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This page looks at performance of the Panasonic Lumix S PRO 70-200mm f/4 OIS at 87mm on a demanding planar (flat) target at medium distance. This particular subject lays bare all lens weaknesses, but particularly micro contrast and sharpness the frame.
I shot this scene as a comparison against the Leica 90mm f/2 APO-Summicron-SL, which looked fantastic at f/2, but it exhibited a pronounced focus shift that made f/5.6 worse than f/2!
Presented at up to 93 megapixels (1.414X linear reduction from 187MP) using an approach similar to that documented in Workflow for Multi-Shot High-Res Mode Images in Adobe Camera Raw.