Le 10.6.2002 22:32, « Penne, Phil » <PenneP@hsn.net> a écrit : > Anyone got a slick do-it-yourself way to check shutter speed accuracy on a > camera? I seem to remember there was one method that involved photographing a > TV screen and counting the number of scan lines at any given number shutter > speed. Another method involved photographing a phonograph turntable (alright, > alright, I'm old - I'll admit it. At least I didn't say, "Victrola"...) at > various shutter speeds and measuring the angle of blur. > > Any other novel ideas? > > Phil Penne > > You go out on a sunny day, you point your camera at a patch of pure blue sky, preferably aiming in the opposite direction of the sun, you take a reading of the light and set the largest aperture and the speed according to the reading you have made. Say you are shooting with a 100 ASA, then you set the aperture at F16 and the speed at 1/125; that would be the first shot.. Then you set F11 and 1/250 and then F8 and 1/500 and so one. On the opposite, you'd have F22 1/60 and F27 1/30. You can add neutral grey filters if you want to test for the slower shutter speeds; if the speed of the shutter is consistent, then you'll get pretty identical shots, or at least the difference shouldn't be higher than 1/3 of a stop.. I read that test in Popular Photography once; the test will also show you whether some vignetting occurs with your lens and shade..
