Bessa II lens not aligned at infinity

[Brian Legge]

I picked up a relatively cheap Bessa II Color Heliar. The camera seems to be in fair condition over all but the projected image is way off at infinity.

If I unscrew the rear element about 1.5 rotations it seems closer to in focus looking at the image with ground glass. Unscrewing the front element doesn't seem to have as much effect. I'm not sure if the alignment issue is the distance between the front and rear element or if front standard is simply too far away from the film plane to focus correctly at infinity.

My initial thought was to try to put in a shim between the mount and the rear element to space it off a bit. Before I give that a shot, is there some other adjustment I should try? This seems like it may give decent far and near focus but doesn't intuitively feel like the right solution.

 

[thegman]

You're sure the ground glass is sitting on the film plane? Have you shot a roll in it yet? I'd try a roll of film before adjusting anything.

 

[Brian Legge]

I did shoot a roll. Very blurry - which matches what I'm seeing with the ground glass.

I just decided to throw the lens on a 2x3 graphic to see if I could isolate the issue to either the lens or the Bessa II body as I don't trust the front standard given their common problems. It looks better but its hard to be sure without shooting a roll with it. It may be a body issue.

 

[Vickko]

Can you get a good image with the 2x3 Graphic?

The Bessa II lens doesn't focus by moving the front group wrt. the rear. The whole lens moves. If you get a good image with the 2x3 Graphic, with the lens appropriately assembled, I would then pay attention to the bed of the Bessa II.

It isn't too hard to fix the slop that develops on the bed movement. Then the parallelism of the lens frame to the film needs to be addressed, and finally, the RF image alignment to the focus distance of the lens.

Mine turned out pretty good; I only needed to tighten up the slop in the movement. It is a pretty basic camera; I anticipate you can determine where the adjustments are.

Good luck

 

[Brian Legge]

I decided to clean the Bessa up a bit while the lens was off. Did they have some sort of deal with a lubricant manufacturer? I've never seen so much grease in a camera before. At least focus and film advance are a bit smoother now.

I played around with the focus mechanism a bit as well, seeing how it could be adjusted. Over all it looks like the problem I'm seeing is that I can't move the lens far enough back. Focused all the way back at infinity, it looks like ~25ft is in focus. Perhaps adding a shim behind the rear element probably helped at first because it changed the focal length of the lens slightly?

In any case, the rack is as far back as it goes and there are no shims behind the shutter, etc. Not seeing a way to move the shutter itself back. Out of time for camera play today - I'll have to pick this up again in a few days.

 

[Vickko]

My philosophy with camera repairs is that the camera once worked properly.

Can you see if there is some adjustment this is out of whack?

Or is the focus rack "one gear tooth out"?

Yes, shimming the rear cells will change the focal length, but may create all sorts of other aberrations in the lens that you don't want. So, not really a good solution.

 

[GaryLH]

I decided to clean the Bessa up a bit while the lens was off. Did they have some sort of deal with a lubricant manufacturer? I've never seen so much grease in a camera before. At least focus and film advance are a bit smoother now.

I played around with the focus mechanism a bit as well, seeing how it could be adjusted. Over all it looks like the problem I'm seeing is that I can't move the lens far enough back. Focused all the way back at infinity, it looks like ~25ft is in focus. Perhaps adding a shim behind the rear element probably helped at first because it changed the focal length of the lens slightly?

In any case, the rack is as far back as it goes and there are no shims behind the shutter, etc. Not seeing a way to move the shutter itself back. Out of time for camera play today - I'll have to pick this up again in a few days.

I would give Ken Ruth a call.. He fixed my Bessa II. It was suppose to have been excellent condition from seller. Turned out the front standard was misaligned plus some other issues. He did a good job of fixing it for me. He is pretty helpful...

Everything was out of focus for me as well..

His number is 831-423-4465.

Good luck
Gary

 

[Brian Legge]

My philosophy with camera repairs is that the camera once worked properly.

Thats what was throwing me off. I figured the focus may be a tooth off and checked it out. Unfortunately its as far back as it goes. Very odd as I can't spot a potential adjustment that would put it in to alignment.

Thanks for suggesting Ken. I haven't sent him anything before but I'll definitely consider it if I can't safely figure anything out soon.

 

[hanskerensky]

Once in a while somebody opens a camera and re-installs one or more of the lens elements the wrong way around. I have no experience with the Bessa II but maybe you could check if that's the case.

 

[Sarcophilus Harrisii]

You'll find some information here (I googled it "Voigtlander Bessa II focus adjustment").

From your description of the grease it sounds to me like it has been tampered with by someone who didn't really know what they were doing. Bear this in mind along the way.

I have to agree with Vickko. If you adjust the distance between the elements of the lens, as well as changing focus, you're actually meddling with the optical correction of the lens at all distances. Unless you have some good reasons to believe there is a need to change this dimension, I would defer trying this until other avenues have been explored, as it could lead to sub-standard results.

By checking the lens focus on the ground glass you are going about things the correct way. So many times I read here at RFF and elsewhere of owners confidently proclaiming their lens doesn't focus accurately because the rangefinder (or; TLR viewing lens; SLR viewfinder, etc.) image is off. This is really the slave or, secondary, adjustment for focus. The master adjustment is always the actual focus of the lens making the film image, so you are on the right track by correcting this first.

Keep us posted, it is an interesting problem, there will be a logical solution to it so keep at it.
Cheers
Brett

 

[Brian Legge]

That is the page I used today for disassembly and cleaning in general. Its a great resource - the only one I found online which was a bit of a surprise. Thanks - I'll post here next time I have an opportunity to work on it.

 

[citizen99]

All good points made above, just a few words of expansion ... I would never expect the lens-shutter assembly, as it came out of the factory, to have had any shims internally (by which I mean between the screw-in lens elements and the shutter body). However it is fairly common to find some shims between the shutter-lens assembly and the standard. I have a Bessa Rangefinder, the very similar ancestor of the Bessa II, and have worked on a few, and these have had shims behind the shutter, as have other Voigtlanders and other brands of folders. The total absence of shims behind the shutter of yours and the prolific greasing as has been pointed out is suggestive of previous tampering.

Just for the record here is another picture.