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View Full Version : Roll filmback Q?-what about those...for?



Dongyun Hao
12-Dec-2000, 02:44
Just curious! This is actually applicable to RFBs of any format including those on some old 35mms. There are regularly knocked concave dots on the pressure plat e of RFBs. I wonder what they are made for? Why not being made into a glossy sur face? Is this something to do with film flatness? I would appreciate your knowle dge on this. Thanks!

Dongyun

Pete Andrews
12-Dec-2000, 05:36
I think the purpose is to provide small air pockets between the pressure-plate and the film. This reduces friction by lessening the contact area and preventing a partial vacuum forming under the film.

Doug Paramore
12-Dec-2000, 10:43
According to the folks in Florida, these are known as "dimpled chads" and are there to create confusion. Glad to be able to clear this up for you.

Regards,

John H. Henderson
12-Dec-2000, 12:31
Those of us in Florida need to count all those dimpled chads. Please inspect the pressure plates of all of your cameras. If you find those dimpled chads, please mail the cameras to me for counting.

Thanks for your help in ensuring a quick resolution.

John Brevard County, Florida