Adjustable patch setup

Hi, I’m trying to set up a color matching experiment.
I want to have the test surface on the screen and an adjustable patch.
Observers can press button a to make the patch lighter, button b to make the patch darker, and button c to “lock” their match and move to the next display.
Can this be done? Any ideas?
I think this is a very elementary psychophysical procedure and that it would be easy to set up, but so far I’ve had no luck…


In SuperLab 4.5 the feedback can only be based on a correct or incorrect response. However, this can be done in SuperLab 5. In SuperLab 5 you can have a different action for each key press of “a,” “b,” and “c.” The color patch would be done using a Trial Level with the Manual level selection feature.