GOZ KO-140 1:2,2 F=140mm Review
GOZ KO-140 1:2,2 F=140mm (Russian name ГОЗ КО-140 1:2,2 F=140 мм) is a cinema projection lens. Has “Petzval” optical design, which began the rapid development of portrait photography.
This copy has an aperture f/2.2 and is an earlier version. Later the lenses were made of KO-140M and 35KP-1.8/140mm with an aperture of f/1.8.
Rumor has it that the lens is a copy of Zeiss Kipronar 2.2/140mm projection lens. True it or not, there is no way to check.
The lens has an impressive size. But relatively light because the lens group is in front and behind; the middle is an empty tube. It disassembled piece by piece.
Disassembled KO-140 1:2,2 F=140mm
The “Petzval” optical design is characterized by a curvature of field, which makes a lens interesting for artistic photography. But using it requires skills.
KO-140 1:2,2 F=140mm Specs
Focal length (mm): 140
Aperture: fixed f/ 2.2
Weight (gr): about 700
Length (mm): 180
Filter Ø (mm.): none
Front barrel Ø (mm.): 64,2
Rear barrel Ø (mm.): 62,2
Resolution (center/edge): 80/45
Mounting KO-140 1:2,2 F=140mm on DSLR Camera
This lens is difficult to mount to the camera due to its huge size. The diameter of the rear barrel of 62.5 mm, so it is not easy to find such a focusing helicoid.
Is that from the mirror lens only, but it is not easy to find it for parts? An example of such a construction.
I wondered what image it gives, and I mounted it to the Nikon D3100 camera with a metal cup from the chandeliers. I wasted a rear opening a file and glued it to the back of the adapter M42-Nikon, to attach it to the camera.
The flange focal distance of the lens is approximately 65mm, allowing it to set any camera retaining infinity.
Lens to fit snugly into the cup, I wrapped it with electrical tape and took a primitive focusing mechanism of the “trombone.” This design is still viable because you need to develop a stopper, which did not allow lenses to fall out. But for a few test shots, go.
KO-140 1:2,2 F=140mm Field Test and Sample Photos
I took all photos with the camera Nikon D3100. Raw export without postprocessing.
KO-140 1:2,2 F=140mm Sharpness
The lens is very sharp in the center of the frame, but the large aperture has a narrow depth of field. At the edge of the frame, sharpness falls.
Example of sharpness at infinity
KO-140 1:2,2 F=140mm Bokeh
When particular scenes can get beautiful bokeh. “Petzval” swirly bokeh I did not find, but may not find the right background.
KO-140 1:2,2 F=140mm Contrast and Color Render
The lens has a single coating. Very afraid backlight and sidelight, because of its design. Maybe a lens hood partially saves the contrast, but I wouldn't say I like it in general.
KO-140 1:2,2 F=140mm is an interesting lens for artistic shooting, attracts the “Petzval” optical design and low price. But at the same time, it isn't easy to mount to the camera to work properly.