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Don Dudenbostel
20-Aug-2011, 10:40
In the day of the speed and crown graphic we used to sync our flash bulbs with the shutter by using a solenoid. By pressing a button on the flash gun or camera body the shutter was fired and bulbs fired at the correct timing.

I'm looking for a simple solenoid or electrical release that would screw into the cable release socket and fire the shutter with a battery operated module. I have one of the old solenoids but haven't figured a way to use it without major work.

Any ideas on existing solutions?

Thanks!

Don

johnielvis
20-Aug-2011, 20:42
well...I'm thinking of sometihing similar...howz about some kind of trigger mechanism for a spring.....the solenoid pulls back and releases the spring tension to the cablerelease.

does it have to be a cable release?....they do have solenoids that PUSH instead of pull, but they are NOT the graflex kind...them only pull---or just hook up that solenoid to the shutter trigger like graflex...use a string or staple for a tiny linkage, that's all...

you're going to have to be inventive---there's a million way to skin that cat...just use what you have laying around and you can do it Im sure

Robert Perrin
20-Aug-2011, 22:27
From vague memory I believe that solenoids with a cable release tip to screw into the shutter were made around the 1940's or '50's. Finding one now might be pretty tough, though. If you're interested in making one to screw into the shutter, one source I had bought small plunger solenoids from in the past, All Electronics (www.allelectronics.com), currently lists a 1/2" diameter, 1" long push solenoid with a 1/2" x 1/16" plunger in their catalog for $2.75. It's 12 volt rather than the 3 or 4.5 volt rating of most of the old press camera solenoids but it shouldn't be too hard to mate it to the tip cut from an old cable release and the plunger is about the right diameter. Be aware that although that company has no minimum order, it does charge a flat $7 for shipping, however there are a number of other companies that deal in similar--usually industrial surplus--products.

Don Dudenbostel
21-Aug-2011, 06:58
Thanks for the info. I think I can take the Graflex solenoid and use a short lever with the pivot in the center. When the solenoid pulls one side of the lever down the other side goes up and could push the plunger of the cable release. This would be easy to construct.

I also remember Linhof made an electrical release but I've never seen one in person and guess the price would be out of sight.

For the short term solution I ordered a cheap air release. This will probably solve my problem and if it does I'll order a better one.

My reason for wanting a remote release is to isolate vibration from my camera. I'm shooting with a Technikardan 23 and a digital back. I find that even with a cable release I get a tiny bit of vibration / movement in the camera due to the inability to hold the cable totally still during long time exposures. This tiny movement kills sharpness in the image. I think this would isolate the camera a little better. Im using a 5 series Gitzo carbon fiber tripod and know the camera is plenty solid. Its just extremely low levels of movement im introducing when holding the release causing the problem. Ive done a few experiments to test this yheory and think this will solve the problem.

Adamphotoman
21-Aug-2011, 10:31
This is a bit outside the topic but I believe that their may be other considerations. I think that some of the stability issue is the way that the standards are designed. When Betterlight showed their scanning backs at camera shows they had to hook them up to a variety of cameras. Horseman, Linhof etc... They found that any L shaped standard compromised stability. U shaped standards were much better. Mike Collette soon started to wedge something in the space between the bottom of the standard and the camera. This helped to prevent vibration. In a scan the vibration shows up as jiggly motion artifacts. In an [instant capture] with a long exposure it would show up as diminished sharpness. If you were to make a capture with strobes at a much higher shutter speed the problem should go away. The fact that the jigglies show up on various spots along the scan tells us that wind and floor vibration transmit to the image.
J Michael Sullivan does use an Tecknikardan L shaped standard with the scan back. He had SKGrimes machine his rear standard so that he could lock it down to prevent wind from creating problems. Even Mike has sacrificed his rear movements on an Ebony and bolted it together to increase stability.
When I set out to make an L shaped bracket for my Globuscope it also incurred jiggles. the Globuscope has a tripod thread on the 4 inch side opposite the film insertion. I had no choice but to make an L bracket. The camera is supported on the side and rests on a strip. There was some movement. So my solution was to use a double sided piece of foam tape. It worked. Much more solid.
A cable release is a must. So is extra support. Think about a possible brace for the L...

Grant

Sevo
21-Aug-2011, 14:59
Screw-in solenoids were still around in the nineties, intended to enable cameras with mechanical release to use wireless release systems. Cinematography rental places might know more - they tend to stock quite an array of problem solvers to match legacy cameras to modern gear.

Bob Salomon
21-Aug-2011, 15:15
"I also remember Linhof made an electrical release but I've never seen one in person and guess the price would be out of sight. "

Yes, for the Technar and Technika cameras. Short lived and finiky. It had a power pack that fit into the Anatomical grip and the release botton was at the top of the grip in the hole where a cable release is usually. The solenoid was mounted directly to the lensboard where the Cable Release Quick Socket is positioned. At the top of the solenoind was a threaded socket so you could still use a cable release if the battery died or the timing went off..

John Koehrer
21-Aug-2011, 15:22
I'm fiddling around with something similar but using a landing gear servo for RC airplanes. Rather than stopping somewhere in it's travel it goes from one end of the travel to the other. Travel time is on the order of a few milliseconds and, I think less likely to jar the camera.

Don Dudenbostel
22-Aug-2011, 04:59
Some good ideas here.

I agree the L standards are less stable than the traditional U standard. As mentioned above when shooting with strobes the problem is non existant due to the duration of the flash. The idea of wedging something under the front is a good idea. A firm foam might help dampen this vibration.

domaz
24-Aug-2011, 15:28
I have one of these fabled cable release solenoids- I think. It's a cable with a two prong plug on one end and a cable release end that can screw into a shutter on the other. Anyone know what the standard voltage is for these to test it? Then there's the polarity issue. I hope I don't blow the solenoid by hooking it up backwards.

vinny
24-Aug-2011, 15:48
I've brought this up more than once and I wish someone would made a wireless gizmo that would fire copal shutters and sell them on ebay for a reasonable price. Everyone points to the parts but I don't have the time or wits to make them myself.

search door lock actuator's as well. I don't know how well little 12v remote key batteries would work but it may be worth a shot.
http://www.parts-express.com/pe/showdetl.cfm?partnumber=330-010&utm_source=googleps

John Koehrer
25-Aug-2011, 15:33
I don't think there should be a polarity issue. The coil is energized and the armature is withdrawn or ejected. I've been wrong before!

For voltage I'd start with 1.5 & gradually work my way higher. Just momentary contact with the power, you wouldn't want to blow the solenoid. =P