[geori]

I'm very color blind and I don't think this extension correctly handles red-green color blindness. If you take a look at http://www.colourblindawareness.org/colour-blindness/ and see their examples of Deuteranopia, they are exactly what I see. When the app shows the Deuteranopia view, I think the extension modifies colors that aren't red and green.

[hellojason]

Forgive my ignorance, but how do you know that what these tools show is good or bad at representing what you see?

[OscarCunningham]

Presumably because the image looks to him exactly like the full-colour image.

[brianmcc]

Exactly: "normal" and "simulated" should be indistinguishable - and often, for me having reg/green deficiency, that's the case. I'll often look to confirm that images truly are different before using them as examples.

Colour deficiencies vary, though, so even a simulation that works perfectly for some is not going to be a universal simulation.

These simulations are amazing in terms of illustrating to colour-capable people what we colour-deficient actually see: it's not black and white, to us the world is still bright, vivid, colourful. It's our normal and that mostly isn't a problem. But a bright red rose that's colourful and vivid to me, looks to my wife grey and faded.