voigtlander folder focus question

[De_Corday]

Hey gang. Not sure this is the ideal place for this question. I have an old Voigtlander 6x9 folder. One of the zone-focus types. The focus ring moves, but it doesnt do anything. near as I can tell with some ground glass, the focus is at or near infinity, and the ring simply rotates. Front element rotates with it. Nothing moves in or out.

The camera is just a kick-around I bought for cheap. Any recommendations on how to get it focusing again?

 

[KoNickon]

So (and forgive me if I'm asking you to repeat what you've already said) -- the focus ring has no movement forward or backward as you go from infinity to closest distance? If the front element is turning with it, then the front element should be moving in its helical (and thus should be focusing). But if it's not focusing, as you say is the case, I don't see how the front element can be turning also without the front element and focus ring coming right off the front of the camera.

Can you tell us the model of the camera, or give us some pictures of it?

 

[De_Corday]

You're describing the problem exactly. Hence my confusion.

Here's the business end:

 

[GaryLH]

I had the same issue w/ a Zeiss folder that I bought used for real cheap.. Well it turned out nothing was ever in focus because someone had taken the lens apart and did not mark the proper thread start location to put the lens back on..

The other possibility that I can think of is that the lens focus is actually frozen in the helicoid due to dried out grease. If I remember correctly (please correct me), some of these lenses had a external collar that was used to move the focus mark around.. It could e that the set screws are loose and the front collar is just spinning.. Anyway I can be all wrong here and going on bad memory.

Gary

 

[De_Corday]

Well the front element is moving so I don't think it's dried grease, but the helicoil doesn't feel engaged at all... If I take it apart, what should I expect to see?

 

[sevo]

If the front element glass turns with the ring, it might still be focusing - makeshift ground glass replacements like a strip of frosted tape across the film window are no particularly reliable test. The front cell displacement is very minimal, less than a millimetre for the turn from stop to stop, so that there is not much of a visual confirmation that it works.

If you can definitively confirm that it is not focusing, the rear element of the front cell has broken loose from the shutter and the entire front group (both elements) is moving rather than the front only - that may happen if the grease in the helical between the both dries up.

 

[De_Corday]

huh. Good point. I am using makeshift ground-glass... both tape, and holding an SLR split prism at the focal plane while adjusting the focus ring. I'm not noticing any movement in the split prism with that admittedly highly unscientific test.

The rear element is not moving when I turn the focus ring. Is there truly only a mm or so of front cell displacement? I feel like I've seen this style of camera before and been able to tell, but never this exact model. The focus ring moves very freely.

I might just need to keep shooting with it.

 

[GaryLH]

If the helicoid is actually moving, when look down from above u should c the change in distance between inf (absolute closest) to closest setting (absolute farthest), when u use a reference point like the front standard mount plate. It does not take much in terms of distance. I can't remover off the top what the delta is though.

This only pertains to a front element focusing design though.

Gary

 

[De_Corday]

I see virtually no change in distance between the little red indicator arrow and the plate with the distance markings through the sweep of the focus ring.

 

[De_Corday]

So, am I understanding folks correctly that if it isn't focusing now, its most likely a helical-allingment problem and my chances of fixing it are... small?

 

[sevo]

So, am I understanding folks correctly that if it isn't focusing now, its most likely a helical-allingment problem and my chances of fixing it are... small?

As I said, if it isn't focusing, it is probably the helical locked up due to dried-up grease - that would be a fairly easy and essentially free DIY fix, with plenty of how-to's on the net (search "Isolette stuck focus ring" - Agfa used the worst grease in the trade so theirs are all stuck nowadays).