Does anybody know the length of time it takes the focal curtain to travel across the image in a Speed Graphic? If I set my time at 1/1000, what is the length o f time that will elapse from the moment the curtain slot leaves the top of the c amera to the moment it closes completely at the bottom? I am trying to get aeri al images as sharp as possible and I am wondering if a Speed Graphic at 1/1000 w ill produce a sharper image than a lens at 1/500 while in a tiny airplane travel ling 100 mph and shaking all over the place. But perhaps the lens (which shoots no faster than 1/500) would provide the sharper image, as the shutter curtain w ill take some time to travel the whole distance and in that time my camera will be in a (perhaps significantly) new position relative to the subject. Earlier s hots made with the lens shutter were not all that great, which is why the musing about a speed graphic. I cannot afford a new lens with a shutter speed of 1/10 00.