Canon M39 Rangefinder 35mm f:1.8

Doesn't replace the Summicron 35 f2, but still useful

The Canon 35 f1.8 is one of those half-black "transitional" lenses of the mid 1960's - part way between the fully chrome lenses and the final run of mostly-black designs of the Canon FL/FD time frame. I thought I'd give it a try as a possible low-cost user alternative to the pre-aspheric Summicron 35mm. Most of my use with this lens has been wide open, at f 1.8.

Bokeh

Let's face it: One of the primary reasons to use Leica rangefinders is the ability to shoot at fast apertures and render nice selective focus. In this image, cheap 400 speed film is exposed at f1.8. Right away we see the qualities of boke (out of focus details). With this Canon rangefinder 35mm lens, the fuzzy highlights are soft, smooth, but slightly "football" shaped (I'm in the USA where a football isn't round). In practice the non-round highlights are only an issue where they're really in high contrast, and generally not a problem. The lens has 9 blades in the iris to help smooth out the blurred details. The non-round shapes are oriented as tangents around the center of the frame, with the shapes tending toward correct circles as they approach the image center.

Full frame, Canon rangefinder 35mm f1.8, wide open on 400 ASA film

Detail, Canon rangefinder 35mm bokeh. Note the slight "football" shaping

Sharpness

The Canon lens doesn't quite have the same ruthlessly sharp performance wide open as the pre-asph Summicron 35, but still it is decent and makes it a great user lens. This detail is near full resolution (scanned at 4000 DPI on a Nikon Coolscan 4000ED, using the modified SA-21 / SA-30 roll feeder on C41 color negative film).

Handling

The lens supports decent images but has weak points in usability. Focusing goes down to 1 meter, while the Summicron will go down further, to 70 cm.

The focus ring turns about 180 degrees from infinity to 1 m, making the close-focus position of the infinity lock almost up to where the camera's viewfinder is (on Leica M bodies). This is a drawback, it's too far to turn the ring in practical use.

Conclusion

I'm not sure if the Canon 35mm f1.8 is a user or collector lens. The performance and price put it in the user category, but the close-focusing quirks and strange 40mm filter thread are usability drawbacks. I'll hold onto this one for a while though, I still like it.