These profiles are useful for determining system color behavior. If the vcgt tags are loaded into the video LUTs, the brightness of the monitor will abruptly change. If a profile is loaded that has no vcgt tag, you can see if the video LUT is left alone or if some default curve is loaded instead.
These profiles are probably more useful in a relative sense than in an absolute sense. By that I mean you may compare behavior (video LUT, OS color handling, application color handling, etc.) with one profile loaded vs. a different profile loaded. This will help you discover which parts of the profile are being used by different parts of your computer system. This particular set of profiles allows you to vary one attribute at a time, which will help isolate the iteractions between the vcgt gamma and the RGB gamma.
The set includes six profiles:
| Profile Name | vcgt Tag Gamma |
rTRC, gTRC, bTRC Tag Gamma |
| A.icc | no tag | 1.0 |
| B.icc | no tag | 2.2 |
| C.icc | 1.0 (null) | 1.0 |
| D.icc | 1.0 (null) | 2.2 |
| E.icc | 1.0 / 2.2 | 1.0 |
| F.icc | 1.0 / 2.2 | 2.2 |
They are available as downloads in either zip (4K) or sit (4K) format. The download includes a Read Me file that explains everything.