FED -36 100mm f/6.3

FED FED-36 100mm f/6.3 LTM

The FED-36 100mm f/6.3 is a rare Soviet telephoto lens made for Leica-thread-mount rangefinder cameras. It was produced by FED in Kharkiv during the prewar Soviet rangefinder period and is one of the less common early long-focus lenses associated with FED and Leica-copy cameras. Sovietcams lists the FED-36 as a 100mm f/6.3 lens in M39 screw mount, with 4 elements in 2 groups, 10 aperture blades and rangefinder coupling [1].

The lens is usually encountered in chrome finish and has a compact, narrow telephoto barrel typical of early rangefinder accessory lenses. FotoUSSR lists the FED-36 with production from 1937 to 1941, weight of 228g, 1m close focus, 4 elements in 2 groups and 10 diaphragm blades [2]. These specifications place it apart from later Soviet Jupiter telephotos and from more common 135mm LTM lenses.

This entry covers the FED-made Leica L39 / LTM / M39 rangefinder version. It should not be confused with later Soviet 100mm or 135mm lenses, FED enlarging optics, Zorki-era Jupiter lenses, or non-rangefinder M39 lenses. Because prewar FED cameras and lenses may not always follow later Leica-standard tolerances perfectly, rangefinder accuracy and infinity focus should be checked on the exact camera and adapter combination [1] [3].

Optical qualities

Rendering

Reliable formal optical testing of the FED-36 is very limited. As an early f/6.3 telephoto lens with a 4 element, 2 group construction, it should be understood as a compact prewar Soviet long-focus lens rather than a fast portrait lens. Rendering claims should remain conservative unless supported by sample images from the exact copy [1] [2].

Sharpness

No reliable modern bench test was found. The slow f/6.3 maximum aperture suggests that practical use will often depend on daylight conditions, tripod use or faster film. Sharpness should be treated as copy-dependent because surviving examples may have haze, cleaning marks, decentered elements or mechanical wear [2] [4].

Contrast and coating

The FED-36 belongs to the prewar period, so many examples are likely uncoated or very early in finish by later standards. Public source data does not consistently document coating status, so the database should not claim coating unless the exact lens engraving or optical reflections confirm it.

Bokeh and transitions

The lens has 10 aperture blades according to Sovietcams and FotoUSSR, which should help keep stopped-down aperture shapes relatively rounded. Because the lens is only f/6.3, strong background separation is limited compared with faster 85mm, 90mm or 100mm rangefinder lenses [1] [2].

Digital use

The FED-36 can be adapted to Leica M bodies with a suitable L39-to-M adapter and to mirrorless digital cameras with standard adapters. However, because it is a prewar Soviet lens, mechanical compatibility should not be assumed. Infinity focus, rangefinder coupling and close-focus accuracy should be checked carefully before regular use [1] [3].

History

Development and Launch

The FED-36 belongs to the early FED rangefinder ecosystem from Kharkiv. FED produced Leica-copy cameras and lenses in the 1930s, and the FED-36 was part of the accessory-lens expansion beyond the standard FED 50mm f/3.5. FotoUSSR gives the production period as 1937 to 1941, placing it before the interruption of wartime production [2].

Production Evolution

Public information on production batches, serial ranges and version changes is limited. The lens appears as a specialized 100mm f/6.3 accessory telephoto rather than a mass-market normal lens. Sovietcams documents it as an M39 rangefinder lens with a 4/2 optical construction and 10 aperture blades [1]. Later Soviet telephotos such as the Jupiter-11 and Jupiter-9 became more familiar to users, making the FED-36 much less commonly encountered.

Special Editions/Variants

No commemorative factory special edition is documented. Collector-relevant differences are mainly condition, serial number, chrome finish, matching caps, case, engraving style and whether the lens remains in original FED / Leica-thread-mount configuration. Any conversion, replaced mount or altered rangefinder cam should be recorded as a modification rather than a factory variant.

Collector Notes

Collectors should verify the FED-36 engraving, Leica L39 / M39 screw mount, rangefinder coupling, infinity focus, serial number, aperture movement and optical condition. Important checks include haze, fungus, cleaning marks, separation, stiff focusing, uneven aperture blades and damaged threads. Because the lens is uncommon and prewar, original accessories, caps or case can add meaningful collector value [1] [2] [4].

Special editions

No confirmed factory commemorative special edition is currently documented.

Known collector-relevant variants and related versions include:

• FED-36 100mm f/6.3 LTM, chrome Leica L39 / M39 rangefinder version.
• Prewar FED-36 examples with original caps or case, collector-relevant when complete.
• Service-adjusted examples, should be documented as serviced rather than separate variants.
• Modified or adapted examples, should be recorded separately if rangefinder coupling or mount has been altered.
• Later Soviet Jupiter telephoto lenses, historically related but separate optical and production families.

Sources

• [1] Sovietcams. FED-36 100mm f/6.3. https://mikeeckman.com/sovietcams/indexb4c0.html?_m_e_id=4&_menu_i_id=77&tmpl_id=356&tmpl_into=middle
• [2] FotoUSSR. FED-36 100mm f/6.3. https://fotoussr.ru/lenses/fed-36-100mm-f63/
• [3] Wikipedia. FED camera. https://en.wikipedia.org/wiki/FED_camera
• [4] MW Classic Cameras. FED 100mm f6.3 chrome M39 screw mount lens. https://mwclassic.com/product/fed-100mm-f6-3-chrome-m39-screw-mount-lens/
• [5] Fotohandel Delfshaven. FED 5.9/100 lens for Leica screw mount. https://fotohandeldelfshaven.nl/product/fed-5-9-100-lens-for-leica-screw-mount/
• [6] Flickr. FED-36 100mm f/6.3 sample references. https://www.flickr.com/search/?text=FED-36%20100mm%20f%2F6.3