LOMO OKS7-28-1 (2/28mm)

The OKS7-28-1 lens has extended back focal length of 32 mm. Optical construction is complex system consisting of 9 elements grouped into 7 components. Image quality corresponds to early OKS4-28-1 lens, bat OKS7-28-1 lens has longer back focal length.

Specification of LOMO OKS7-28-1 optical block
Lens system

Focal length
f' 28.0 mm
Angle of view 2ω' 51°50'
Effective relative aperture f:nэ 1:2.3
Lens length
Σd 43.3 mm
Front focal length S -
Back focal length S' 31.5 mm
Flange focal distance Z
41 mm
Block length
B 45 mm
Block max. diameter
D 45 mm
Rear diameter
D' SpM 33x0.75
Front element diameter
d1 31 mm
Rear element diameter
18.5 mm
Mount thread

SpM33x0.75 cl 2a
Distance from rear end of the housing
to the focal plane
32.5 mm
Aperture blades quantity

12 ?
Frame size

16x22 mm
130 g