Archived posting to the Leica Users Group, 1999/01/08
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]>I'm no expert, but here's my theory. A few weeks ago, I found grossly >underexposed >strips on my slides and the shop said the 1/1000 and 1/500 speeds weren't >working >properly. I don't know the technical terms, but not all the frame got exposed >the >same amount. Why don't you try having the shutter speeds examined by a shop. > >Alternately, you could maybe hold the lens up to a light, open the baseplate >and the back and try the speeds and see if you can see anything. > I believe the term is "tapering" -- when the opening and closing curtains travel at different velocities and thus there is a progressive increase or decrease in exposure as the shutter "slit" widens or narrows at it moves accross the film gate. Is most pronounced at high speeds. At 1/1000th the shutter slit is only a few millimeters wide and therefore different velocities of the 2 curtains is more noticable. I don't believe just holding a shutter up to light will help. There is the old TV trick for speeds faster than 1/60th of a second -- but this does'nt help diagnose tapering I don't believe ( Sherry could fill us in on this ). Need a real shutter speed tester that tests shutter speeds at several different locations along the path of travel. Mark Hammons