Myndex

The Lighter Side of Dark Backgrounds

Is light text on dark harder to read than the more common dark text on white? Or are there other factors?

First, just as an FYI, dark backgrounds are a problem specific to the old WCAG 2 math/method. And for that matter, evaluating predicted contrast using some other ratio maths. And let's not forget: maths like Weber and Michaelson are about threshold, but readability is far suprethreshold, so those methods are not particularly useful.

Polarized Opinions on Polarized Colors

There isn't significant scientific consensus that goes much beyond user preference, and indeed some people (such as myself) much prefer reverse, light text on dark. The various dark mode extensions are quite popular for this. Also total screen luminance and the ambient lighting all are signficant here, and again one of the indicators of the importance of personalization.

Nevertheless, the old WCAG 2.x math badly mangles dark color pairs, in the randomized tests last year, dark color pair

Myndex

Will Work For Color

Color Manglement and Working Spaces.

A continuation of the Lab/Luv Gist

Let's not forget the many other color appearance models and methods. CAM02-UCS, RLAB, LLAB, IPT, CAM16 which is Luo's work in progress, etc. Many choices beyond the 44 year old Lab. The fact that Lab is one of the PCS used in ICC profiles is notwithstanding. If you look through profiles, you'll see that Lab is typically used as a PCS in profiles for CMYK and printing, while RGB space and monitor profiles use XYZ for the PCS.

Among other things, XYZ is computationally simpler than Lab. XYZ is infinite/unbounded••, you can transit through it without much penalty assuming the same source and destination illuminant (D65), here the fact the PCS is "D50" is essentially irrelevant: we are never really "in" D50, just passing through. Gamut mapping, soft clipping, etc. are usually not a huge concern going from a D65 RGB to another D65 RGB especiall

Myndex

Where's The Luv?

An Examination of the CIELAB and CIELUV colorspaces.

It is exciting to see so many new color features for the CSS Color Module. There are nevertheless a couple items that resulted in a "raised eyebrow response". This Gist is mainly going to focus on one: the use of the LAB version of LCh instead of LUV LCh, which may be better suited for the task but appears to have been dismissed as if irrellevant.

I DISAGREE. Luv is in common use and very relevant, and LuvLCh or one of the several LuvLCh variants has distinct advantages over LabLCh for use cases such as choosing color for web content for displays.

Myth Destruction