MichaelG's suggestions from meeting

22/08/2023

Co-authored-by: Mike Gower <mikegower@gmail.com>

understanding/20/contrast-minimum.html

@@ -11,12 +11,12 @@ <h1>Understanding Contrast (Minimum)</h1>
    <section id="intent">
       <h2>Intent of Contrast (Minimum)</h2>
 
-      <p>The intent of this Success Criterion is to provide enough luminance contrast between text and its background, so that it can be read by people with moderately low vision or impaired contrast perception, without the use of contrast-enhancing assistive technology.
+      <p>The intent of this Success Criterion is to provide enough contrast between text and its background, so that it can be read by people with moderately low vision or impaired contrast perception, without the use of contrast-enhancing assistive technology.
       </p>
-      <p>For all consumers of visual content, adequate luminance contrast is needed between text and its background for good readability.
-         Many different visual impairments can substantially impact contrast sensitivity, requiring more luminance contrast, regardless of color (hue).
+      <p>For all consumers of visual content, adequate light-dark contrast is needed between the relative luminance of text and its background for good readability.
+         Many different visual impairments can substantially impact contrast sensitivity, requiring more light-dark contrast, regardless of color (hue).
          For people who are not able to distinguish certain shades of color &mdash; often referred to as <q>color blindness</q> &mdash; hue and saturation have minimal or no effect on legibility as assessed by reading performance (<a href="https://doi.org/10.1364/JOSAA.8.000428" title="Effects of chromatic and luminance contrast on reading">Knoblauch et al., 1991</a>).
-         Further, the inability to distinguish certain shades of color does not negatively affect luminance contrast perception (<a href="https://pubmed.ncbi.nlm.nih.gov/24103453/" title="Achromatic luminance contrast sensitivity in X-linked color-deficient observers: an addition to the debate">Márta Janáky et al., 2013</a>; <a href="https://link.springer.com/article/10.1007/s10792-018-0881-7" title="Contrast sensitivity of patients with congenital color vision deficiency">Cagri Ilhan et al., 2018</a>).
+         Further, the inability to distinguish certain shades of color does not negatively affect light-dark contrast perception (<a href="https://pubmed.ncbi.nlm.nih.gov/24103453/" title="Achromatic luminance contrast sensitivity in X-linked color-deficient observers: an addition to the debate">Márta Janáky et al., 2013</a>; <a href="https://link.springer.com/article/10.1007/s10792-018-0881-7" title="Contrast sensitivity of patients with congenital color vision deficiency">Cagri Ilhan et al., 2018</a>).
          Therefore, in the recommendation, contrast is calculated in such a way that color (hue) is not a key factor.
       </p>