The Mamiya-Sekor 55 mm f/ 2.8 C is a good fast lens. When wide open, the image is blurred. This effect is corrected by stepping down. From f/5.6 onwards the lens performance is acceptable, and at f/11 it is excellent. Slight vignetting notable at open apertures vanishes at f/5.6.
Accordingly, we will further deal with the lens performance starting from f/8 onwards. The lens sharpness at low frequencies causes no surprise even when mounted on the PhaseOne P65+; on digital backs with worse resolution there are no problems, either.
However, the Mamiya-Sekor 55 mm f/ 2.8 C resolution (high frequencies operation) is moderate. In other words, the lens renders individuals items perfectly well, but fails to render image texture. On this account it is not suitable for landscape photography: a detached fir tree is rendered fairly well, whereas tree branches are blurred. Nevertheless, the lens may be quite suitable for streetscape photography.
Corner distortion is negligible.
The substantial drawback of the Mamiya-Sekor 55 mm f/ 2.8 C lens - even on modern cameras it does not provide information on aperture values. As a result, exposure values and focusing are manually set, and it may take rather long to take a single picture. It is very inconvenient to use the lens in a crowd, though its optical characteristics allow to.
Its younger brother, Mamiya-Sekor 55m f2.8 N, differs in a greater number of coatings.
Posted by: semenyaka Date of publication: 06.04.2011