Originally posted by Anvh Since there is no way to test that i'm very curious how you can be so sure... Canon and Nikon camera's are often able to go slightly past that limit.
The reason for my certainty is because I know how shutter systems work. I work with Canon and Nikon cameras and I do notice a drop in the GN when full synch speed is being used, the difference between 1/180th and 1/250th is only really important when you are using focal lengths at or above 200mm.
Originally posted by maxfield_photo But for the sake of argument, lets say that the black bars begin appearing at 1/181st of a second, that still doesn't mean that they will occupy the entire frame at first.
Correct, the black bars will not be immediately visible. It is interesting to note that in practically all modern shutter units the shutter blades are only moving at roughly 7m/s which is around 25.2 Km/h (15.6Mp/h). The T.1* time of the Pentax AF540FGZ at 1:1 power
is said to be around T.1=1/400. So using this knowledge I'm sure someone could figure out how much of the frame would be black, as things stand the hour is too late for me to accomplish such a task at present. Burning the candle at both ends has its drawbacks.
*T.1 times are more relevant when one is trying to stop fast motion, The T.5 time for the AF540FGZ @ 1:1 power is
approximately 1/1200th.