On Tue, Mar 28, 2017 at 3:49 PM, Per Östlund <[email protected]> wrote: > Hi, > > I've digitized my father's collection of old slides with the camera + macro > lens + light table method. Most of the images look fine, but some images > with certain blue hues are giving me a headache. I'm guessing the issue is > that the light table I built used LEDs with a poor color spectrum for the > task, causing the blue channel to blow out.
> As soon as I touch e.g. the levels module I get the usual issue that very > saturated blues turn black. > Using the gamut clipping option in the input > color profile module fixes that particular issue, but doesn't do anything > for the colors otherwise. Setting gamut clipping in input color profile is the proper fix here. > The best solution I've managed to come up with so far has been to set the > input color profile to "linear Rec709 RGB" which heavily desaturates the > image, and then increasing the saturation a lot with the color correction > module. Hardly an optimal solution, but with some tweaking I can usually get > the colors to look approximately the same except that the blues don't clip > anymore. *Why* don't you like the gamut clipping solution? As you said yourself, it "doesn't do anything for the colors otherwise.". > This method can require quite a lot of tweaking to look good though, so my > question is if someone knows of a better way to handle this issue (besides > reshooting with a better light source). Here's an example RAW-file (don't > mind the blur, that's from the original slide): > https://www.dropbox.com/s/6mshjycwm4n10xa/img_014.ARW?dl=0 > > Regards, > Per Östlund Roman. > ____________________________________________________________________________ > darktable user mailing list > to unsubscribe send a mail to [email protected] > ____________________________________________________________________________ darktable user mailing list to unsubscribe send a mail to [email protected]
