I am having exposure problems, especially at slow shutter speeds. I generally am looking for maximum depth of field, so that means slow shutter speeds. I've done exposure tests on transparancies (because of its low tolerance of latitude) on a chip chart, but come out with very dark transparencies. <p> Are my tests flawed? For example, 1/50 looks good when I set my recalibrated meter at 1/12, but on a shoot they were significantly underexposed at 1/12. <p> Will a shutter speed give different speeds at different times? I am at a loss. <p> Both my lenses, Graflex Optar 127mm and Graflex Optar 203mm have the same problem at the slower shutter speeds. If I could stop down to f/64, then maybe I could use a stop watch and use exposures in the seconds (ha!). <p> Any help would be appreciated.