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View Full Version : Transferring lens from sinar db to copal shutter



Former Member 8144
14-Nov-2007, 16:26
Hi,
Just how easy is it to trasfer a lens on a sinar db board to a copal shutter?

Is it simply a matter of unscrewing the front and rear cells from the sinar db board and then attaching them to the copal...is it something I can do myself or does it need a technician etc?

The lens in question is a sinar siranon se 150mm F5.6

Thanks,

Marc

Ted Harris
14-Nov-2007, 20:30
should take about two minutes ..... you have it right that is all there is to it.

David Karp
14-Nov-2007, 20:31
I did not do it myself, but I have two Rodenstock Grandagon-N lenses that started out on Sinar DB boards, and were transferred to Nikon type Copal shutters. A local repairman, now retired, did it for me. It works great.

Apparently, you have to worry about things like spacing with some lenses. It was not an issue with mine.

If you can find a 150mm Rodenstock in a Copal shutter that has bad elements you might be able to pick the shutter up cheap and screw them right in.

Songyun
14-Nov-2007, 21:59
Hi,
Just how easy is it to trasfer a lens on a sinar db board to a copal shutter?

Is it simply a matter of unscrewing the front and rear cells from the sinar db board and then attaching them to the copal...is it something I can do myself or does it need a technician etc?

The lens in question is a sinar siranon se 150mm F5.6

Thanks,

Marc
Marc, it's you who just beat me in seconds.

Former Member 8144
15-Nov-2007, 01:45
Thnaks Guys.

The lens I was looking at (I'm sure you know which one!) has gone already but that's good to know for the future.

Cheers,

Marc

Phil Hudson
15-Nov-2007, 02:51
FWIW, I have had mixed success with transferring DB lenses into shutters.

On some lenses the spacing really IS an issue and the lens has not performed up to expectations while others have been fine (spacing on modern wide angles is critical).

On some lenses in original Copal shutters, there are small factory fitted shim rings to get the cell spacing just right. In theory this optical "trimming" is lost when transferring lenses to/from other shutters or systems. Even by transferring the shims there is no guarantee the new shutter has the exact same dimensions as the previous one.

I'm not sure whether Sinar used the same system of shims when mounting DB lenses in their factory but it's probably worth keeping all shims just incase they need adding later on to correct performance (this is rather tedious trial and error).

Phil

Aender Brepsom
15-Nov-2007, 03:29
Marc, it's you who just beat me in seconds.

No, it was no Marc. He is only 4th in the row.