I have been working on creating a custom cone-catch model for my system and I believe it has been pretty successful. However, when converting the cone-catch to an RNL chromaticity and measuring the mean X and Y values, I have only been able to get a mean X value. I believe that the lizard model I used is a trichromat but I thought it was still possible to get both an X and Y mean. In order to try and solve this issue, I added a luminance channel through the LW channel (based on the literature of my system, a lizard) and then was able to get both the X and Y means. I just wanted to double-check that this was a valid way to get that Y mean value. If I was interested in then measuring luminance, could I just use that Y mean as the luminance channel for the pattern and luminance measurement?
Thank you so much for all the help and for the great program!
Please note that a visual system with n cone channels will have n-1 opponent channels as per the RNL model in it’s chromatic (original) form. Therefore, your model needs to produce both, an X and a Y opponent channel. If it doesn’t, then you might have an error in your visual model files (e.g. wrong order or naming of channels). Please also note that the luminance channel is processed separate for chromatic (traditional RNL model using all cone channels) and achromatic contrast (using the achromatic adaptation of the RNL model as per Siddiqi et al.). I hope this clarifies it. The easiest way to make sure the files are setup correctly is by using already functional trichromat files in the toolbox and substitute the values with those of your new system. That way you can be sure that formatting, naming etc. are likely without error.