Hello Everyone- I'd like to try my hand at building a camera for meteor photography. I have a surplus 6 inch Metrogon lens mounted in the original 6 inch diameter diaphragm/shutter assembly; my lens came with the original yellow filter. I plan to build the camera from oak in the shape of simple flat box with the lens permanently mounted on one side of the box with the focus at infinity. I'll be using 8x10 sheet film in regular sheet film holders.
I hoping that someone can provide some advice on this project. I'm an experienced amateur photographer and have a woodworking and metal shop. (1) The lens has a six inch focal length. I believe that I'll need to have the optical center of the lens this distance from the film plane (actually 151.3mm according to the engraved value on the lens ring). I'm not certain where the optical center of this lens is located within the lens barrel. Is the optical center equidistant from outer face of the front and rear lens elements? Is the diaphragm located at the optical center in this lens design? The unambiguous way to determine the correct focus, of course, will be to bring the image into focus on the groundglass which I'll be including in the camera. I'm hoping to get a rough idea of the flange to film distance needed here for help in designing the camera, prior to beginning construction. I'd like to make the film to flange distance slightly under length then bring the lens into focus with shims. (2) I haven't opened up the lens mount at this point. There are a pair of electrical leads coming out of the back of the mount; I presume these were to actuate an electrical shutter. I found the resistance between these leads to indicate an open circuit. I'll have to venture into the mount to find out what these leads are, and if there is a shutter there, and attempt to repair it. What was the actuating voltage for shutter used with these lenses? Much aircraft equipment uses 24 volts DC; I thought that this might be the case here as well. If I can't use the shutter (if any) that came with this lens, I'll either use a simple lens cover to time exposures or mount a large Packard as a front shutter. Thanks in advance. Ed Balko _______________________________________________ Cameramakers mailing list [EMAIL PROTECTED] http://rmp.opusis.com/mailman/listinfo/cameramakers
