Part of Item:
Comment Type: TE
Comment (including rationale for proposed change):
These comments also apply to 1.4.1:
1. Is it realistic to expect authors to do the math to figure out the luminosity contrast ratio?
2. Why isn\'t MathML used to represent the equations?
3. If the only difference between 1.4.1 and 1.4.3 is the ratio (5:1 vs 10:1), then drop one ratio and therefore one needless requirement.
1. Use MathML to represent the equations.
2. Eliminate either 1.4.1 or 1.4.3, preferably the latter.
3. Reconsider the expectation that authors will determine contrast through the use of the luminosity contrast ratio. Did anyone in the working group poll authors to see if this is realistic?
Authors do not have to use the luminosity contrast ratio to determine their contrast ratio. In the resources section, a list of tools have been provided that already do this. One uses an eye dropper and is very easy to use. We have added a note to the intent sections of both SC 1.4.3 (formerly 1.4.1) and SC 1.4.5 (formerly 1.4.3) that refers to the list of these tools to make it more obvious that these tools are available.
Because support for MathML varies across browsers and platforms, because the information from the equations can be mis-presented in some cases, and because it was possible to represent the luminosity contrast ratio in ASCII, a MathML version of the equations was not included in the guidelines themselves. We have, however, added a note to the definition which points to a MathML version. Should support MathML change prior to publication, we will include this version in the guidelines themselves.
The working group determined that there is a significant improvement of readability between 10:1 and 5:1 but that 5:1 was sufficient in most cases and 10:1 is very demanding, basically white on black or vice versa.