Olympus OM-system Zuiko Reflex 500mm F8 lens. ( Catadioptric ).

An extremely compact , lightweight reflex type super telephoto lens with an exclusive Olympus lens configuration that puts the secondary mirror in front of the main refracting lens. Despite the powerful 500mm focal length it is only 97mm long  and weights 590 grams. Multicoating and special lightproof coating  of the interior surface of the lens barrel minimize flare and improve definition.  Distinctive out-of-focus ring shapes and strong telephoto effects are excellent fore special effect creative photography.

Angle of view : 5 º.

Optical construction : 5 elements in 2 groups.

Diaphragm operation : —

F-stop range : single aperture of F8

Minimum focus distance: 4 m (13.3)

Minimum field size :  19 x 28 cm. ( 7.5 x 11.0 )

Focusing : Rotating helicoids.

Weight : 590 grams  (20.8)

Length : 97 mm  ( 3.8 )

Maximum diameter : 81mm  (3.2)

Filter size ; Ø72mm.

Suitable focusing screens; 1-4 , 1-8 and 1-10. The 1-1, 1-2, 1-3 , 1-13 , and 1-14 can be used by focusing on the matte ground surface.

Notes : As a reflex type lens , this lens has no diaphragm . Exposures are set by shutter speed selections.