I am wondering if you have this happening on your 83+ models? I mean when checkered patterns are displayed through almost an entire pixel column (most grayscale routines count, as they're checkered patterns or scanlines moving really quick most of the time) this column contrast gets lighter. In case the entire column is a checkered pattern it gets light to the point where even at max contrast it still shows as light as if your contrast was at default settings. It does that with horizontal lines too. Seems like old 83+ LCDs aren't that much better than 83+SE/84+ after all

Note, this is not the calc that has a problem, because my older 83+ (the one with the Omnimaga logos on it) does that too and I tried with many student calcs at school and all 83+s would do this. I never tried with a 82 though and neither with a 83 because this model is super rare where I live compared to the 82 and 83+

EDIT: Btw yes this is a robowar screenshot. I was testing a grayscale routine by tr1p1ea when I took that pic

EDIT 2: Reuben looks even worse. I noticed this ever since I started coding calcs but I only talked vaguely about it before because I didn't have a good camera to show it

Yeah same here, except with Reuben Quest of course (since grayscale with Omnicalc isn't very fast). However I have this happen even with brand new duracell batteries

You got it to happen on SE too? For me it slightly happened, but it was barely noticeable at all compared to the regular