DA* 55mm f/1.4 on Z-1p

Images

The "Target" images used a tripod and 2-second delay and no lenshood. No filters were used.

I didn't attempt to use this lens on the Kenko 1.4x teleconverter because of concern that the largish rear element of the lens would be damaged.

I used aperture priority throughout. Being an SDM-only lens, autofocus didn't work. Even using the Pentax Magnifier FB, it was hard to focus on the rather clear screen of the Z-1p. Therefore, I only used the lens on the Target, not the Wall. I don't guarantee that I got the focusing right, although this lens was much easier to manually focus than the DA 17-70mm f/4.

Teleconverter Focal length Target  
(None) 55 f/1.4 f/2.8 f/5.6  

Discussion

I bought this as a portrait lens. I had enjoyed using the Super-Takumar f/1.9 85mm on my screw-mount 35mm Pentaxes for this purpose, and the field of view of this lens on a 1.5-crop sensor is about the same. But my home studio is rather small, and sometimes I wish this lens had a wider field of view. If it works on a Pentax FF camera it may become much more usable in this studio.

The full-aperture test shows softness, but I suspect that is because I didn't manually focus it correctly. When stopped down, it appears to behave like an FF lens, and perhaps it would even do so at full aperture with a camera that can auto-focus it.