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Grating changed appearance after gamma correction

Hello,

I am using gratingstim to create sin grayscale drifting gradients of various orientations. I recently gamma corrected the monitor (see attached graph) by custom script and noticed tha grating changed appearance. In particular, the black bars seem to become narrow, while white bars wider. I cant really attach the screen shot because it will look normal (sinusoidal) on different monitor.

Does anybody experienced this? Is it normal for gratings to change after gamma correction?

I would appreciate any help on this.

Thanks,
t

Yes that is exactly what you would expect from successful gamma correction. The mid-greys are brighter on a corrected monitor to undo the effects of the curve you posted, and that means the bright bars will look wider.

Thank you very much, now it makes sense.