ISCO-Göttingen Tele-Westanar 135mm f3.5

[SXR_Mark]

This lens is in Praktina mount and is tested on my Oly OM-D E-M5.

The lens is quite compact and has a decently short minimum focusing distance of 1.3 m. It has (I think) 15 iris blades. It is a bit of a pain to use as the aperture ring is at the front of the lens and rotates with the focus and it is therefore not possible to change the aperture without changing the focus. A stiffer focus and softer aperture clicks would help.

Wide open, the lens shows good, though not biting sharpness. It can show both green and red fringing, as can be seen in the crop of the Welsh Poppy shot below.

The test shots below were all taken wide-open at f3.5 except the last one which was at f5.6. PP is limited to general curves adjustment to boost contrast and cropping for composition. Contrast and colours from the lens are pretty good straight from the camera, but there is almost no lens that does not benefit from a curves tweak.













This crop of the above shot shows the green and red fringing. You can also see the sharpness is good but not great.

[SXR_Mark]

Below are pictures of the lens on the E-M5. The Praktina to m4/3 adapter is my own creation.