Super Ikonta 532/16 -- A Whine and Questions

[KoNickon]

Recently I got a beautiful one of these; postwar model. Only problem with the camera is that using the focusing wheel is a painful experience since it's very stiff; turning the front of the lens instead is also difficult, because the lens front ring doesn't afford much of a grip. So last night I applied some grease to the lens helicals -- didn't remove the lens front element, but by removing the face plate around the lens and turning it to minimum focus I was able to apply enough grease to make the focusing a lot easier.

The problem is that in working the front element back and forth to get the grease distributed, the geared ring that surrounds the front element became disengaged from the sprocket that engages the RF prism assembly. (I should have put the face plate back before rotating the lens, since that would have kept the geared ring in place and engaged with the sprocket.)

So now I have to figure out how the heck to get the RF back in alignment. Last night I got the prisms aligned at infinity (the moon), but nothing else lines up. I've read writeups about having to take the two prisms apart and change them relative to each other (and all the while taking care that they don't fall out). But shouldn't I be able to simply keep the prism assembly together and, by removing the geared ring and turning the sprocket that engages the geared ring, rotate the prism assembly until I find the proper orientation? Seems like disassembling the prism assembly and moving the two prisms relative to each other -- in effect, changing the factory orientation of the two prisms -- is just asking for an extremely long and tedious adjustment process.

Thoughts?

 

[ZeissFan]

This is a two-step approach. First, you must collimate the lens to infinity. Then you must calibrate the rotating-wedge rangefinder.

As I recall, you calibrate the rangefinder with the lens face ring and shroud removed. But leave on the serrated ring that connects to the rangefinder wheel and rotating wedge prisms. However, don't turn the lens while calibrating the rangefinder.

Note where the notch sits for the infinity mark.

Recheck that infinity focus hasn't moved. Then reassemble and recheck infinity focus and rangefinder calibration. You might have to lift and turn the ring with the serrated edge, so that it lines up with the lens face ring and that infinity aligns with the mark on the lens shroud.

If you removed the front element/group entirely, there is a chance that the grub screws will no longer align with the predrilled holes. You can then either remove the lens and rethread it until the holes align, or you can drill new holes.

If you remove the middle lens element, you almost always have to drill new holes for the grub screws.

I haven't worked on one of these for a few years, but it's not as complicated as it sounds.

 

[KoNickon]

This is a two-step approach. First, you must collimate the lens to infinity. Then you must calibrate the rotating-wedge rangefinder.

As I recall, you calibrate the rangefinder with the lens face ring and shroud removed. But leave on the serrated ring that connects to the rangefinder wheel and rotating wedge prisms. However, don't turn the lens while calibrating the rangefinder.

Note where the notch sits for the infinity mark.

Recheck that infinity focus hasn't moved. Then reassemble and recheck infinity focus and rangefinder calibration. You might have to lift and turn the ring with the serrated edge, so that it lines up with the lens face ring and that infinity aligns with the mark on the lens shroud.

If you removed the front element/group entirely, there is a chance that the grub screws will no longer align with the predrilled holes. You can then either remove the lens and rethread it until the holes align, or you can drill new holes.

If you remove the middle lens element, you almost always have to drill new holes for the grub screws.

I haven't worked on one of these for a few years, but it's not as complicated as it sounds.

Thanks, Mike -- yes, in order to shift the serrated ring at all, I'd need to remove the lens face ring. The problem, it seems to me, is that it's possible to get the prisms to align at infinity but nowhere else. Presumably that's also true at other distances as well. When that happens, does that mean the prisms are 180 degrees off? It's as if there is only one correct setting (obviously) but finding that is what's tedious. Hard to know how many revolutions of the sprocket that engages the serrated ring take the prisms through infinity to minimum focus.

 

[Robert Lai]

This is where it gets tedious. You'll notice that the two prisms rotate in opposite directions when the lens is focused. Since you have infinity focus lined up, you need to physically lift the two prisms, maintaining their alignment with each other. Then, put them both back in one gear teeth rotated, and screw the plate on. Now check infinity and minimum focus again. If the minimum focus is still off, then remove the plate, and rotate the prisms one more gear teeth. Pick a constant direction of prism rotation (e.g. clockwise). If minimum focus is really out, then you may want to move two gear teeth at a time, until you are close to the correct alignment.

Hopefully, you'll find the proper orientation in under 2 hours or so of trial and error.

 

[KoNickon]

Oh brother. 🙂 Let me see if I understand -- you lift and shift the two prisms as a unit? It's not like you move one of the prisms one tooth clockwise and the other prism one tooth counterclockwise, right? If so, that would be a friggin' nightmare to keep straight!

By the same token, though, shifting them as a unit seems inconsistent with the whole exercise -- if the two prisms are in alignment at infinity, why would shifting them together cause a change in the focus? Don't you need to change their orientation as to each other in order to change the focus?

 

[ZeissFan]

If you haven't removed the prisms, then you simply need to rotate the serrated wheel until you find alignment at infinity. Then you lift the serrated ring and put it back down so that the lens face ring distance scale also is at infinity when it is placed on the lens and the notch in the back mates with the tab on the serrated ring.

If you have the camera in front of you when you read this, it will make more sense.

Of course, make sure that you recheck lens collimation along the way.

 

[KoNickon]

Right, that's what I did -- but it ONLY aligned at infinity. So I think I've maybe got the prisms 180 degrees out of alignment -- with everything back together, turning the focus back toward minimum distance seems to actually go past infinity. That is, the RF image seems to move beyond it. But I think I agree with you that there should be no need to remove the brass plate that holds the prisms in place, and move the prisms. I just need to turn the gear that meshes with the serrated ring until I've got agreement at infinity and down through the focus range.

Yes, I need to keep checking actual lens focus at the film plane.

 

[KoNickon]

Success. I rotated the gear that meshes with the serrated ring, and which turns the prisms, until I found a different infinity focus -- surprisingly, not 180 degrees or 90 degrees from the spurious infinity focus I had found earlier. I carefully replaced the serrated ring, put the shroud back on (since the shroud keeps the serrated ring meshed with the prism gearing) and lo and behold, it aligned properly through the entire focusing range. I noted that the two slots on the brass geared ring in which the front prism is set were perfectly horizontal at proper infinity. Hmmm, coincidence? I would think that would be an extremely helpful thing to design into the camera to aid assemblers and repairers, but that might have been expecting too much from ZI.

One thing Zeiss Ikon did do is drill very deep countersinks for the grub screws that hold the lens distance ring in place, so there's no inadvertent misaligning of the distance ring when you reinstall it. My very rough lens collimation method (using Scotch tape as the ground glass) raises a touch of doubt in my mind whether the factory collimated it absolutely precisely, but I am not about to act on my second guessing -- in any event, slightly shifting the lens would make it hard to reposition the grub screws, given the existing countersinks. (A far cry from the Moskvas, which require you to very carefully mark where these screws are positioned when you remove the distance ring).

 

[63alfred]

Thanks for posting this I had the same problem with my 532/16 and your suggestion toe find a second "sweet spot" for the prisms did the trick!