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<b>Did you know you see colour differently to everyone else ?</b><br>
<b>-</b> The number, position and ratio of photoreceptors in each retina is variable.<br>
<b>-</b> The density of the cornea changes with age, generally this causes a reduction in the transmission of short wavelengths, which gives a yellow cast to the light incident on the retina.<br>
<b>-</b> Colour adaptation occurs to compensate for this, but its effectiveness is unknown.<br>
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