This lensThe Canon 50mm f/1.8 referred to here is a Type 1 and is thus an all chrome rangefinder lens, produced by Canon to fit Leica Thread Mount, 39mm, lens mount cameras. This lens was designed by one of Canon’s legendary designers, Hiroshi Ito. Manufacturing of this lens was during the 1950s. It is a double-gaussian design, which just for interest, is also the basis for the famous Zeiss Biotar which then led to the Planar. It is constructed with six elements in four groups.
It is a very compact lens designed for Canon’s original rangefinder series of cameras, and was based on the post WW2 Serenar lens designs manufactured by the Canon company. I believe the pristine model I purchased was manufactured in the late 50s.
The aperture range is from f/1.8 through to f/16. Aperture is controlled by a ring towards the front of the lens, which clicks into stops. Ten aperture blades are used on this lens.
- Marketed November 1951
- Original Price 26,000 yen
- Lens Construction (group) 4
- Lens Construction (element) 6
- No. of Diaphragm Blades 10
- Minimum Aperture 16
- Closest Focusing Distance (m) 1
- Filter Diameter (mm) 40
- Maximum Diameter x Length (mm) 48 x 36.8
- Weight (g) 270
A famous standard lens in the modern optics history, which succeeded in eliminating flare caused by coma, a drawback of Gauss type lenses. Based on the optical theory developed by this lens design, various high performance wide angle and telephoto lenses with large apertures were developed.
SummaryThe lens may not have the f/1.4 maximum aperture that many prefer, but I have to say given the quality of digital sensors these days, the fraction of a stop difference between f/1.4 and F1.8 is not that big a deal for me. The lens is very easy to handle, and aperture detents are pretty solid. The only limitations I have had to adjust to are the pretty long focus throw from minimum distance to infinity, plus the minimum focusing distance of about 3 feet, which is standard for a rangefinder lens.