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Well, not really. ishihara's chart use colors that are similar or color pairs that exploit some characteristics of sensory cells in our eyes to cause errors, and this image is totally unlike that - the digits here are filled with the same color as background and the shape of a digit is formed only with a thin line of dots in a darker color (which also is common in the background). If the lines weren't so thin, we'd probably have no problems seeing these digits and this is exactly not like ishihara's tests where the colored areas are intentionally large enough to ensure one fails to see them due to colorblindness and not just due to need for some minor +/- glasses ;)

Okk @ookamisuuhaisha I think I'm wrong as you explained each detail...
Thanks for correcting me.