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uniB
8-Nov-2007, 13:51
Hi, I've got confused again, can anyone help me?...

I've got a lens that I bought secondhand which has a Copal shutter. All's fine, until I came to put a cable release in it to use it.

It appears to be a self cocking shutter but there's no socket to screw a cable release in that I can see there's one on the other side of the shutter but that just opens and closes it when y ou press/release the button. The shutter fires correctly if you use the lever but the two bits (not a technical term there!) confuse me.

I've posted some pictures of it at: www.dav-t.co.uk/shutter.html

If someone could tell me what's going on here I'd greatly appreciate it! :confused:

Dav

Turner Reich
8-Nov-2007, 14:42
It's a press shutter and it appears to have the socket closed off by a cable release that was broken off. You might be able to unscrew the piece then you can use a cable release as usual.

Dave Parker
8-Nov-2007, 14:49
Somebody broke of the tapered end of the a normal cable release in the socket, you will have to remove the broken piece before you able to attach a new cable release to trigger it, not that big of deal, but could be tedious to do.

Dave

uniB
8-Nov-2007, 14:55
oooh I see, I wondered if that was the case... right, I'll get the mini screwdrivers out...

great, fixed it, all working fine now thanks for the help :)

Dave Henry
8-Nov-2007, 18:06
It also appears that someone put Nikor elements in this older shutter. You should check the sharpness to make sure the elements were spaced properly like the original shutter.

uniB
9-Nov-2007, 01:51
Thanks Dave, that sounds a bit worrying, I'll make sure I use it when I next go out so I can check its sharpness.

Dan Fromm
9-Nov-2007, 04:01
Dave, until proven otherwise a #0 is a #0 is a #0.

Dave Henry
9-Nov-2007, 23:26
Dan thanks for the clarification. I'm not an expert in anything. I'm only going by what others have advised me in similar situations on this forum that not only do you have to check the aperture scales to make sure they match the focal length elements you are putting in that shutter, you need to make sure that the original elements are spaced properly as well. I'm told that thin shims are sometimes used in lenses to assure this spacing. Again, I'm not a lens designer. I only shoot with them.

If you want more expert information, check my replies to take you to my original question on this same subject.

I think uniB needs to check the aperture scale as well.

Maybe Carol could address this area as she would certainly qualify as an expert.

Dave Henry
11-Nov-2007, 09:14
Dan, I'm not convinced that a "0" is a "0" is a "0".

I was browsing through eBay this morning and found another mis-matched lens/shutter to illustrate my point of just being aware of what you're buying. Check this listing 200170373709.

I'm finding there are a lot of sellers either knowingly or unknowingly selling cobbled up lenses that may or may not have been properly calibrated for sharpness. In this case the f:stop band (f:9) didn't match the f:5.6 lens mounted in it. I would be wary of the spacing sharpness as well.

Can any qualified technician (Carol, S.K. Grimes folks) address the spacing issue of elements and mis-matched f:stop markings in a non-original shutter?

Dan Fromm
11-Nov-2007, 10:10
Dave, all #0s have the same threading inside and out and the same flange-to-flange distance. Aperture scales can be replaced.

What can be a killer for swapping cells from one #1 to another is the exact position of the diaphragm. For example, I have a pair of 80/2.8 Planar cells that go perfectly into a #1 Compur and a #1 Copal, both cock-and-shoot, but the rear cell hits the diaphragm in #1 Copal Press and #1 Prontor Press. According to Jim Galli, who puts G-Claron cells in the same #1 Copal Press that won't take my Planar cell, G-Clarons aren't a problem.

Another killer, that I think is limited to #00s, is the "shoulder problem." Some lenses' cells flare out a little above their threads and the shutter has to be machined so they'll seat properly.

Of course you know all this.

And, since you've been to their sites, you know too that Carol doesn't replace/engrave aperture scales. Steve's successors do and they also machine shutters to solve the shoulder problem.

Dave Henry
11-Nov-2007, 10:58
Dan, Thanks for the information. When an aperture scale is replaced, is it some type of sticker or is it a nice plate or something?

Dan Fromm
11-Nov-2007, 11:41
Dan, Thanks for the information. When an aperture scale is replaced, is it some type of sticker or is it a nice plate or something?Depends. Some are bits of metal held on by screws. Not by glue, AFAIK. Others, as for example the scale Steve put on a Copal 0 for my 38/4.5 Biogon, are engraved.