The Orestor and the first Pentacons (zebra design) were codenamed "Bokeh Monster" by photographers for their outstanding out-of-focus blur, which could be attributed to the 15-blade diaphragm used in these models. There are only 6 blades in the aperture of the later models, but there is no reason to complain about the quality of the blur, although the loud title remained with the 15-blade variants.
Specifications Pentacon auto 2.8 / 135
Focal length: 135mm
Aperture Limits: f / 2.8-22
Weight: 470 grams
Aperture blades: 6
MDF: 1.7 meters
Country: German Democratic Republic.
Filter diameter: 55mm
Optical design: 5 elements in 4 groups.
Ergonomics and design:
The construction and design correspond to German quality, everything is done perfectly, even the diaphragm control adapter is made for people. Pentacon auto 2.8 / 135 has an iron hood, which is very convenient for shooting. The aperture ring is stepped and has intermediate values, very conveniently located. The focusing ring travel is sufficient for precise focusing, the ring is moderately tight, rotates smoothly, without jerking or jamming, there is no looseness.
Artistic features and photo examples:
Shooting with the Pentacon auto 2.8 / 135 is a real pleasure. At an open aperture, the lens is already sharp, at closed aperture values, the picture is acceptable across the entire field, on some models you can find fault with the sharpness at open values. The Pentacon has everything in order already at 2.8: in the center without any complaints, a little softer the edges and corners of the frame. Go to f / 5.6 - sharpness from edge to edge. Very good contrast and color of the picture. There are no geometric distortions, no complaints. In contrasting areas at f / 2.8, blue chromatic aberration can be observed. Soft and pleasant bokeh, the pattern resembles Zonnar's.
The Pentacon auto 2.8 / 135 is a good quality lens: excellent sharpness, no complaints about contrast and color rendition, aperture allows you to achieve a decent and neutral background blur, everything is fine with geometry, if only the CA is slightly higher than expected and weak work in the backlight is annoying. With the Pentacon 2.8 / 135, you can replace heavy and expensive professional lenses in your arsenal and get excellent picture quality.