Rikenon 800mm f/8 (M42, preset)

The Rikenon 800mm f/8 was the longest lens Ricoh offered for its M42 screw-mount reflexes. It appears in the accessory lens lists of Ricoh’s instruction books for the Singlex TLS (1967) and TLS 401 (1970), and in the tables of the books for the SLX 500 (1975) and the Auto TLS EE (1976), both export bodies, under the heading RIKENON LENSES. The plain Rikenon name marks it as one of the few non-automatic lenses in the range, alongside the 500mm f/8, the 600mm f/8, the 60mm macro, the 135mm bellows lens and the fisheye. Both tables give the same figures: a preset diaphragm, four elements in four groups, closest focus at 18 metres, a 3° angle of view, a 112 mm filter and a weight of 2,370 g. Dr. Ricoh’s Rikenon list adds f/32 as the smallest aperture and also marks it “Preset”. None of these sources says whether it is a refractive lens or a mirror lens, and none gives a launch date, a price or a maker.

Nothing is known of versions. Neither Ricoh’s tables nor Dr. Ricoh’s list shows a differently engraved copy, a Sears-badged copy or a later revision. Ricoh moved to the Pentax K bayonet with the XR-1 and XR-2 in September 1977, and Dr. Ricoh’s list has no 800mm in K mount; its longest K-mount lens is the XR Rikenon 600mm f/8 Reflex. An 800mm f/8 with a Ricoh name and a K mount is therefore not this lens.

Because the diaphragm is a preset, the lens works the same way on every M42 Ricoh, from the Singlex TLS of 1967 and the TLS 401 to the SLX 500, Singlex II and Auto TLS EE. The aperture is chosen on one ring and closed by hand on the other just before the exposure, so the body’s automatic diaphragm plays no part. It is not an EE lens and gives no shutter-priority automation on the Auto TLS EE. That camera’s book limits full-aperture metering with ordinary screw-mount lenses to those of f/5.6 or faster, so with this f/8 lens the Auto TLS EE meters stopped down, which camera-wiki says is how the TLS 401 meters with every lens. The SLX 500’s instruction book does not say how its meter behaves with a preset lens, and nothing found describes the Singlex II with one.

A buyer should expect a heavy lens that is hard to test. At 2,370 g it needs a solid tripod, and an 18-metre closest focus makes it a lens for distant subjects only. Check that both diaphragm rings turn freely, that the preset ring stops at the chosen value and the blades close fully to it, and that the long focusing helicoid is smooth from 18 m to infinity. The front element is large, so look for haze, fungus and cleaning marks there. Ricoh gives a 112 mm filter size, and filters that large are hard to find, which matters if the lens comes without its caps or hood. The 500mm and 600mm f/8 Rikenons are its closest relatives in the range; no source found says who made the long Rikenons for Ricoh.