- From: Chris Lilley via GitHub <sysbot+gh@w3.org>
- Date: Sun, 27 Feb 2022 17:27:05 +0000
- To: public-css-archive@w3.org
> LAB goes to cone space using "wrong Kries", but this leads to the conversation regarding the utility of transforming into cone space as a practice to model tristimulus displays with very narrow bandwidth primaries. CIE Lab does _not_ go to cone space, this statement is incorrect. OK Lab _does_ go to a cone space. The much quoted "wrong von Kries" in CIE Lab only applies if someone goes into Lab with one white point and goes out again with a different white point, which no-one does nowadays; instead they use a CAT (typically Bradford, which CSS color 4 mandates). CIE LUV has the "very wrog XYZ scaling" adaptation problem, even worse than an incorrect von Kries. But again, easily avoided by using a proper CAT. > CIELUV also does not do the purple shift. LUV is not in cone space, it's in "illuminant space" which is convenient for self-illuminated monitors... 😳 CIE LUV does exhibit the purple shift. Dragging things back to the CSS Color 4 specification, the purple sift was dealt with by using OKLCH as the space for gamut mapping and OKLab as the default space for interpolation. This also avoids a D65 to D50 adaptation step, as OK uses D65. -- GitHub Notification of comment by svgeesus Please view or discuss this issue at https://github.com/w3c/csswg-drafts/issues/6061#issuecomment-1053622790 using your GitHub account -- Sent via github-notify-ml as configured in https://github.com/w3c/github-notify-ml-config
Received on Sunday, 27 February 2022 17:27:06 UTC