Johannes Vermeer's "Girl with a Pearl Earring" 1665) - "Certainly the way Vermeer captured subtle changes of light and focus seems to anticipate photography: some features appear in focus, while others seem out of focus, and objects are depicted with a foreshortening that resembles that seen in photographs -- this is perhaps one reason why he appeals to us today."
Several sketches have been drawn by Leonardo Da Vinci that lead to a final painting, the Virgin and the Child with St. Anne. On this sketch of possibly St. Mary, Leonardo employed Sfumato (a technique to apply smoke for forms rather than edges to separate light and shadow). There’s no edge. It should disappear by blending same tone throughout. This also shows the master’s methodology of keeping his sketches in notes way before he was given a commission to work on a big project
Jan van Eyck's "The Arnolfini Portrait" (1434) "From the fabrics and the fur trimming of the clothes to the wooden window frame and the bull's eye windowpanes -- everything is depicted using a degree of detailed realism that makes objects seem almost tangible."