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View Full Version : Replacement for Betax No. 5 Shutter?



junbug75
15-Feb-2013, 14:26
Hi,

Was wondering if a shutter existed that could replace my Betax No.5 with faster shutter speeds? I have it with a Gundlach Radar 12". Mine at best is running at about 1/25 set at 1/50 according to my repairman.

Thanks!

Jerry

C. D. Keth
15-Feb-2013, 17:03
I would be surprised if you can find a shutter large enough that had speeds any faster. Your best bet might be to find a betax or alphax (same dimensions) in better nick.

If the machining can be done to go into a copal 3 (I doubt it, the thread sizes front and back are nearly 20mm different), you could do 1/125th, but it would limit a 12" lens to f6.8. That if the machining is possible.

DolphinDan
15-Feb-2013, 17:58
Hi Jerry,

You might try these guys:

http://www.lensn2shutter.com/shutters.html

I bought a Alphax shutter from them for my 30" Red Dot Artar (in barrel when purchased) and got SK GRIMES to mount the lens onto the shutter, and it all went well.

Hope this helps.

Namaste
Daniel

Louis Pacilla
15-Feb-2013, 18:32
Hi Jerry,

You might try these guys:

http://www.lensn2shutter.com/shutters.html

I bought a Alphax shutter from them for my 30" Red Dot Artar (in barrel when purchased) and got SK GRIMES to mount the lens onto the shutter, and it all went well.

Hope this helps.

Namaste
Daniel

He will NOT gain any faster shutter speeds with an Alphax #5. It has the same 25th/50th s sec.

C. D. Keth
15-Feb-2013, 20:31
He will NOT gain any faster shutter speeds with an Alphax #5. It has the same 25th/50th s sec.

He could if he found one that's working properly.

Doremus Scudder
16-Feb-2013, 03:16
He will NOT gain any faster shutter speeds with an Alphax #5. It has the same 25th/50th s sec.

The OP doesn't specifically state that he needs faster shutter speeds; just that his Betax is running slow and may, by inference, be unreliable.

If that's the case, then a CLA might be in order. Replacing a spring or two in the shutter might get closer to that elusive 1/50th of a second, but likely never right on. A Betax 5 (and the Alpha) have just too much moving mass to get any faster.

If faster is really needed... let's see, I'm not familiar with Packard shutters, but I think they might be faster than 1/50th. How about a camera with a focal plane shutter? Just a couple of ideas. Copal 3 seems too small to me too.

Best,

Doremus

junbug75
16-Feb-2013, 11:09
Thanks for all the replies so far. I actually just got it CLA'd and top speed is a little above 1/20th. Might just have to settle with this and look for another 300mm with a more modern shutter. Thanks again!

premortho
24-Feb-2013, 15:16
I have a Betax, but not a #5. It seems to hit 100 good enough, especially if I excercise it a few times to get it warmed up. It is slow out doors in the winter though.