Quote Originally Posted by Newt_on_Swings View Post
It has a slightly different sprocket hole pattern, with rounded sides to accommodate the high speeds inside motion picture cameras.
There are several perforations used in the 35mm cine world. And two types of holes. But the difference is not due to the speed of film as for instance the film speed is basically the same in the camera and in the projector. The reason for one part are other technical factors and, probably more important, to many people gathering at too many conferences...