Panasonic 25mm f1.7: Vignetting

for further subjects, the lens would often miss focus, always to the front, causing some shots near infinity to appear soft, even when stopped down..

Vignetting , however, while low at -1.4 EV (maximum), is actually quite noticeable.

very noticeable at the fastest apertures, so much that the entire image appears darker at f/1.7, but it all but disappears by f/4.