I'm not sure what is involved when you say "Edit" the profile. You cannot just change the white point leaving the same cromaticity values. If you do that you end up with a non-neutral color space (where R=G=B =/= neutral). You should perform chromatic adaptation to the cromaticities (such as Bradford) either to the color profile or the image to a common white point before comparing color spaces.
Yes, I fully agree and may have misunderstood the earlier comment. The main point of the OP was that, even though the DCraw profile is not standard, images from an application would look the same provided it is color-managed. Thus a D65 "PhotoPro" should work, with that proviso. In creating the comparison image in my earlier post
, I did use a profile converter, which I can only assume applies chromatic adaptation, set to relative colorimetric intent.
My understanding from DCRaw, is that it uses profiles adapted to D65, (and it is true that starts with a conversion to sRGB) so further conversions do not require "cromatic adaptation" (this seems to be a rather common approach, according to the quote from Bruce Lindbloom at the end of this message).
That is also my understanding.
Also in DCRaw, the gamma is not really 1.92 but a TRC function corresponding to the standard B.T. 709, with an initial slope of 4.5 and then a gamma correction of 2.222, but you could specify your desired parameters with option -g power toe_slope. In any case, it seems that all calculations are performed in linear space and TRC is applied just before writing the output file.
That is indeed the default correction. Thank you for the -g clarification - I had thought it was peculiar to sRGB, we live and learn (slowly, at my age). I got the odd gamma number from ColorThink's Profile Inspector which reported rTRC as "Gamma-defined curve Value = 1.92" which, in my naivety, I took as correct.
A couple of years ago there was a rather long thread about color space conversions
here in Lu-La, where I posted a response from Bruce Lindbloom (with his permission) from an equiry, which I think it is relevant for this discussion
Thanks for the link to the relevant topic, which I will read avidly, and I had Bruce's site already bookmarked and use his calculator a lot but many of his writings hurt my brain ;-)
In ColorThink V2, A comparison of Adobe 1998 vs, ProPhoto does indeed show Adobe sticking out of the 3D upper surface on the blue side but only because of the different white point. Not surprisingly, Dave Coffin's profile encompasses Adobe 1998 quite nicely!