I have a couple of guides to creating custom camera profiles for use in camera raw and lightroom, but they both involve using a Gretag card, which I don't have at the moment.
Does anyone have an alternative, reasonably accurate method for creating a custom profile for use in camera raw and lightroom?
The Rags Gardner scripts now support a variety of color targets so if you have one of those you could give it a try.
If you don't have ANY of those targets, then I think your only option is to eyeball it, maybe comparing to the output from DPP or an in-camera Jpeg. The whole point of the calibration process is to compare against a known standard so if you don't have that known standard, your results will be limited.
Since you have a 20D, I'll tell you what I came up with for my 20D using the Rags Scripts and the Colorchecker. I am still not totally happy with it and I want to re-do using the Q60, but the Q60 is a lot tougher to shoot because of reflections so I haven't gotten around to it yet. Anyway, for what it's worth:
Shadows +1
Red Hue -14
Red Sat +17
Green Hue -7
Green Sat +15
Blue Hue +1
Blue Sat -13
