Recently, I’ve been messing with baking white balance into my camera profiles. By way of background, most tutorials about making camera profiles tells you to shoot the target, then develop it to a TIFF including white balance correction. Based on recent discussions here, I decided to try making target TIFFs without white balance correction, and let the conversion from camera space to a working space like Rec2020 also handle the chromatic adaptation from camera white to the working profile’s white point. For grins, here’s the XYZ media white point of such a camera profile:
[ICC_Profile] Media White Point : 4.89584 5.11565 4.00757
The color management library I’m using in my programs, LittleCMS, does the chromatic adaptation from that wild triplet to the destination’s white point, then it does the color transform. Sounds weird, but it does work.
Thing is, XZY/D50 as the intermediary keeps me from having to develop a different camera profile for every destination space. Not so bad for going to a working profile, but displays and printers all have their particular white points, so some common ground color space and white point is needed to keep from having to maintain a rat’s nest of device->device transforms.
It didn’t have to be D50; they could have picked D65, or some other triplet. The key point is, they picked one, and all parties know what it is…