[tgbugs]

Minor factual correction. Octopuses are not color blind, they only have a single photo receptor opsin but likely reconstruct color using chromatic aberration in combination with diffraction caused by their pupil shape to infer spectral properties of light (i.e. color). https://doi.org/10.1073/pnas.1524578113

[neom]

Wild, thanks for sharing. My degree is in digital imaging and I spent years battling CA, interesting to imagine that something uses it to see colour, wonder what it would look like. Continuous spectral differentiation via CA vs "bins" of color from separate photoreceptor types, I'd guess they might be capable of seeing subtle spectral nuances differently or even more sensitively in certain conditions than traditional multichannel systems like ours...also from this paper it seems the SA is extremely well corrected, if the lens GRIN is perfectly tuned radially to correct SA at one wavelength (say green @ 550), the radial profile that minimizes SA at one wavelength likely misalign SA correction at another wavelength. It seems this SA/CA system would produce a very unique multidimensional preception of space + a super unique colour gamut?