Is this a normal behavior when focusing an m mount lens?

[twotroy]

I recently purchased a Voigtlander Ultron 35mm F1.7 lens and experiencing the following issue.

On both my M2 and M3 bodies I set the lens at infinity and when I start to focus on something a meter away (as an example) the focusing patch does move right away when I start turning the focusing tab on the lens. There is a slight delay, maybe about a second, before the image moves for alignment. Is this normal? Is this a bad copy of a lens?

I tested the same lens on a digital leica m262 and this similar behaviour doesn't seem to happen or not as obvious.

Other m lenses (28mm summicron or zeiss sonnar 50mm 1.5) do not have this issue with the delay on the exact same M2, m3 and m262 cameras.

It feels like maybe there is a problem with the lens but I'm not 100% and looking to see if anyone has any ideas. Maybe I'm missing something here

 

[Richard G]

Do you mean does NOT move? I get this with my Zeiss 25 I think, but only at close focus, not if I start at infinity.

 

[reuno]

Finder is coupled only from 0.75m, so if your lens allow you to go below that distance, it's up to you to judge. Looks like the minimum focusing distance for your lens is 0.5m, so it seems all normal to me.

 

[rcubed]

I had this issue with my M2 as well and followed this to get it working:

https://www.rangefinderforum.com/forums/showthread.php?t=119823

 

[Huss]

Finder is coupled only from 0.75m, so if your lens allow you to go below that distance, it's up to you to judge. Looks like the minimum focusing distance for your lens is 0.5m, so it seems all normal to me.

The OP is starting from infinity.

 

[rbiemer]

If what you're describing was happening with different lenses on the same body, I'd have to think that the rf mechanicals were in need of attention.
But with this happening with one specific lens on different bodies, I have to think that there is something about that lens.
Does the focus cam on the lens have any obvious damage or wear?
I also wonder if the focus "arm" and roller on the M262 is slightly different than those on the M2 and 3 cameras?

Rob

EDIT: is your Ultron lens LTM or M mount? If LTM, perhaps there is something about the adapter that's not quite correct?

 

[Rob-F]

If what you're describing was happening with different lenses on the same body, I'd have to think that the rf mechanicals were in need of attention.
But with this happening with one specific lens on different bodies, I have to think that there is something about that lens.
Does the focus cam on the lens have any obvious damage or wear?
I also wonder if the focus "arm" and roller on the M262 is slightly different than those on the M2 and 3 cameras?

Rob

I would have to think that too, except that if it works correctly on the M262, then that argues against there being anything wrong with the lens. And I'm stuck as to what could be going on. My 90mm Elmarit has a sliding piece that couples the lenses focusing cam to the camera's cam follower. When the lubricant gets old, it can get sluggish and cause this kind of problem. But I can't imagine that a 35mm lens would have this kind of mechanism. The M2 and M3 are fine with other lenses. The Ultron is fine on the M262. I wish I could think of an explanation.

 

[Ko.Fe.]

Is it M or LTM mount?
If LTM, perhaps it was modified for close focus on M240 and it is somewhat slightly different on old M2 and M3.