Contrast Ratio Math and Related Visual Issues
# _Note (Jan 2023):_ _This thread is mainly the **very early research notes** and discussions that lead to the development of certain perceptually uniform contrast methods. While of interest from a historical perspective, the most current understanding of perceptually uniform contrast can be found at the [Contrast Resources](https://git.myndex.com) page, and current discussions in the [APCA forum](https://github.com/Myndex/SAPC-APCA/discussions)._ _The initial conclusions did not present themselves until the first several months of posts, around the time of [initial fixes described in May 2019](https://github.com/w3c/wcag3/issues/192), however the present day body of knowledge is substantially improved beyond that point._ _As such, this thread remains here as a matter of historical interest only, and should not be referenced directly. For a reference, a good current overview is [**this article**](https://www.smashingmagazine.com/2022/09/realities-myths-contrast-color/)_ _Thank you for reading,_ — _Andy_ _Andrew Somers_ <sub>_W3C AGWG Invited Expert_ _Research Lead, Visual Contrast_ _Color Scientist @ Myndex Research_ </sub> ----- ## _Original Post of April 2019:_ The W3C's specification for determining sRGB contrast as discussed in "Understanding WCAG 2.0 and 2.1, Minimum Contrast 1.4.3" is not perceptually uniform and as a result creates "contrast ratios" that are not meaningful. The end result is incorrect contrast choices for some web colors. Compoundin
Posted by Myndex on Apr 14, 2019, 10:52 AM
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[Meta] Feedback on granular control over Copilot changes
unexpected status 401 Unauthorized issue
[MODEL] Measurable quality regression in Claude generation 5 (Fable 5 / Opus 5 / Sonnet 5): worse nonsense detection, ~2x verbosity, under-disclosed model fallb
[CRITICAL] Subagent spawning and subagent pattern bugs trigger infinite recursion, infinite token usage, grossly inefficient token usage, and lost accumulated s
Video stops playing after some minutes
[MODEL] Claude verbose code comments by default — ignores instructions to stop.
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Contrast Ratio Math and Related Visual Issues
# _Note (Jan 2023):_ _This thread is mainly the **very early research notes** and discussions that lead to the development of certain perceptually uniform contrast methods. While of interest from a historical perspective, the most current understanding of perceptually uniform contrast can be found at the [Contrast Resources](https://git.myndex.com) page, and current discussions in the [APCA forum](https://github.com/Myndex/SAPC-APCA/discussions)._ _The initial conclusions did not present themselves until the first several months of posts, around the time of [initial fixes described in May 2019](https://github.com/w3c/wcag3/issues/192), however the present day body of knowledge is substantially improved beyond that point._ _As such, this thread remains here as a matter of historical interest only, and should not be referenced directly. For a reference, a good current overview is [**this article**](https://www.smashingmagazine.com/2022/09/realities-myths-contrast-color/)_ _Thank you for reading,_ — _Andy_ _Andrew Somers_ <sub>_W3C AGWG Invited Expert_ _Research Lead, Visual Contrast_ _Color Scientist @ Myndex Research_ </sub> ----- ## _Original Post of April 2019:_ The W3C's specification for determining sRGB contrast as discussed in "Understanding WCAG 2.0 and 2.1, Minimum Contrast 1.4.3" is not perceptually uniform and as a result creates "contrast ratios" that are not meaningful. The end result is incorrect contrast choices for some web colors. Compoundin
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