REVIEWS - Canon 135mm F3.5 LTM / M39

OVERVIEW

The Canon 135mm F3.5 LTM was introduced in 1952 and 8 versions were made during a 23 year production run. Optically, all 8 versions are identical. Changes were mostly cosmetic - switching from a silver barrel to black, weight reductions, wording on the front ring and the distance scale markings. Canon lens designer Jirou Mukai is credited for the 135mm F3.5’s optical formula. Peter Kitchingman’s book, “Canon M39 Rangefinder Lenses 1939-1971”, is an excellent resource which details all the rangefinder lenses and their production history.

BUILD QUALITY

As one would expect from a 1960's vintage lens, the lens is metal, with more metal and some added metal for extra measure. Add a black lacquer piano finish with some matte finish silver bits, and it is classy looking as lenses go. The lens is solid with no wobble or play, manual focus is smooth and the aperture ring clicks decisively from stop-to-stop in whole stop increments. Being a screw mount lens, a M39 to Leica M-mount adapter is needed.

HANDLING

The Canon S-Mount is the same as the Leica M39 screw mount. S-Mount lenses are often referred to as LTM’s - Leica Thread Mount. The Canon LTM lenses are focus coupled and mount on a Leica M via a standard M39 to Leica M lens adapter. I like the original Leitz adapters because they mount smoothly and I have not a problem with the adapter being too thick or too thin.

Once attached to the Leica M, the Canon LTM lenses focus via the optical rangefinder just like any other Leica M lens. The Canon 135mm LTM was produced before the days of double helicoids, so when focusing, the aperture ring rotates with the outer barrel. It is best to set the aperture first and then focus. Also, the front element rotates as the lens is focused, making polarizers tricky to use.

Another sort of "back then" feature was canting the lens ~30˚ towards the viewfinder. Supposedly this allows the photographer to see the focus distance scale via the viewfinder. In use it makes no difference, but seeing an off-center lens is a bit odd (in my opinion).

While accurately focusing a 135mm lens can be challenging, the gain in megapixels can well be worth the effort. And with the Leica M Type 240’s Live View and EVF option, focusing a 135mm lens is easy. Even with the Leica M9-P I was able to reliably focus the 135mm LTM on a consistent basis with the aide of the Leica 1.25x Magnifier.

Cropping is always an option, but the cost is very high. Leica M11 users have more cropping latitude, but going from 90mm to 200mm means ~80% of the pixels end up in the digital trash can.

PERFORMANCE

It seems good 135mm lenses are fairly easy to design. The Canon 135mm LTM can go head to head with the both the Leica 135mm F4 Tele Elmar-M and the Leica 135mm F3.4 Telyt-M APO (I own both). No fancy low dispersion glass, no ASPH elements and no APO designation - just solid performance from a simple 4 element design.

At long distances the Canon 135mm does exhibit mild halation at F3.5, but when stopped down to F5.6, sharpness and contrast are superb. Near focus performance is excellent even at F3.5. Being a 1950-1960's lens, the contrast is not quite as bold as a modern lens, but images can still pop, especially with a bit levels editing in the raw editor or Photoshop. To help ensure sharpness, if shooting handheld it is best to keep shutter speeds at 1/200th or faster. The Leica 135mm lenses have an edge in sharpness at the wider apertures. In trade, the Canon has smoother, more diffused bokeh.

CONCLUSION

If looking to add a 135mm lens for the odd 135mm shot here and there, The Canon 135mm LTM is a great way to fill the need without breaking the bank. Instead of the original clamp-on lens hood, I recommend a screw-in metal hood such as the Heliopan. The Heliopan hoods are front threaded as well, so a metal screw lens cap works very nicely.

Lastly, these are 50 year old lenses, so a CLA may be in order - though, neither of mine needed CLA. If trying to buy a "newer" Canon 135mm LTM, serials numbers 105,000+ are among the last ones.