If you want to get really cheap, Harbor Freight Tools sells a aluminum bar clamp that's 36 inches long, and wouldn't take much to make into a monorail for a camera. It costs about 6 bucks on sale, which I believe it is until Dec. 2. It has a plain spring latch lock on one end, and another with a screw clamp on the other end. You'd have to figure out a way to attach the standards, and to add a tripod mount, but that really shouldnt be hard. Use the spring latch for coarse adjustment and the screw part for fine adjustments. It's not as rigid as I would wish, but for that price it's really not bad.
Gene Gene ----- Original Message ----- From: "Ter McDonagh" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Sunday, November 24, 2002 10:19 AM Subject: [Cameramakers] Method of focusing > > > > Howdy folks, > I'm new to the forum, but have "lurked" for a couple months. I just > obtained a 16" Cooke Process Anastigmat. Unfortunately, none of my cameras > have that much bellows. I'm thinking of building a very basic box (maybe > 3/8 plywood)about 15 1/2" long (by 5"x5"), and already have a spare 4x5 > spring-back. I don't plan to have any lensboard movements on the first > prototype, and maybe a little front rise later on, and want to focus from > infinity down to around 15-20 feet. I will be mounting it to a tripod, but > wood still like it to be light enough to hike with. My question is, what do > I do for front focusing, keeping in mind that the lens is about 2 1/2" in > diameter and weighs about 4 pounds? Do I mount a sort of monorail on the > bottom (or top) of the box and put the lensboard on a standard, and fit a > square bellow between the standard and box? Is there a simple type of > helical focus I can make that will be tight enough not to "unfocus" when I > close down the aperture? Do I just use two bolts (or four) and use shims > for some preset focus distances, and if so, how do I do it so they're > light-tight? Also, is there an easy formula to figure out how much "throw" > I need to focus from infinity down to my goal of 15-20'? Thanks for any > help. > > > _________________________________________________________________ > MSN 8 helps eliminate e-mail viruses. Get 2 months FREE*. > http://join.msn.com/?page=features/virus > > _______________________________________________ > Cameramakers mailing list > [EMAIL PROTECTED] > http://rmp.opusis.com/mailman/listinfo/cameramakers _______________________________________________ Cameramakers mailing list [EMAIL PROTECTED] http://rmp.opusis.com/mailman/listinfo/cameramakers
