I am using PsychPy v2022.2.5.
I used a Minolta photometer to gamma calibrate my screen. After gamma calibration this is the table that Psychopy shows:
I do not understand how after gamma calibration the background luminance of the screen is at around 90cd/m2. Can someone explain to me what exactly dictates the luminance of the background grey? Since I will use Gabor patches I want to be 100% sure that they are % michelson contrast. In addition, the background luminance should normally be around 56 cd/m2 so I do not understand why it is as bright as it is.
Help is much appreciated!