The display contrast on my new iMac (the Retina 4k 21.5″ model) is too high. Can it be lowered past the lowest setting?

Just looking at my new iMac was giving me a headache: the “Retina” display was so high-contrast, even at the lowest contrast setting, that it was searing my retinas.

Is there a way to reduce the contrast past the lowest keyboard setting?

Can the stand in a Mid-2011 21.5″ iMac be removed?

I have a mid-2011 21.5″ iMac (EMC 2389) and I am trying to remove the stand. I’m trying to follow this guide but I can’t seem to find the “latch” that he talks about. I heard that any iMac past 2011 doesn’t have a removable stand; this is a 2011 model. Is the stand even removable (whether or not in this manner) and if so how would I go about doing it? Thanks!