Cine Film Format Explained
9.5 mm film is an amateur film format that was introduced by Pathé
Frères in 1922 as part of the Pathé amateur film system.
It became very popular in Europe over the next few decades. Over 300,000 projectors were produced and sold mainly in France and England, and many commercial features were available in the format.
The format uses a single, central perforation (sprocket hole) between each pair of frames.
The single hole allowed more of the film to be used for the actual image and in fact the image area is almost the same size as 16 mm film! The perforation in the film is invisible to viewers as the intermittent shutter blanks off the light as the film gets pulled through the gate to the next frame. In most 9.5 mm projectors, the shutter also operated once whilst each frame was stationary in the gate for the purposes of increasing the apparent frame rate.
Not many people appreciate that the width of 9.5 millimeters was chosen because 3 strips of film could be made from one strip of 35 mm film. This was useful when duplicating films because only 1 strip of 35 mm had to be processed. Finally, the sides, which contained the 35 mm sprocket holes, were cut off, the remaining film was cut into 3 strips, and the central sprocket holes added to each new strip.
9.5 mm film
the war, the 9.5mm gauge suffered intense competition from Kodak's 8mm
film, which was inroduced in 1936. Notwithstanding the poorer resolution
of the 8mm frame, which could hold only about a quarter of the information
of the 9.5mm or 16mm frame, 8mm was taken up by a wider public and the
wonderful name of Pathé began it’s decent.