Canon LTM lens + CV LTM-M adapter on M-mount camera

[vincentbenoit]

When I mount my Canon LTM lens onto my M6 using a CV LTM-M adapter the "symmetry axis" of the lens (as defined by the focus and aperture setting marks on the respective rings) lies about 2 cm to the left of the symmetry axis of the camera. However when mounted on an LTM camera (Bessa R) without adapter the lens is correctly aligned with respect to the camera body.

Does this mean the adapter is not suited to the lens? As things are a thicker adapter would be required for correct alignment to be achieved. Or is something wrong with the lens?

I would be very grateful to anybody who could shed light onto this issue.

Thanks

Vincent

 

[drewbarb]

This is pretty normal, and not a problem at all- your lens will work fine. If you use a lot of LTM lenses with adapters on M-mount cameras, you'll find they can line up all over the place, rarely directly "on-axis". As long as the lens is screwed all the way into the adapter and the pair is properly attached to the camera, it will focus correctly.

The only time there would be an issue is if your lens has a hood which can't be placed on axis, either because it's built-in or uses a fixed-mount (rather than a rotating mount). These can cause vignetting since they may not line up correctly.

Otherwise, you should have no problems.

 

[robbo]

I have noticed the same Vincent. I use a 50/1.4 Canon and all my test shots have come out with accurate focus, mostly shot at 1.4 too. I should add that I was using an M6TTL, it might be different on an M8/9.
I think there might be a simple fix that can be done without a visit to a technician, but I am happy to live with it.

 

[squinza]

I believe all my Canon 50mm don't align properly. Someone told me that whis way you can see the f/number set through the viewfinder.
Anyway, it's not a problem at all, they focus correctly. You just need to pay attention when you scale focus, as the reference is not at 12 o'clock....

 

[ferider]

All my Canon and Nikkor LTM lenses have done this, and I believe it's intentional. Makes you see the focus mark through the rangefinder.

Roland.

 

[John Shriver]

The infinity mark on an LTM lens normally lands at about 1 or 2 o'clock on an LTM camera, so you can see it with a large finder in the accessory shoe.

That said, if an LTM -> M adapter winds up with LTM lenses aligned significantly differently from how they land on true LTM cameras, it probably means that the start of the threads in the adapter is poorly aligned.

For some LTM lenses, if this is serious enough it can cause rangefinder coupling problems.

 

[John Elder]

Canon lens were made to align at either 1 or 2 o'clock. All of the Canon lens I have owned do that, including the 50mm 1.8 I use on my leica with a leica adapter.