Submitted by NoMoreMonkeyBrain t3_115j2j5 in askscience
Are any/all of them compound eyes? Do each pair synch up to make a separate image? Do all their eyes synch up to make a single image? Are different eyes specialized for different shapes/colors/motion?
aggasalk t1_j93o4pp wrote
This old thread answers some of your questions
https://www.reddit.com/r/askscience/comments/a0v8wy/is_a_spiders_vision_stitched_together_like_ours/
Spider eyes are simple not compound, but range in complexity (across spider species, and sometimes even within a single spider) from basic spot eyes all the way to camera-eyes something like ours.