G145

Notes on the WCAG Technique Sections

I guess no mobile-specific change is needed. A more general concern is that especially on mobile screens the advertised point size is rarely the same as the actual point size on the display (measured with a typometer). So it stands to reason that the description and the test should help determining whether the general value of 4,5:1 should apply or the relaxed value of 3:1 is sufficient. The measured point size threshold made differ between desktop screens, tablet screens and smartphone screens due to the difference in their respective average viewing distance. Whether this needs to be part of every technique or be subject to a general note somewhere, I am not sure.

• Applicability: no change
• Description: no change
• Examples: no change
• Resources: no change
• Related: no change
• Tests: no change

- Detlev Fischer, 20 Aug 2014

Suggested edit at the end of section Description:

Note: On mobile devices, the typeface point size which can be set via systems settings usually does not match the actual point size on the display (as measured with a typometer). Where possible the threshold for determining whether the requirement for a contrast of 4.5:1 or 3:1 should be applied to content should refer to desktop versions as seen on a typical monitor.

(A formula for hands-on conversion for a different threshold to apply for tablets and smartphones and their relative typical viewing distance might be provided here. Note however that many LV users get ver yclose to their device, whether desktop screen, tablet, or notebook, so viewing distance may be a debatable factor for relaxing size requirements where 4.5 kicks in.)