Hi there, Original message with question:
"I have two Packard shutters that I want to use in cameras I am building. When I squeeze the rubber bulb, both shutters stay open until I release the bulb, as if it was on a "B" setting of a modern shutter. Is there a Packard shutter that closes instantaneously without releasing the bulb?" Over the years I've seen two different models of Packard Shutter; one has the "instantaneous" option and one doesn't. The ones with this "I" setting seem to be more common, but I'm sure there are plenty of both. Here's how to find out which model of shutter you have. Look at the back of the shutter, the side that will face the inside of the camera if you mount the shutter on the back of a lensboard, or in the camera itself. On the right hand side you'll see the pneumatic brass tube arrangement which opens and closes the shutter. If it has the "I" option, then looking at an angle of about 11 o'clock, you'll see a small protuberance, a closed cylinder maybe 1/16" in diameter sticking out from the body of the shutter. On the front of the shutter there will be a corresponding hole. If there's felt on the front of the shutter you probably won't be able to see the hole, but you'll be able to stick a small nail or un-bent paper clip into the hole. It will go through the body of the shutter into that cylinder and stop when it reaches the end. Important: Try this when the shutter is closed. This hole is a for a pin which came with the shutter when it was new. When the pin is inserted in the hole, you squeeze the bulb hard and the shutter has a speed of about 1/15 second. Even if you don't have the "I" option on your shutter, you could probably get a speed possibly as fast as 1/8 second. To do this, deflate the bulb part way before squeezing, then work it as fast as you can. If the shutter is clean inside, you can get a pretty short speed with it. With practice you can get some consistency in the speed using it this way. I found that 1/4 second was easy to achieve with consistency, faster in a pinch. I also found that you could get some slight variance in the "I" speed by varying the force of the bulb-squeeze, but it's been so long since I worked out with this that I don't remember the details. I think it was on the order of magnitude of a difference between 1/10 sec. and 1/15 second. Rarely did I see a shutter that would go as fast as 1/20 sec. If you have a shutter tester you could work it out; if not, then testing back and forth with a regular lens/shutter combination and the Packard, developing your films together, you could probably work out what the speed is by noting the difference in negative or print density between the two shutters driving lenses open to the same stop, or even the same lens (using the same lens, you'd make exposures with its regular shutter, then open it up using the "T" or "B" setting and expose using the Packard). Hope this helps. 'Bye for now, --Michael Hendrickson [EMAIL PROTECTED] _______________________________________________ Cameramakers mailing list [EMAIL PROTECTED] http://rmp.opusis.com/mailman/listinfo/cameramakers
