Canon LTM issue with Leica iiif

[justintrigue]

Hi Forum,

I love my Leica iiif and recently picked up a Canon 35mm f1.8 ltm to complement my existing Leica ltm collection. However, in the first shots with the Canon, I noticed what appeared to be a front-focusing issue - the foreground tends to be more in focus than what the rangefinder indicates. The rangefinder works great with all of my Leica branded glass, so I'm wondering if there's something about the Canon that is throwing the rangefinder's focus off. It seats properly on the body, but when focussing at infinity in the viewfinder, the lens indicates a focussing range of more like 10 ft. If I set focus on the lens to its infinity marking, the rangefinder looks completely off. I just shot a diagnostic roll to see which is accurate, the rangefinder or the lens markings, but can anyone shed some light on this for me? Should the canon naturally work with the iiif's rangefinder? Does this describe a technical issue with the lens itself?

Thanks a bunch for any guidance.

-Justin

:bang:

 

[charjohncarter]

Not quit answer for you but I have a Canon Serenar 35mm f 3.5 that is focus accurate on my IIIf. I also have a CS 100m that is focus accurate.

 

[oltimer]

I suspect you have a lens that has been taken apart, but not reassembled properly. I have that Canon lens plus the 50/1.2, 50/1.4, and the 50/1.8; and all work perfectly (rangefinder correct) on my Midland 3F, and Canon 7sz and VT. In most cases the lens sitting around for 50 plus years would have dried out grease, and very stiff to use; that is why I stated someone was into that lens.

 

[Luddite Frank]

I have a Canon 35mm / f:1.8 LTM and have never gotten what I feel are "sharp" images out of it. 😡

I have used it on my 1934 III, and my pristine 1949 IIIc.

I feel that I get consistently sharper images from my 1940 uncoated Elmar 35. 😕


Perhaps my example needs to be serviced, but I believe I have read commentary that the 35 / 1.8 was not Canon's "best" 35mm lens ?

 

[zauhar]

I likewise recently got that lens, have not had focussing issues on IIIg , so I have to support the suggestion its a lens problem.

Randy

 

[colyn]

With all of the people today who thinks they can repair their own equipment, I suspect someone may have taken the lens apart to clean it and did not reassemble it correctly.

I would return it for a full refund...

 

[David Murphy]

The Canon 35/1.8 will make quite sharp images, especially at mid aperture settings. It's a fine and fundamentally modern lens in the context of what it is (when it was made, cost etc.). I owned one at one time and found it a pleasure to use.

I agree with the above posts that the lens likely has maintenance issues. Any experienced technician can help you trouble shoot that. Adjusting the rangefinder cam is an not-uncommon LTM lens repair for instance, although the problem may be something more complex (such as lens elements reversed, missing, or seated incorrectly). You might try DAG camera - if he can't fix it (and he probably can), it's unlikely anyone else can!

 

[Robert Lai]

Does your lens still have the original Canon rear cap on it?

My 50mm 1.4 LTM had the original cap. What happened with mine was that the OEM cap is too shallow. If you turn the focus ring anywhere off infinity with the cap on, you WILL ruin the focusing accuracy as the RF cam will ram up against the inside of the rear cap.

I had the lens adjusted along with a CLA of my Canon 7s. Now that lens is super accurate in focusing at 1 m at f/1.4.

Send your lens in for repair - it's worth it.
Toss the rear cap if it is too shallow.

 

[justintrigue]

Thanks for the various stories everybody. Really helpful in diagnosing the problem.

I do believe the original rear cap came with it. It was purchased from a Japanese reseller who is willing to accept a return - just unfortunate because I had heard this lens performs great on the iii series. The lens is in excellent condition otherwise, so maybe I'll try to find a tech close by in South Florida who can do a true assessment of the situation before I return it.

Thanks again! Amazing to get all this user guidance in such short time!

 

[justintrigue]

For others with similar problems - I've now spoken to a few repair professionals and the issue seems to be how the rangefinder flange is seating with the Canon. The lens is seating on the body properly, but it's pushing the flange too far back and as a result, the rangefinder is thrown off by overshooting the actual lens focussing distance. I think this lens is destined for a return.

 

[colyn]

I think this lens is destined for a return.

Sounds like a good idea. This is most likely caused by a poor quality repair job...

 

[nhchen]

For others with similar problems - I've now spoken to a few repair professionals and the issue seems to be how the rangefinder flange is seating with the Canon. The lens is seating on the body properly, but it's pushing the flange too far back and as a result, the rangefinder is thrown off by overshooting the actual lens focussing distance. I think this lens is destined for a return.

A few years ago I bought a completely seized one to try and repair. When I took it apart to relube the helical, I installed it back on the wrong starting thread and got the same problem as you. I just took me a few goes to find the correct thread for the helical to go in and now everything works as it should. There weren't too many combinations to check for the right one so it didn't take me too long.

regards,
nathan