On Jul 6, 2013, at 11:24 AM, Maciej Bryński <maciek@xxxxxxxxxx> wrote: > I can manually approximate correct WB. But is there a method to count > it exactly ? Yes and no. You can precisely normalize white balance and exposure both by building a profile of a UNIWB gamma 1.0 development of the file; looking up D50 white in said profile; and doing a bit of math on the resulting RGB values. The catch is twofold. First, I have no clue what sorts of math would be necessary to translate into some white balance / tint slider positions; second is that I don't even know if C1 offers the ability to do the kind of minimalist processing you need. (Basically, you're looking for a file that's undergone demosaicing and nothing else.) If you can't do it right, you can at least get pretty close by cranking the saturation, fiddling with the sliders until it looks as least awful as you can get, and returning the saturation back to normal. It helps to have a synthetically-generated reference image on the same screen to compare with. You'll also want to adjust the exposure slider so that the luminance of neutral patches are as close a fit as possible, and you'll likely want to bounce back and forth between adjusting white balance and luminance until you reach a point of diminishing returns. Boosting saturation visually exaggerates color differences, especially of those close to the neutral axis. An image whose white balance is even slightly off will look really bad when you crank the saturation. If the white balance is perfect, it'll just look very saturated. More details -- too many more details -- here: http://trumpetpower.com/photos/Exposure Cheers, b&