Helios 40 2 Russian 85mm M42 lens

Helios-40-2 lens history Six lens enlightened, over aperture anastigmat slightly increased compared with the normal lens focal length. Equipped with iris diaphragm and ring pre-install it. Helios-...

• Angle of view - 28 ° ',
• Focal Length - 85 mm (85.18 mm), 
• Relative aperture - 1:1,5. 
• Frame size - 24x36 mm,
• Number of lenses / groups - 6 / 4
• Front vertex focal distance - -26.85 mm
• Rear vertex focal length - 44.52 mm . 
• Distance from first to last the surface - 81.53 mm
• Light diameter of the first surface - Ø56, 9 mm;