point. The rest is subjective choices. Yes, it's tricky, and yes, experience helps a lot 😉

But once I have my file, color management procedure is religion. A top notch monitor, calibrated and profiled with great care, is absolutely required.

[Sharam55]

Thank you thedigitaldog and D Fosse.

My first attempt by using the X-Rite ColorChecker Camera Calibration has been disappointing!

I am comparing the same image with a reference target. I have two images one with and one without calibration.

[Sharam55]

Has anyone had experience using "Lumariver Profile Designer"?

Their Pro version can be used to make DNG profiles for reproduction work.