Specification of LOMO OKS5-750-1 optical block

The OKS5-750-1 lens is purposed for usual film shots.

Manufacturer   NPO "EKRAN"
Lens system   -
Focal length
f' 750.0 mm
Angle of view 2ω' 2°05'
Effective relative aperture f:nэ 1:9.9
Lens length Σd 478 mm
Front focal length S -
Back focal length S' 36.1 mm
Flange focal distance Z -
Block length B 490 mm
Block max. diameter D 142 mm
Rear diameter D' -
Front element diameter d1 94.0 mm
Rear element diameter d2 28.0 mm
Mount thread   -
Distance from rear end of the housing
to the focal plane
l -
Aperture blades quantity   ?
Frame size   16x22 mm
Weight   4.8 kg