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A proper lens takes the light coming from the object (the film in this case) and projects it in a way such that all light coming from a single point, whatever its direction of travel, will end up at a single point on the image (the fabric). Assumed is that the system is correctly focused. Wandering of the sun does not change this; a single point on the source will be projected to a single point in the image throughout the wandering of the sun. However, there is a different trouble; rather quickly the sunlight through a given point will not hit the lens so that point in the image will go dark. The nicest solution is what I believe is called a heliostat. This has a mirror which tracks the sun's motion in a way so the light is cast in the direction of the lens a the sun wanders through the sky. You could do it by hand until you determine whether making a real tracking machine is worth the bother. Please note, the sunlight comes from a constant direction when this device is in use, no matter where the sun actually is (if not below the horizon or behind a cloud!) There is a different problem as well. You more or less need a condenser unless the lens is bigger than the film. Sunlight travels as a nearly parallel bundle of rays. Only light passing through a circle the size of the lens but lying in the plane of the negative actually passes through the lens. You can move this circle over the film but only this much negative is being exposed at any time. Without a condenser you will have to "scan" the film by passing the light from various directions through the lens so the whole film is roughly equally sampled. I suggest adding apiece of heat absorbing glass if you can find one in the right size; for a 2x2 negative it should be relatively easy. Bigger will be harder and more expensive. Bob At 08:49 09.08.02 -0700, you wrote: > > Another thought... If you are exposing for a long period of time the > >position of the sun may play a huge factor on your enlargement with out a > >condenser..... Take a flash light and move it 25 degrees across film and see > >what it does to the final image on the wall... A guess would be that the > >image will move right along with the light thus ruining your print... John > > >I thought about that, but there would be a piece of diffused glass >between the sun and neg. >_______________________________________________ >Cameramakers mailing list >[EMAIL PROTECTED] >http://rmp.opusis.com/mailman/listinfo/cameramakers _______________________________________________ Cameramakers mailing list [EMAIL PROTECTED] http://rmp.opusis.com/mailman/listinfo/cameramakers
