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Setting gamma correction using gamma grid


I have a few questions about gamma correction using psychopy (details below):

  • How do you fill the gammaGrid values correctly when you have the [a,b,k,gamma] parameters ?
  • How to you make psychopy apply this correction when presenting a stimulus ?

I have data from a spectrometer characterizing my screen, from which I computed gamma, a b, and k values for gray levels. Now I’d like psychopy to effectively use this correction.
I tried using the gamma grid by calling the methods:
monitor.setLinearizeMethod(1 or 2)
monitor.setGammaGrid(4x6 gamma grid)

But I don’t understand how I am supposed to fill the gamma grid, in case I use [a,b,k,gamma], what am I supposed to do with min and max ? Aren’t they already completely determined from the [a,b,k,gamma] values ?
Also what to do with the RGB channels if only care about the luminance ? (my stimulus is just a gray sine wave)

After calling these functions (whith a gammaGrid where I did not change the min and max), I properly see that my new matrix has been set as the gamma grid in the currentCalib. And when I use LineariseLums I also get different values :smiley:. But when I try to display a stimulus with these settings or the default ones, they look exactly the same :confused:

Any help would be greatly appreciated =)

Thanks in advance,

Bastien FB