>Psychtoolbox>PsychTests

FitConeFundamentalsTest

This program allows exploration of how well we can fit
CIE cone fundamentals with various photopigment nomograms,
by allowing the lambdaMax to vary.

Note from DHB. My conclusion after spending some time with
this is that the best current approach, in the context of the
CIE fundamentals, is to use the StockmanSharpe nomogram and
its nominal lambdaMax values. The fit to the 2-degree CIE
fundamentals is not perfect, but it is pretty good. I think
the deviations between what is produced by the nominal
nomogram fit are probaby small compared with our certainty
about the fundamentals (this is just intuition, but for example
the deviations are small compared to those between the Stockman-Sharpe
and Smith-Pokorny fundamentals). One could try to develope a better
nomogram, for example by taking the ser/ala polymorphism explicitly
into account when fitting it, but I’m not sure that would win if one
wants to keep the convenient assumption of constant photopigment
absorbance shape along a log wavelength axis.

If one really wanted to go after fitting the fundamentals from parts,
searching on various densities as well as the lambda max values
would probably be the way to go.

8/11/11 dhb Wrote it.
8/14/11 dhb Clean up and add comments.
8/10/13 dhb A few more notes.
12/4/20 mk Add Octave support.