This is, even at a glance, obviously much better looking. However - I came across some interesting issues with other photos in this set, which suggests to me that I need to refine how I'm producing profiles.
That profile was created using the colprof command:
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colprof -v -D"2013-05-23" -al -qm DSC_0225 -O 2013-05-23.icc
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-al - produces a cLUT profile, with a PCS (Profile Connection Space) of L*a*b*; Argyll recommends this as generally producing the best results
-qm - Default quality, also recommended
Most of the image looks great, but the very bright yellow obi on the left was corrected to be overly bright, resulting in some really bad, ugly clipping. The colours weren't actually clipped in the original photo, so this is a problem with how the colour profile was generated.
I experimented with a few other profile types Argyll supports:
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-am - produces a profile with linear gamma, which is specifically listed as being useful for raw photos.
-ax - produces a profile with a PCS of XYZ, which it says "may have the advantage of better accuracy for additive type devices (displays, scanners, cameras etc.), may avoid clipping for displays with a colorant chromaticity that can't be encoded in L*a*b* PCS space, and may give a more accurate white point for input devices by avoiding clipping of values above the white point that can occur in L*a*b* based cLUT input profiles"
-aX - a variation on -ax. Argyll says that "If it is important for both the cLUT and matrix be accurate, use -aX, which will create shaper/matrix tags."
-am:
-ax:
-aX:
There's no discernable difference between the output of -ax and -aX.
All of these produced great results, and it's difficult to tell the difference after converting to sRGB. Even in a larger space like ProPhotoRGB, the differences are very minor, mainly that:
- The colour tone of Madoka's pink shirt is slightly different (in -am it's a little deeper, whereas it's a little bit brighter in -ax/-aX). In -am it's about 247/184/207, whereas in -ax it's 255, 195, 222. This indicates that that colour region is being clipped in -ax.
- The purple-red background is darker in -qm, where it's about 197/88/102, than in -ax, where it's 206/84/105.
- The whites and lighter tone of the obi are brigher in -am than in -ax.
- The darker skin tones are darker in -ax than in -am.
Overall the colours in -qm appear to be more accurate to the real LD when I hold it in front of me. However, there's serious clipping in all of them - perhaps ProPhotoRGB simply isn't able to represent all of these colours? The original image, before converting, has no clipping beyond some light reflections on the very left edge of the obi.