Possible to swap shutters on old folder?

[sleepyhead]

Hello all,

I have an Ensign Autorange 220 folder (really nice small folder by the way), which I would like to do some transplantation work on:

The original 3-element 75/4.5 Ensar lens in Compur shutter has been replaced by a 5-element 75/2.8 Schneider Xenar (yeah!), in a Prontor II shutter (booh!).

The Prontor II has "old fashioned" speeds (1/5, 1/10, etc.) and a maximum speed of only 1/150th.

I have managed to figure out how to unscrew the lens elements in order to clean them, but now would like to know if it's possible to replace the Prontor II with something like a Compur or Compur Rapid shutter.

Has anyone tried this, or know of a repirperson would could do it?

Thanks in advance for your help.

 

[Roger Hicks]

Dear Yaron,

Swapping shutters is entirely possible: see

http://www.rogerandfrances.com/subscription/ps how re-shutter.html

But there are two points to consider. One is maintaining identical separation (covered in the module) and the other is maintaining RF coupling, though presumably you already solved that for the Xenar.

Cheers,

R.

 

[sevo]

Shutters tend to come in standard sizes where the camera and lens thread and spacing are concerned, especially so if you stay within one maker (like the Zeiss empire that made Prontor and Compur). So it is generally possible. However the trigger tabs coupling the in-body release contraption with the shutter are not generic and you'll usually be limited to releasing on-lens or with a release cable if you have a mismatched one. In severe cases the camera may even block the tab so that the shutter cannot be used at all. It often is difficult to find a shutter with a matching release tab or into which the original release tab can be transplanted - you may have to have a adapted tab made (or make your own, depending on your metal tools and skills).

 

[sleepyhead]

Thank you both for your replies.

I'm glad to hear that this is possible.

I wasn't the one who swapped the lenses on this camera, so I have no Idea how difficult that was. There appears to be several aspects of this idea (the lens cell separation, for example, and the coupling with the shutter release on the body) that are beyond my tinkering capabilities. Oh and possibly re-calibrating the aperture settings.

Still, I think I'll hunt around for a working Compur or Compur Rapid and have a look more closely when I have both shutters in front of me.

In the meantime, I'll shoot with the camera as it is, and enjoy the results.

 

[sleepyhead]

Also, thinking about this some more....

If I go ahead and attempt this, then I think I'll only try it with a Compur Rapid, since it's the slow, limiting, 1/150th speed that is my main "beef" with the Prontor II shutter. Going to 1/250 with a compur would help a little, but perhaps not worth the effort and risk of screwing up a fine working camera.

The Rapid shutter will get me to 1/400th or 1/500th.

 

[oftheherd]

I reckon camera hacking can be fun. However, you might just want to consider using a film with an ISO that suits your shutter speed and aperture range. The lens you have is good, and as long as the current shutter is accurate, or you can compesate, you may be better using it as is.

 

[sleepyhead]

I reckon camera hacking can be fun. However, you might just want to consider using a film with an ISO that suits your shutter speed and aperture range. The lens you have is good, and as long as the current shutter is accurate, or you can compesate, you may be better using it as is.

Yes, right now I have ISO 100 film in it'cause it's quite bright here. But, I find that at 1/50th I often see camera shake, so that leaves me with only 1/100th or 1/150th as hand-held speeds, and i find that quite limiting.

 

[sleepyhead]

Here is a sample picture from the camera in question. Unfortunately I have not scanned that many yet.

 

[JPD]

It's possible, but I wouldn't do it. Not only must you find a shutter that allows such a fast lens - it must also space the front and back lens groups correctly, and you must calculate so the aperture markings will be correct. And you will have to adjust the focus. Why not use the camera with slow film (max 100 ASA)?

Congratulations for finding a five element Xenar! It's quite a bit better than the four element. I have one on a pre-war Retina IIa, but it's called 2,8/5cm Retina-Xenon in this case. (see my avatar)

 

[citizen99]

A bit more pedantic detail 😉 ...
I have had several Autorange 220s (my favourite 6x6 folder!), and they came from the factory with at least Epsilon, Compur, Compur-Rapid or Prontor II shutters to my knowledge.

All of those Size #0 (about 58 mm diameter) shutters have the standard dimensions, 20 mm separation between the front and rear element faces, and 6 mm between the rear element face and the face of the shutter body that mounts against the lens standard. Lenses are usually the Ensar f4.5, but I have one with the f2.8 Tessar (in a Compur-Rapid), which might be encouragingly-similar to your f2.8.
A substitute Size #0 shutter that you might find is quite likely to have a mounting flange that can be accommodated in the lens standard hole (about 33 mm in the case of my cameras).

All of those makes of Size #0 shutter, from that era, that I have come across, have had the nominal 29.5 mm diameter for the front lens element thread. But, for the rear element thread diameter, I have found many original-manufacture deviations from 'nominal' ; e.g. 27mm on Autorange 20s, Weltur, Certo, Voigtlander ... and a 28mm on a f3.8 10.5cm Tessar on an Autorange 20! (and the mounting flanges of these would fit a 30 mm hole).

So, the issues that you would be most likely to find critical are the rear lens element thread diameter, and, as pointed out by sevo above, the shape and location of the trigger tab of the shutter.

 

[sleepyhead]

JPD, thanks for your comment.

citizen99, WOW thanks for that potentially really useful information.