This is a painting by Leng Jun. Considered to be the most realistic painting. See

Renaissance artists would have been supremely amazed by the detail. Granted they didn't have photography that would have allowed them to get better notes (or the pigment chemistry science to get better paints but that's another thing already). Though i don't know this painter maybe he didn't use photographs which would be even more impressive. Actually, this reminds me of of Daguerreotypes and how one french painter said something along the lines that there wasn't a need for artists anymore because a photograph could capture an event perfectly. This artist mastered his technical skill to match that of a photograph which to me is just amazing.