Shutter Problem

[moltogordo]

I recently purchased a very nice Schneider Linhof select 240mm f5.5 Tele-Xenar in a Synchro Compur shutter. Everything was working fine until I planned a shoot (tomorrow), loaded up the holders, and then of course, the shutter ceased to work - it just jammed, and would not fire.

Frustrated, I screwed out the Nikkor-W lenses (180mm f5.6) from the Copal 1 shutter they were in, and put the orphaned Tele-Xenar glass into the shutter, and lo and behold, it worked.

Couple of questions:

1) even though the Schneider seemed very sharp when I focussed on some lettering on a milk carton on the table, and I'm going to have to use the Schneider/Copal combination tomorrow in my shoot, which involves portraits, is this a good thing to do?

2) I realize I'm going to have to get the Synchro-Compur fixed, but curiosity led me to take it apart. I fixed the jammed cocking lever, but couldn't get the shutter blades back in properly, so had to put them in a second envelope to send away to some unlucky repairman.

3) I have NOT had good luck with these older Synchro Compurs, and I'm left wondering if I just shouldn't buy some cheap scratched lenses with Copal #1s, and put the Schneider lenses in those, pitch the Compurs, and call it a day. My 150mm Schneider is in the same boat, with it's jammed shutter.

Any suggestions?

[IanG]

The aperture scale of the Copal from the 180mm probably won't be correct for the 240mm lens.

Compurs are reliable shutters so get them repaired they'll last years afterwards. It'd be easier and far cheaper to find spare Compur shutters, all the 135mm & 150mm f4.5 Tessar/Xenar and equivalent design lenses are in Compur #1 shutters.

Ian

[moltogordo]

Thanks Ian. The directness and tone of your reply has inspired confidence. I'll ship the shutter out this weekend to the camera repair guy in Victoria, and probably my 150mm f4.5 Tessar as well. I will confess I've never had them serviced, and bought them used. I'll take your word to stick with the Compurs.

I'll shoot a couple of extra shots and develop them individually to take into account the probability of having to make an adjustment in developing times based on your assessment that the aperture values will probably be different. I'll be shooting between f5.5 and f8, so I would think one stop out might be where I'm headed. I'm using FP4 and D76 so I'll be able to push or pull and still get good negs.

[IanG]

My experience is that Compurs are the more robust of the shutters. I've some spare Compur shutters for emergency use, I picked up a 135mm f4.5 Agfa Solinar in a Compur #1 at a Flea market a couple of years ago, the shutter's fine, no flash sync, people aren't interested in the lesser known lenses so the often sell very cheaply. With the older rimset Compurs it's easy to switch the aperture scales.

Ian

[LabRat]

The Synchro Compurs are great shutters, but are built to tight tolerances, so if it has been sitting for awhile, the moving parts inside might oxidize slightly, creating drag that snarls up the entire mechanical system... Send it out... (Don't try this at home kids, because they are fussy to get running well again)

I have an old Rollei 2.8C TLR that had a sluggish/sticky Sync/Comp shutter and some wind issues, that I had gotten about 35 yrs ago... (I'm a tech) but I sent it out to a great old tech I knew because I didn't know this camera, and I knew the shutter could be tricky... Came back working great!!! I hadn't used this camera for about 25yrs, but I recently I pulled it out and set the speed to 1 sec, cocked it, fired it, and it sounded right on!!!! He did a great job on it!!!!

Fire these shutters a few times every month or so if in storage unused, (and those old Hassy lenses) to keep everything moving...


Steve K

[moltogordo]

What you are both saying makes perfect sense. I'll send the shutter in, and when it's returned, follow your advice. Thanks so much.

[Peter Yeti]

It's all said already. Stick with the old Compurs, they beat the crap out of Copals. I have a dial set Compur from 1923 that's way more accurate than my latest Copal. The old dial set ones are very easy to service, the rim set ones are much more difficult but no problem for a good service technician.

If you have to use the shutter of the 180mm with your 240mm tomorrow, just multiply the f-number on the shutter with 4/3 to get the correct f-number. No guess work necessary. If you have an accurate vernier calliper at hand you can measure the cell spacing and overall length of the Tele-Xenar in the original shutter and compare it to the values in the new shutter. If both are the same you should be on the safe side.

Good luck,

Peter

[IanG]

It's all said already. Stick with the old Compurs, they beat the crap out of Copals. I have a dial set Compur from 1923 that's way more accurate than my latest Copal. The old dial set ones are very easy to service, the rim set ones are much more difficult but no problem for a good service technician.

If you have to use the shutter of the 180mm with your 240mm tomorrow, just multiply the f-number on the shutter with 4/3 to get the correct f-number. No guess work necessary. If you have an accurate vernier calliper at hand you can measure the cell spacing and overall length of the Tele-Xenar in the original shutter and compare it to the values in the new shutter. If both are the same you should be on the safe side.

Good luck,

Peter

Peter, the normal ratio of: f stop = Focal Length / Diameter of the aperture doesn't hold true for a telephoto lens like the Tele-Xenar.

For example I have an ex-Military 17" (420mm) Telephoto with a marked maximum Aperture of f5.6, it has no aperture scale unfortunately so I'm about to make one. Maximum aperture diameter wide open is 44.83mm the calculates to f9.59. But of course a Telephoto has a Nominal Effective Focal length, in practice it's actual focal length is much shorter so measuring the Aperture to film plane at Infinity focus of my lens is around 25cm which calculates to f5.58.

So the OP can't just multiply the marked F stop by 4/3.

Ian

[IanG]

The 240mm Tele-Xenar is likely to be slightly faster (in terms of Aperture) than the 180mm Nikkor by around half a stop of the marked stop.

Ian

[Peter Yeti]

Ian,

Thanks for correcting my error, you are right of course. I overlooked that it's a tele photo lens.

Peter