I understand how to make the DNG profile and restart Lightroom. Then go to Camera Calibration, select the profile of the particular lens/camera operation, and look at it. NOW, after that, what do you do with it. If it is just "tweak" it, well that is just more subjective stuff. Can someone explain what to do with the special profile?
In my very limited (2 camera bodies) experience with the DNG profile system, what I have found is that the Color Checker-generated profile does not provide 'perfect color' upon it's application to the file, but gets me closer... as a
starting point for further adjustment.
Some more random thoughts:
The best way to see the color rendering differences between lenses is to look directly through them, by eye, at a sheet of white paper that is illuminated by neutral daylight. There, I have marveled at the distinct greeenish-yellow of many older, pre multi-coated lenses, the neutral to very slight green-blue color of most modern Nikon and Canon lenses, the pale lemon-yellow look of Leica M lenses, and the warm, orangey color from the Zeiss lenses.
Does this eye-looking have much to do with how the shots will look after digital post production? No....especially now, with wide-range correction available in digital post.
All of the differences that you can see by eye are reduced and/or modified by every stage in the post production processing of the photo: Raw converter, color and density adjustments, jpeg compression(if applicable), assigned [smaller] color spaces, and the final viewing medium: cheap laptop TN display, or luxurious color-calibrated ARGB monitor, or...printed on paper with a neutral white base, or a warm-toned base, using Canon ink or Epson ink, etc, etc.
Light sources: A comparison of color rendering of the lenses done under one specific light source applies to that light source, but maybe not to another light source. Especially in the case of LEDs and fluorescents tubes. LEDs and Flo tubes change over time, almost always toward the green.
This company,
http://www.cineolighting.com, claims to have ameliorated some of the color issues with LEDs with what they call "Remote Phosphor" design.
I have used their units in television production, and they are heavy but well made. Did we conduct complicated, exacting tests of their light quality? No. We did like we always do: we look at the shot in a known, high-quality monitor, adjust the color response of the camera if necessary, and if it looks nice, we shoot it.