Christopher J Osborne

Olympus Pen F G.Zuiko Auto-W 20mm f/3.5 mounted on an Olympus Pen FT

Olympus Pen F G.Zuiko Auto-W 20mm f/3.5 mounted on a Sony A7 MkII

Olympus Pen F G.Zuiko Auto-W 20mm f/3.5

Cropping needed? Yes
Average 35mm equivalent focal length after cropping: 28mm

20mm f/3.5 image 1 - OOC+EC

20mm f/3.5 image 1 - Cropped
Image size: 12.3mp
35mm equivalent focal length: 28mm

20mm f/3.5 image 1 - Final
Image size: 15.4mp
35mm equivalent focal length: 25mm

20mm f/3.5 image 2 - OOC+EC

20mm f/3.5 image 2 - Cropped
Image size: 13.6mp
35mm equivalent focal length: 27mm

20mm f/3.5 image 2 - Final
Image size: 13.9mp
35mm equivalent focal length: 27mm

20mm f/3.5 image 3 - OOC+EC

20mm f/3.5 image 3 - Cropped
Image size: 13.6mp
35mm equivalent focal length: 27mm

20mm f/3.5 image 3 - Final
Image size: 12.3mp
35mm equivalent focal length: 28mm

20mm f/3.5 image 4 - OOC+EC

20mm f/3.5 image 4 - Cropped
Image size: 13.6mp
35mm equivalent focal length: 28mm

20mm f/3.5 image 4 - Final
Image size: 14.1mp
35mm equivalent focal length: 27mm

This is the widest lens Olympus made for the Pen F system. On the half-frame cameras it was designed for it has a 35mm equivalent focal length of 28mm. The edge of the imaging circle is clearly visible with this lens and cropping to exclude all but a little easily correctable vignetting did not allow any extra field of view, so the 35mm equivalent focal length of these lenses remains at 28mm. But a combination of changing the aspect ratio to 4:3 and the use of tools for the correction of converging verticals allows a slightly wider crop (often giving a 35mm equiv. focal length of 25mm). For some images I have cropped in a little further for the 'finished' version resulting in a sightly longer 35mm equiv. focal length.