Canon's advanced early screw rangefinder — the IVSB, Leica-thread, cloth shutter, 1952.
The Canon IVSB was a 35mm screw-mount rangefinder introduced in 1952 and was one of Canon's more advanced rangefinders of the early 1950s, with built-in flash synchronisation via a speed-selector rail. It stood among the higher models in Canon's Leica-thread line of the period.
It is a 35mm coupled-rangefinder camera taking Leica-thread lenses, with a horizontal-travel cloth focal-plane shutter reaching high top speeds for its time and a flash sync system, and no built-in meter. The combined rangefinder and viewfinder window offers switchable magnification, and the shutter is fully mechanical and battery-free.
It suits collectors and photographers who want a well-specified Leica-thread rangefinder for street, travel and documentary use. The combined multi-magnification finder and high shutter speeds made it a capable working rangefinder in its era.
Check rangefinder patch contrast and vertical alignment and confirm the finder magnification settings operate. Inspect the cloth curtains for pinholes and capping, test slow speeds and the flash-sync rail, and look for finder haze. Leica-thread lenses adapt to mirrorless via LTM adapters; verify a clean thread mount and smooth film transport.