CJ,
As I understand it, the original CIE studies presumed that colour sensitivity was a function of the fovea and was based on a 2° target area. It was later realised that blue sensitivity was under represented due to the extrafoveal distribution of s-cones. I think the Judd Voss modification was based on a 10° target area.
I'm not sure I understand all the details of the Sharpe et al modification. It appears to recognise the serine/alanine 180 sensitivity variation I mentioned before, but there are other experimental features I don't understand.
David
P.S. Obviously these studies produce averages which have their practical value, but they also mask the range of individual variation. Some years ago I was working with a colleague on an imaging system which required both short and long wavelength illumination. Using 780nm LED I could see well enough to get around the lab, but my colleague saw nothing at all beyond about 720nM. We could both see 385nm LEDs but he saw them as blue whereas I saw them as violet. I've found both these functional differences acknowledged in the scientific literature, but as yet, unexplained. There are a lot more wrinkles to this story that have yet to be ironed out.
P.P.S. Another feature of the more recent studies was that they included women.:-O :t:
As I understand it, the original CIE studies presumed that colour sensitivity was a function of the fovea and was based on a 2° target area. It was later realised that blue sensitivity was under represented due to the extrafoveal distribution of s-cones. I think the Judd Voss modification was based on a 10° target area.
I'm not sure I understand all the details of the Sharpe et al modification. It appears to recognise the serine/alanine 180 sensitivity variation I mentioned before, but there are other experimental features I don't understand.
David
P.S. Obviously these studies produce averages which have their practical value, but they also mask the range of individual variation. Some years ago I was working with a colleague on an imaging system which required both short and long wavelength illumination. Using 780nm LED I could see well enough to get around the lab, but my colleague saw nothing at all beyond about 720nM. We could both see 385nm LEDs but he saw them as blue whereas I saw them as violet. I've found both these functional differences acknowledged in the scientific literature, but as yet, unexplained. There are a lot more wrinkles to this story that have yet to be ironed out.
P.P.S. Another feature of the more recent studies was that they included women.:-O :t:
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