There are several questions on UX (e.g. here, here, here) already about contrast. However, all of those are about text, and the contrast between text and background, most off them referencing this W3 bit at some point. My question is slightly different, I want to know:
- Are there any standards for contrast between two solid color fills?
- How to measure this contrast (and possibly: color difference) between two solid color fills?
More specifically, I'm after the scenario where two adjecent blocks (with text) on a webpage have different solid background colors. For example:
#EEEE33 > #FFFFCC > #FFFFDD
Even more specifically, I'm looking for answers to help get an educated answer to this SO meta question about the contrast between background colors of tagged-interesting questions on the SE network. For example, the background color of favorited questions on UX vs SE:
Edit: In the picture above I'm interested in the background difference between a favorited and a non-favorited question (which for UX is quite a small difference, but for SO it's quite okay).
So, to summarize: what methods (standards? measuring techniques?) are available for difference in solid-fill background colors of adjecent blocks on a website?