Christopher J Osborne

Olympus Pen F E.Zuiko Auto-W 25mm f/4 mounted on an Olympus Pen FT

Olympus Pen F E.Zuiko Auto-W 25mm f/4 mounted on a Sony A7 MkII

Olympus Pen F E.Zuiko Auto-W 25mm f/4

Cropping needed? No

25mm f/4 image 1 - OOC+EC

25mm f/4 image 1 - Cropped
Image size: 24mp
35mm equivalent focal length: 25mm

25mm f/4 image 1 - Final
Image size: 24mp
35mm equivalent focal length: 25mm

25mm f/4 image 2 - OOC+EC

25mm f/4 image 2 - Cropped
Image size: 24mp
35mm equivalent focal length: 25mm

25mm f/4 image 2 - Final
Image size: 24mp
35mm equivalent focal length: 25mm

25mm f/4 image 3 - OOC+EC

25mm f/4 image 3 - Cropped
Image size: 24mp
35mm equivalent focal length: 25mm

25mm f/4 image 3 - Final
Image size: 18.6mp
35mm equivalent focal length: 29mm

25mm f/4 image 4 - OOC+EC

25mm f/4 image 4 - Cropped
Image size: 19.1mp
35mm equivalent focal length: 28mm

25mm f/4 image 4 - Final
Image size: 18.8mp
35mm equivalent focal length: 29mm

The 25mm f/4 was the least expensive wide-angle lens for the Pen F system. It would have formed a standard set along with the 38mm f/1.8 standard lens and 100mm f/3.5 telephone lens for many Pen F owners. On the half-frame cameras it was designed for it has a 35mm equivalent focal length of 35mm.

As you can see from the OOC+EC images this lens has a much larger imaging circle than the 20mm f/3.5 above. In fact, if vignetting is your only concern then cropping is rarely needed at all, resulting in a slightly wider field of view than the shorter focal length 20mm f/3.5 above. But there is a gotcha! Although there isn't much vignetting outside of the half-frame imaging area, there is a huge drop in sharpness in the corners which many people would still want to crop out. But find this complete lack of sharpness in the corners give a distinctive quality to the photographs (almost like a very mild 'lensbaby' effect) that I quite like, and many of the 'cropped' versions with this lens have just had the vignetting corrected.