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Jim23
Joined: 08 Sep 2001 Posts: 129 Location: US/Greater Cincinnati, Ohio
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Posted: Wed May 28, 2003 7:28 pm Post subject: |
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I have an early Century Graphic with a self-cocking shutter that does not have X sync like the bit later Century X-F-M shutter does. When I fire an electronic flash, it misses entirely. I believe the shutter was designed for obsolete F-type lamps (SM/SF) or M-type at 1/25 or slower. Is there a way to modify the flash contact to remove the 5ms or so delay to that the shutter will X-sync at all speeds (1/10 thru 1/200) like the later model? I want to let my daughter use this camera (instead of the good one with the Compur...). |
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Les
Joined: 09 May 2001 Posts: 2682 Location: Detroit, MI
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Posted: Wed May 28, 2003 9:00 pm Post subject: |
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Speed costs money, how fast do you want to go?
the answer is yes, but it might cost enough that it would be cheaper to let your daughter use the compur.
You'd need to open it up and look inside, What you want to do is have the contacts close when the shutter is wide open. Kodak occompished this buy completely removing the gear train of a Flash Supermatic adding a couple of brass contact where one would be bumped by a pin on the shutter as it hit wide open. Poof! A Supermatic X.
Now it may be possible to occomplish the same thing without a major operation. If shutter guts make you squeemish, then send it to SK Grimes. They are still in business and I'm sure they can occomplish the task. For how much..... I don't know.
_________________ "In order to invent, you need a good imagination and a lot of junk" Thomas Edison |
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Jim23
Joined: 08 Sep 2001 Posts: 129 Location: US/Greater Cincinnati, Ohio
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Posted: Thu May 29, 2003 3:22 pm Post subject: |
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I opened the shutter and found out how the sync contact works. The flash sync fires when the blades first start to open. I may be able to reposition the contact (or notch it) so that the blades are 100% open before the sync fires. I was hoping by this post to find out if someone had done this.....
I'm willing to risk it since the camera/lens is far from even EX condition (repaired cracked housing, etc.) I had originally purchased it for parts. My 12-year-old daughter is fascinated by the prospect of being able to take pictures with it and wants to take flash shots with an old Vivitar 2500 flash. If she can learn to remember to advance the film, pull the dark slide, etc. she'll be set to use any adjustable camera in the future.....and I can show her how to develop the film and make prints (just like my Dad did with me in 1965 when I was her age). |
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clnfrd
Joined: 26 Mar 2002 Posts: 616 Location: Western Kentucky Lakes Area
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Posted: Mon Jun 02, 2003 1:53 pm Post subject: |
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Jim...here's how to do it. With your shutter's internal parts exposed...bi-post connector at upper right, you will see that the lower-most post is connected to an insulated strip which is your flash contact. At the end of the contact is the rotating piece that opens the shutter and it has a tab on it that contacts the insulated strip to ignite the flash as the shutter starts to open. The insulated strip has two screws, one that is connected via a piece of copper to the post (loosen this screw)...and one in the middle of the strip. Remove this screw. Connect a continuity checker (ohm-meter) across the bi-posts. Rotate the piece that opens the shutter, and at the same time, move the lower end of the strip to the left to a point where continuity is achieved when the shutter is wide open. Tighten the top screw. You can't replace the middle screw, so use a dab of epoxy to secure the middle of the strip. Re-assemble the front plates and you're done. Fred. |
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Jim23
Joined: 08 Sep 2001 Posts: 129 Location: US/Greater Cincinnati, Ohio
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Posted: Mon Jun 02, 2003 2:21 pm Post subject: |
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Thanks Fred! I will do this. I did try the sync at all speeds earlier 1/10 thru 1/200 and all of them prematurely fired the sync (i.e. just the right delay for a SM/SF lamp). I'll let you know how it goes. |
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clnfrd
Joined: 26 Mar 2002 Posts: 616 Location: Western Kentucky Lakes Area
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Posted: Tue Jun 03, 2003 7:52 pm Post subject: |
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The lower end of the flash-contact insulating strip will actually end up about as far left of its original position as it can go to achieve perfect x-sync. Also, when you removed the shutter cover, the gear train for the slower speeds "unwinds". When replacing the cover, you'll have to be sure that the associated "tang" ends up in the cover opening where it belongs. FWIW, I used a dollop of contact cement under the middle of the strip to secure it, so I could always change it back to original if I wanted to. Anyway, I see a perfect brilliant circle, looking through the lens at a white card with my Heiland Strobonar 64B at all shutter speeds. Fred. |
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