This is also why I can't sit at the front of a theatre to watch films these days - from the middle or back of the theatre, any point on the screen is about equi

This is also why I can't sit at the front of a theatre to watch films these days - from the middle or back of the theatre, any point on the screen is about equidistant from my head, so my focus can stay fairly static. Up front (and especially a front corner) the bottom-top and center-edge of the screen is different enough in depth that if I'm trying to take in the whole canvas my eyes are working on adjusting focus basically all the time.