My Color Combo Passes WCAG – So Why Does It Still Hurt to Look At?
medium.com> Tools like APCA improve contrast modeling, but they still don’t account for halation, ambient light mismatch, or eye strain.
Doesn't APCA advocate a maximum contrast? Best link I could find right now is https://github.com/Myndex/SAPC-APCA/discussions/106 but it lacks explanation. If it doesn't account for the above, any ideas what APCA means by maximum contrast then and why the above was overlooked?
My understanding is this:
- APCA does define a “maximum contrast” (currently set at Lc −90 for dark-mode text) to prevent extremes that actually hurt readability.
- But that limit exists purely to guard accessibility - i.e. ensure text remains legible - not to model all factors of visual comfort. APCA’s core goal is “readability contrast” not halation, ambient-light mismatch, or eye-fatigue.
So yes: what’s accessible (legible) often overlaps what’s comfortable, but it doesn’t guarantee it. The "Color Comfort Score" aims to pick up where APCA leaves off, by folding in those extra perceptual and environmental factors.
If white on black text causes any eye strain at all then you need to adjust your monitor, not make the text gray.
Dimming the monitor just turns white into gray globally. It lowers overall luminance, but doesn't fix the relative contrast or the perceptual glare caused by high-contrast elements like pure white on pure black.
In fact, even at lower brightness, bright-on-dark can still cause halation, retinal fatigue, and visual vibration, especially in low-light environments.
Designing softer contrasts does the same thing, but more intentionally - and we can't assume users have ideal screen settings. Better to design for humans, not hardware.
Also: white-on-black is just one example.
Contrast does not cause fatigue or eye strain. Brightness does. If your monitor is hurting your eyes, turn it down. Don’t rely on a designer to use gray text so that it doesn’t hurt your eyes, adjust the brightness directly to the level that is comfortable for you.
Eye strain has many causes - brightness plays a role among other factors as described. If a design requires users to tweak their monitor to feel okay, it's not a good design.