ComputePhotopigmentBleaching - aleslab/Psychtoolbox-3-aleslab-fork GitHub Wiki

[fractionBleached] = ComputePhtopigmentBleaching(intensity,units,source)

Compute fraction of photopigment bleached, given some measure of
the intensity of light reaching the eye.

As far as I can tell, the fundemantal measurements of the half-bleach
constant for cones were made by Rushton and Henry (1968, Vision Reserch, 8, 617-631).
This fact I learned from CVRL (http://www.cvrl.org/database/text/intros/introbleaches.htm).

I am pretty sure that the Rushton and Henry measurements were made for 560 nm
light, and they give (see their Figure 2) a half-bleach constant of 4.3 log10 trolands (20,000 td).
This number is also given in Boynton and Kaiser, Human Color Vision, 2nd edition,
pp 211 and following.

It's probably fine to compute bleaching for L and M cones given retinal illuminance
in trolands, given that these are effects that matter over log10 units. But trolands
are not going to help much for the S-cones. According to CVRL there aren't good