How did WCAG come up with the constants used in determining luminance
In https://www.w3.org/TR/WCAG20-TECHS/G17.html they used a few constants but I can't find where they're derived from
for the user experience design community
In https://www.w3.org/TR/WCAG20-TECHS/G17.html they used a few constants but I can't find where they're derived from