Ricoh's TLS 401 — mechanical M42 SLR with switchable eye/waist-level finder, 1970.
The Ricoh TLS 401 is a 35mm film SLR made by Ricoh and introduced in 1970 using the M42 screw mount. It is unusual for offering a switchable viewfinder that allows both eye-level and waist-level viewing, a feature not common on screw-mount SLRs. It was a mid-range enthusiast body.
It is a single-lens reflex for 35mm film using the M42 screw thread. The TLS 401 has a metal focal-plane shutter with a top speed of 1/1000 second plus Bulb, and through-the-lens CdS metering for manual, match-needle exposure. Its distinctive feature is a finder selector that switches the view between eye-level and top-down waist-level viewing. The shutter is mechanically timed and fires without a battery, with the cell powering only the meter.
The TLS 401 suits general, student, street and landscape photographers who value the flexible dual-view finder and the wide M42 lens pool. The switchable viewfinder makes low-angle and copy work easier than on a fixed-finder body. Its strengths are the finder flexibility and lens compatibility; its limits are weight and the basic match-needle metering.
When buying used, check the foam light seals and mirror-damper foam, which perish with age, and confirm the finder switch mechanism works smoothly. Test the mechanical shutter across its speeds for capping or slow-speed lag, verify advance and rewind, and check the meter needle. The meter was designed for 1.35V mercury cells (PX625/625 type), so recalculate exposure with modern cells; the mechanical shutter still fires with a dead battery. M42 lenses screw on and adapt widely.