>>3785504Sharper, better contrast, livelier color. The 1.8 isn't so bad from f4 but mine (circa 08 or 09) has never been that impressive. Flat colors, low contrast, and the build quality is terrible. It creaks and flexes when handled. After just a couple years the mechanical aperture ring gummed up and the housing feels like dollar store plastic.
I picked up the f2 for dirt cheap based on Bjorn Rorslett's glowing review. I definitely think it's a bit of a sleeper in the AI world.