Sharpness at 45mm

For this test, the Fujinon XC 15-45mm f/3.5-5.6 OIS PZ lens was attached to a Fuji X-A5 body, which in turn was mounted on a sturdy tripod. Exposure delay mode was activated and focus is set to the middle of the frame. Tonal and colour variances across the crops are due to changes in natural light during the session.

The full frame at 45mm

At the telephoto setting the widest aperture is f/5.6, while minimum aperture remains at f/22. Centre sharpness is again very good at all apertures. 

Looking really closely we would say f/11 has the edge over the other apertures, but there is little to choose between them all, save for the slightly softer f/22 aperture. Corner detail at 45mm is largely maintained from the centre.  

Aperture	Centre Crop	Edge Crop
f/5.6
f/8
f/11
f/16
f/22