135 Acall or adaptor Out of focus on M3?

[Skinny McGee]

Hello,

i just back a roll that I took with a generic adaptor from ebay that had good ratings with my M3 everyone is out of focus. i had used the lens on my 111A and everything was good except my framing because i did not have my external viewfinder set right... any thouhgts should I see about sending the adaptor back?

Thanks 😕

 

[Ronald M]

Measure the flange thickness of the adapter. If it is 1 mm +0 -001mm, it is ok

It could be the lens and without multiple samples of each or the proper measuring devices, it is hard to tell.

See if infinity comes up on a star at night and check with a 50mm lens at 1 meter from the film plane. In other words, check out the camera. The two calibration points on the RF are 1 meter and infinity. Leica 50 mm lenses are always marked at 1 meter.

 

[jlw]

Measure the flange thickness of the adapter. If it is 1 mm +0 -001mm, it is ok

The Leitz-brand adapters I have all measure 0.98-0.99mm on my digital caliper. This may be what Ronald meant to say, but I'm not sure where he intended the decimal point in "-001", so thought I'd better chime in.

The big thing is to make sure that the adapter isn't OVER 1mm thick. I've bought several generic-brand adapters that were 1.01mm or even more! (For some reason, I've yet to get one that's too thin.) This is definitely enough to affect focus with a 135mm lens; you'll probably be able to tell by noting that the lens doesn't quite reach infinity focus.

Many people aren't aware of this problem, so the fact that the seller has good eBay ratings may not guarantee that his adapters are within spec. I suspect there's a lot of sample-to-sample variation in third-party adapters, even ones with the same brand name on them.

 

[Les Lammers]

Maybe, just maybe...the lens was not properly mounted? Is this the first time you used an adapter?

 

[Skinny McGee]

No i have adaptors for all my screwmount lens but they are all Leica adaptors and never a problem....

 

[Les Lammers]

Hmmm....... Is this adapter a 'no name'? I got some from B&H on the bay and they are fine.