ColorChecker, DCamProf, ART/RT

I have the Calibrite ColorChecker Classic Mini target. Using DCamProf, I created some color profiles for use with the ART (RT based) raw converter. I will share my experience.

The overall workflow is described here: How to create DCP color profiles

The DCamProf documentation is helpful, too.

1. It is crucial to avoid overexposing the highlights in color checker pictures. That was my main problem. You can use the Raw Histogram of ART/RT to check the highlights. Take a lot of pictures with different exposures and then select the best one.

2. In real life, it is often sufficient to use a single D50 illuminant color profile.

3. On my Linux system, argyll-scanin is called scanin (installed from the argyll package).

4. The path to the ColorChecher.cht file is also different: /usr/share/color/argyll/ref/ColorChecker.cht

5. X-Rite/Calibrate changed their formula in ColorCheckers produced November 2014 and later. cc24_ref.cie (from DCamProf) is for targets produced before November 2014. While cc24_ref-new.cie is for targets produced November 2014 and later. Therefore, I use the cc24_ref-new.cie file.

6. You can try the -s option with make-profile to use an alternate optimization algorithm.

7. Pay attention to the DE values in the make-profile result report. In my experience, they should not exceed 5. If the values are too high (10+), take another picture of the color checker.

8. It is better not to use an embedded tone curve for ART/RT. So I use the -t none option with make-dcp, and disable the "Look table" in ART/RT.

9. I also prefer to completely remove the "Look table" from a dcp file. I use the dcp2json and json2dcp commands of DCamProg; in the intermediate JSON, I remove the "ProfileLookTable" field.

10. Do not use the HueSatMap 3D (the -D option with make-dcp). In some cases, it can worsen highlight recovery in ART/RT.

See also related notes:

• Calibrite ColorChecker Classic Mini (2025-06-17)
• RawTherapee (2022) и ART (2022-03-30)
• Raw Therapee (2012-10-01)