Analysis of table below:
I find that Gateway 1.4.1 does not address Guideline 1.4. I think motion and contrast are separate issues. I find that Gateway Task 1.4.2 is redundant with Guideline 1.4 and therefore unnecessary.
Gateway 1.4.2 goes into an explanation of the reason contrast is important.
"Many people see disabilities as absolute, people are either completely impaired or not at all. This is not the case, the vast majority of disabilities are partial disabilities, people having a range of ability. As such it is important that people with a partial disability can differentiate between content and background. In auditory content this means good sound quality and that background noise is kept to a minimum. Visually users have a variety of contract needs. Some users also have issues with color. See section on color."
I suggest this paragraph needs work. First of all I think saying things like "completely impaired" and "partial disability" is problematic. I presume it is referring to someone who is partially sighted rather than completely blind. I understand the intent but I don't think it works.
The CSS 2.4 technique says "use numbers, not names for colors" This is not a direct hit on Guideline 1.5 although its title is "Color Contrast". I also wonder why using color names is problematic. Perhaps the author was thinking of future tools that would be able to measure RGB values but any tool like that should be able to convert color names to their HEX values. I think we could drop that CSS technique (2.4)
CSS techniques 2.7 addresses Guideline 1.4 but appears to me to be general in nature and as such could be part of the Gateway rather than CSS. (only *if* we had seamless integration between the documents ) CSS 2.8 address Guideline 1.4. Again it appears to start off with a technology independent suggestion which could move to the Gateway.
|Guideline 1.4||“In visual presentations, make it easy to
distinguish foreground words and images from the background.”
||Task 1.4.1"ensure that visual motion does not make content unreadable.”||None||2.4 Color Contrast
Use numbers, not names, for colors.
|Task 1.4.2 “Ensure that foreground content is easily differentiable from background for visual presentations”||
2.6 Foreground and background contrast
Ensure that foreground and background colors contrast well.
To test whether color contrast is sufficient to be read by people with color deficiencies or by those with low resolution monitors, print pages on a black and white printer (with backgrounds and colors appearing in grayscale). Also try taking the printout and copying it for two or three generations to see how it degrades. This will show you where you need to add redundant cues (example: hyperlinks are usually underlined on Web pages), or whether the cues are too small or indistinct to hold up well.
Editorial Note: Still want to recommend this test? Instead could recommend brewer palette or other techniques.
|Success Criteria 1:||Any text that is presented over a background is electronically available so that it could be re-presented in a form that allows the text to be distinguished from the background. [I]||All CSS separates presentation from content|
|Success Criteria 2:||Text that is presented over a background has a contrast greater than ____ between the text and the background as measured by ___ or the resource provides a mechanism to allow the text to meet this criterion. [V]||
2.7 Specifying fore- and background colors
If specifying a foreground color, always specify a background color as well (and vice versa).
|Success Criteria 3:||This item should read identically to level 2
item #1, except that it should say "in default presentation mode." [V]
Text is not presented over a background image or pattern, or if a background image or pattern is present, the text is easily readable when the content is viewed in grayscale to determine if the background makes it difficult to identify individual characters. [V]
2.8 Conveying information through multiple means (not just color)
Ensure that information is not conveyed through color alone
For example, when asking for input from users, do not write "Please select an item from those listed in green." Instead, ensure that information is available through other style effects (e.g., a font effect) and through context (e.g,. comprehensive text links).
|Informative||Who Benefits from Guideline 1.4 (Informative)
Individuals with low vision can easily read characters in the content even if they don't have the wide field of view or full range of color perception used by fully sighted persons to separate text from background images.
Examples of Guideline 1.4 (Informative)
Example 1: a background image on a page.
A background image and text are arranged so that there is no image behind the text or the image is so faint that the difference between the darkest part of the image and the text (which is dark) meets the standard foreground/background contrast requirements. The image behind the text also does not contain lines that are about the same width as the characters so they do not interfere with character recognition.
|Many people see disabilities as absolute, people are either completely impaired or not at all. This is not the case, the vast majority of disabilities are partial disabilities, people having a range of ability. As such it is important that people with a partial disability can differentiate between content and background. In auditory content this means good sound quality and that background noise is kept to a minimum. Visually users have a variety of contract needs. Some users also have issues with color. See section on color.|