LTM adapters and infinity locks - help!

Matthew Allen

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As the keen eyed amongst you may have gathered, I'm looking to buy a 50mm LTM to M adapter. I have one concern though, which is the issue of infinity locks.

The lenses I need the adapter for (Summar and Summitar) both have infinity locks and having researched this a bit it seems that non-Leitz adapters may not allow focusing all the way to infinity because the infinity lock gets in the way. So:

1. Can someone confirm that this is indeed the case? I'd love to be able to use a cheap heavystar adapter or something rather than a ($$$) Leitz one but mutilating my lenses is not an option.

2. If not Leitz, is there someone out there making clones of the Leitz adapters?

Cheers,
Matthew
 
Matthew, I came to your university for a seminar back in 1976 or so and sampled several whiskies in the town. More to the point, the two adapters I have from www.fedka.com have the same shape as my Leitz adapter: some of the outer circumference is cut away to accommodate the infinity lock. I don't know about the CV ones.
 
Dear Matthew,

Mutilate the adapter instead, in the unlikely event that you have to: Dremel out a crescent to accommodate the infinity lock.

Cheers,

R.
 
I use a Summitar in a Voigtländer adaptor and haven't encountered any issues at all. The Voigtländer adaptors are readily available and are really nicely made.
 
Matthew, I came to your university for a seminar back in 1976 or so and sampled several whiskies in the town. More to the point, the two adapters I have from www.fedka.com have the same shape as my Leitz adapter: some of the outer circumference is cut away to accommodate the infinity lock. I don't know about the CV ones.

Thanks Payasam, Fedka looks to be a possiblity. Have you specifically tried a Summar or Summitar in it?

Dear Matthew,

Mutilate the adapter instead, in the unlikely event that you have to: Dremel out a crescent to accommodate the infinity lock.

Cheers,

R.

I'll certainly consider that. I'm not sure though how much material one would have to remove, and if indeed if the modification is practical. Also, these adapters are amazingly expensive so it'd be nice to get one that I wouldn't have to attack with a Dremel right out of the box.

I use a Summitar in a Voigtländer adaptor and haven't encountered any issues at all. The Voigtländer adaptors are readily available and are really nicely made.

Interesting, which version (I or II) of the adapter do you have? I ask because our bartender's site says quite explicitly:

TYPE II $55 Introduced Sept 2007. Wide Rim like the original Leitz Adapters. Not usable for Leitz 35mm or 50mm lenses WITH infinity locks.

http://www.cameraquest.com/adaptltm.htm

I'd welcome more comments about this, and also any pictures that actually demonstrate the problem in question. I'm rather unclear about precisely which bit of the adapter gets in the way.


Cheers,
Matthew
 
note on FSU lenses and Leitz adapters

note on FSU lenses and Leitz adapters

I have an I-22, and an I-50 that don't quite allow for the infinity lock to engage with the Leitz cutout adapters. They miss the locking groove cutout on the adapter by about .25mm or so.

However, they still take great photos at the near infinity position, so I haven't bothered modifying either lens or adapters.
 
I guess my CV adapters are of the type I design. There's a good 3mm of clearance between the infinity lock on the Summitar and the adaptor. I can't guarantee that all Summitars have identical infinity lock designs, but I don't see any way that this lens would have an issue with any L39-M adapter.
 
I no longer have a Summitar, Matthew, nor any screw lens with an infinity lock. However, the Fedka adapters match my Leitz adapter precisely when put together face to face.

You might like to write to mail@fedka.com: Yuri's friendly and accommodating. Mind that his adapters cost only marginally less than the CV ones.
 
My early Summitar works fine with a CV (type I) adapter - and I think it really should work with any adapter, because the infinity lock is well clear of the camera body/adapter.
 
The only lens that might have interference with the adapter are those with locks flat with the lens mount surface, lens like Summar or the Summitar has the lock elevated so there is no problem. The only I know of is the Elmar 50/3.5 and its copies
 
The only lens that might have interference with the adapter are those with locks flat with the lens mount surface, lens like Summar or the Summitar has the lock elevated so there is no problem. The only I know of is the Elmar 50/3.5 and its copies

Exactly what Hans said, with the addition of the Elmar 3.5cm/3.5 (and I suppose, with no direct experience, the Hektor 2.8cm (is it 6.3?) and the Hektor 5cm/2.5, which also sports similar mounts).
 
From looking again at my lenses I think you are all quite right. It doesn't look like they could interfere with any adapter. Now I just have to choose one, having just lost an ebay auction for a real Leitz IRZOO. Curses - outbid by less than $2.

Matthew
 
I have never had infinity lock issues with adapters per se. But other users should be aware that I have had infinity lock issues with some older lenses on a more modern M body. Specifically I have found that on some lenses the infinity lock can foul the frame selector lever on my M4P. This is most problematic with a 35mm f3.5 Summaron. (This is the early bayonet mount Summaron designed for use with the M3 and a separate shoe mounted finder.) I suspect other wide angle lenses with a focus lock may have the same issue (The problem is the height of the focus lock above the base of the lens - there is just not enough clearance for it to swing over the top of the level.)
 
Here's a photo of three Leitz adapters I have... Only the left one with cut out area works on my 35mm Summaron and allows infinity focus.

If you're handy with tools, modification should be easy.

Glenn
 

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Here's a photo of three Leitz adapters I have... Only the left one with cut out area works on my 35mm Summaron and allows infinity focus.

If you're handy with tools, modification should be easy.

Glenn

Thanks, that makes it quite clear.

It looks like I won't need to do any modification as I've found a Leitz IRZOO in the UK for £22. Leitz's 5 letter codes make it surprisingly easy to find stuff sometimes.

Matthew
 
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