C1's general-purpose profiles are not intended for absolute color accuracy. They are designed for overall balance between accuracy, pleasing color, and robust response under different illuminants. Having a lot of experience with accurate color reproduction, I can say confidently that most users would not enjoy if they got truly accurate color. Most photographers, if you ask them, will say they want an "accurate/neutral starting point" so they can add their own salt and pepper, but only because they've never seen a truly scientifically accurate color profile applied to a general-purpose scene.
P1 does produce some extraordinarily high-quality profiles designed exclusively with accuracy in mind (for art reproduction and other cultural heritage and scientific use) that are part of the Capture One Cultural Heritage Edition. In such applications, aesthetics and human preference are irrelevant; it's the mission of the process to exactly reproduce the physical object. You can, of course, also make and use your own profiles either by starting with the canned profile and modifying it using Color Editor and then resaving it (as an ICC profile) or by third-party software. Our Reflective Digitization Guide covers doing so with BasIIColor (our suggestion) or there is also a version of X-Rite software now that can do this for C1. But as you know making your own profiles is a process fraught with false-positives and prone to create fragile profiles that test well, but do less well in the real world.
Doug, I can't quarrel with anything you said there. For serious work, I do like to start with a fairly accurate image (with the cameras available to us, near-perfect accuracy is beyond our reach no matter how good the profiles), but I realize that I'm in the minority.
And you are entirely correct to point out the importance of the illuminant in profile making -- and photography in general.
But I brought up accuracy in the context of the assertion that C1's profiles were "
far* better" than Lr's. Once you say that you're not trying to produce accurate colors, or even accurately viewing-conditions-adapted colors, but are trying to make pleasing colors, the definition of whether you succeeded will depend on the viewer. So saying without defining the test methodology that one raw developer's profiles are better or worse than another's is meaningless.
It seems like there is a race to ever more chromatic default profiles, and I think that's a step in the wrong direction. Most of the amatuer images that I see in photo fora are way too punchy for me, and it seems to get worse with each passing year.
Jim
*Italics from the original poster of the phrase.