Infinity Alignment -- Leica vs CV

[Issy]

Anyone with a Leica body and a mix of Leica and CV lenses notice a difference in infinity alignment?

i.e. if you mount a leica lens on the leica body, and set the lens to infinity (based on scale), and look at something at a great distance, the patch is aligned.

Do the same with a CV lens (one, obviously, that rangefinder couples) --- is your patch aligned now?

Mine is not. In fact, with the CV lens (a Nokton 50), the patch indicates focus past infinity.

-- are infinity scale marks not accurate?
-- error from the the CV LTM adapter?
-- real differences in systems?

 

[Doug]

With a new lens, I would first suspect the screw-mount adaptor, some of which are not precisely the correct thickness. If you have accurate calipers, you could measure its thickness at several spots around. If you have more than one adaptor, try one of the others to see if that has an effect.

 

[Ben Z]

It could either be the adaptor or the lens itself is out of adjustment, or if you have only one other Leica lens, that one could be off. Your best way to proceed IMO is to eliminate each possiblity until you hit the right one. Try another bay adaptor, try another Leica lens. You'll get it sorted out quickly enough. I have 21 and 28mm Voitlander lenses, both rfdr coupled, both used with gen-u-ine Leitz bay adaptors, both hit infinity dead-on with all my M bodies, so it's not an incompatibility thing.

 

[Issy]

Supposed to be 0.98mm, correct?

 

[Issy]

Good call everyone. Swapped a Leica adapter for the VC adapter, and all is well (good infinity alignment).

So what does one do with a "bad" adapter (it came with the lens, so I can't really return it, and I really don't want to pass it on to someone else)?

 

[photodog]

Issy, the "bad" adapter can be easily shimmed with tape or paper to make it the correct thickness. I have read in other posts that an adapter that is too thin or too thick will still focus properly with a 50mm lens.

 

[foon]

my canon lens using on my leica with an adapter doesn't align things that are really far away
but for things like a hundred feet away it still lines up
does that really matter because I am always wondering
and i haven't done any test so far