“ At 18mm, central sharpness is excellent from f/2.8 to f/8, very good at f/11 and f/16 and soft at f/22. The edges are very good at f/2.8 and f/4, excellent at f/5.6 and f/8, very good at f/11, good at f/16 and soft at f/22.
At 24mm, central sharpness is excellent from f/2.8 to f/8, very good at f/11 and f/16 and soft at f/22. The edges are very good from f/2.8 to f/11, good at f/16 and soft at f/22.
At 35mm, central sharpness is excellent from f/2.8 to f/8, very good at f/11 and f/16 and soft at f/22. The edges are very good from f/2.8 to f/11, good at f/16 and soft at f/22.
At 50mm, central sharpness is excellent from f/2.8 to f/8, very good at f/11 and f/16 and soft at f/22. The edges are excellent from f/2.8 to f/5.6, very good from f/8 to f/16 and soft at f/22.
Given that the apertures available go down all the way to f/22, especially for an APS-C smaller format, means we are well into diffraction territory. This is clearly borne out by the results. At f/22 images are quite soft. However, as always, better to have the option for those circumstances where depth of field is needed more than absolute sharpness. „