I see no number either and I know my colour vision is ok - I have a known very slight perceptual diff between my eyes due to a childhood infection of the optic nerve. One eye, other eye, both -still nothing. B struck me as in and C out because I nomally get light from above so this is the way my brain expects to see it. I can however, tell it otherwise and can make them go the otherway around. Hope that helps.

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