LTM to M adapter

[Ramersdorfer]

I assume Acliff means that the lens rotates 2cm too far or not far enough when being mounted so that the focusing index is not dead centre at the top. Is this correct? This is what happens with my 50mm Nokton mounted on my M2 with an original Leitz adapter, although in my case its only a few mm. From what Rob-F said about the adapter flange not being wide enough, you seem to be thinking of lateral displacement of 2cm.
I haven´t yet noticed a problem in the end result with my set up.

 

[Acliff]

I assume Acliff means that the lens rotates 2cm too far or not far enough when being mounted so that the focusing index is not dead centre at the top. Is this correct? This is what happens with my 50mm Nokton mounted on my M2 with an original Leitz adapter, although in my case its only a few mm. From what Rob-F said about the adapter flange not being wide enough, you seem to be thinking of lateral displacement of 2cm.
I haven´t yet noticed a problem in the end result with my set up.

Yeah, I think I was mixing up two different problems. The leitz adapter is bang on centred, no issues with bring up the right framelines and such. The lens when screwed on is rotated by about 7-8mm too far. I was thinking that I might be overtightening it, but any less and I would risk the lens falling off.

I'm not very experienced with screw mount lenses, and I was concerned about the adapter considering the m mount 35mm skopar that I have is obviously just right.

 

[Rayt]

I understand the Leitz adapters are designed so the lens screw in a few mm beyond the center point. Not sure why that is.

 

[mad_boy]

I see two possible technical reasons a lens can be off center.

1) incorrect flange thickness.
As mentioned in earlier post, the thickness of the flange is very tight. The M bodies are 1mm thinner than TLM bodies, and hence the 'ideal' measure of the flange is 1,00mm. It seems Leitz made them to a range of 0,98 to 0,99mm assuming there is always a little dirt on the flange.
If the thickness of the flange is for example 0,95mm then one can screw the lens further in; in other words it will go past the normal point.
The diameter of the lens is app. 15 cm and the pitch of the thread seems to be 1mm per rotation, so every 0,01mm flange deviation will give 1,5 mm off-set of the lens. i.e. a correct one should be between 0 and 3mm off.

2) the position of the thread with regards to the 0-point of the adapter is off. In other words the flange is rotated with regards to the screw.

Both of these are manufacturing defects. The 1st one will lead to focussing problems (apart when on a 50mm lens) especially for wide angle lenses.

Do check the thickness of the flange using a quality digital caliper.
If it is more than 1mm you could try to correct; but this is tricky.
If it is less than 1mm bin it or use it on a 50mm...

mad_boy

 

[Svitantti]

Roxsen's filters are off too, also I bought a second from eBay that looked different, but was even more off 😀.

Should just get a Leitz or Voigtländer I guess.

 

[marknyc]

Got mine from Steve and cameraquest and it is perfect

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

 

[Acliff]

I've attached a photo of what my 1.5 nokton looks like on my m2.
Using a genuine Leica adapter.
Is this a normal amount of rotation?

 

[former member]

The Rotation, some lenses where made to rotate closer to the viewfinder, others straight up. "Normal" on an adapter should be the same that it does on an LTM camera.

But...
It will not make a difference in the actual focus agreeing with the RF.

Make sure the lens focuses correctly to infinity. At that pint, the distance scale, RF, and actual focus should all be good.

 

[Carlsen Highway]

I bought a Roxsen brand adapter (pretty sure the same product as Pixco) from a shop in Hong Kong on Ebay...it works perfectly fine with my Jupiter 8 and M2.

I measured it with micrometre calipers when I got it and it measures thickness 1mm as it should...mounting and focus is spot on....in other words I have a cheap chinese adapter that cost me 12$ including shipping from HKG and I cannot complain in the slightest.

 

[johannielscom]

...There is no greater pain in the ass than an off spec adapter when you waste time trying to figure out why your images are soft.

I got a cheap one from seller "jinfinance" on that auction site, and it makes the Jupiter-3 lens register correctly at the M6 and M3 at close focus. So, in fact it made my lens sharper!

In general I agree original adapters are the thing to use, but when it comes to Jupiters it might also be a benefit to have a cheap adapter fitted. YMMV.

 

[jmkelly]

If you are just buying the adapter to use with one Jupiter lens, go for the ceahp one - you are probably going to have to re-shim the lens to focus correctly anyway, and the process will also correct any focus issues inherent in the adapter.

If you think you might ever own more than one LTM lens you want to put on your M, buy a Leica or CV part. You may still need to shim your Jupiter, but probably not your Nikkor P.C or Canon 50/1.5.

 

[bhop73]

I've got a Voigtlander 50mm LTM adapter for my Canon 1.4 lens. It also is "crooked" when it's screwed in all the way. (like Acliff's photo above) It doesn't affect the performance, no big deal.

 

[Acliff]

Just printed off 2 more rolls of film, and there doesn't seem to be anything wrong with the focus, so nothing really to worry about.

 

[crawdiddy]

Why WOULDN"T you buy this adapter for $16? Shipping is free. You could purchase all 3 for less than you would spend on a single Voigtlander or Leica adapter. I have a set of them purchased from Macau. The only thing I don't like about them is that I had to purchase from China. They work fine.

 

[ferider]

I've got a Voigtlander 50mm LTM adapter for my Canon 1.4 lens. It also is "crooked" when it's screwed in all the way. (like Acliff's photo above) It doesn't affect the performance, no big deal.

For classic Canon and Nikon LTM lenses this is normal. The idea is, I believe, to be able to see the focus point through the RF.

For CV lenses this is not normal. Their inf. focus mark should point to 12 o'clock. They can be adjusted though, within limits, see http://ferider.smugmug.com/Technical/Lenses/CV-Lens-adjustment/1975455_N6tET

I also like to stick to Leica and CV adapters.

Roland.

 

[Acliff]

For classic Canon and Nikon LTM lenses this is normal. The idea is, I believe, to be able to see the focus point through the RF.

For CV lenses this is not normal. Their inf. focus mark should point to 12 o'clock. They can be adjusted though, within limits, see http://ferider.smugmug.com/Technical/Lenses/CV-Lens-adjustment/1975455_N6tET

I also like to stick to Leica and CV adapters.

Roland.

You sir, are a scholar and a gentleman.

Rescrewing the mount seems to have done the trick, it is now only 2mm over, so 12.10am, rather than 1am.

Thank you very much!

I've attached what it looks like now:

 

[Livesteamer]

Another vote for the quality adapters. A long time ago, I owned the worlds ugliest Nikon F. It was so battered that I took it into the machine shop where I worked and asked them to measure the film plane to lens flange distance. It was still square and accurate to a ten thousandth of an inch. That's about 1/50th of a human hair. This demonstrates the accuracy that Nikon and others strive for. An inexpensive adapter cannot be machined to this kind of tolerance. Buy Quality and hang on to it. Oh, and the worlds ugliest Nikon F worked just fine altho I later sold it and traded up to an early, black, plain pentaprism F. One of my few good investments. Joe

 

[chenzhaohy]

I have a voigtlander 50mm adapter in new condition which I never used.
Let me know if you are interested.