The edges are excellent from f/1.7 to f/4, very good from f/5.6 to f/8 and good from f/11 to f/16. At 25mm, central sharpness is outstanding from f/1.7 to f/4, excellent at f/5.6 and f/8 ...

At 25mm, central sharpness is excellent at f/1.7, outstanding from f/2 to f/5.6, excellent at f/8 and still very good at f/11 and f/16. The edges are very good from f/1.7 right through to f/8 and ...