Visual sound patterns

Currently i’m working, experimenting, on sound-on-film technique used in (among others) 16mm film.

First I took photo’s of the beautiful mosaics in La Grande Mosquée de Paris. The mosaics often used in Mosques have so many patterns in them that want to be sounds, so I decided to try to make that happen.

Electronic sound is created by fast changing voltage pulses. By changing the frequency and the voltage of  the pulses, the tone of sound changes into e.g. music. In sound-on-film an extra step is added. A small stroke on the side of the frame contains the sound wave forms. Those wave forms look similar in sound or video editing programs on your PC, where this is a representation of the pulses that are send to the sound card and later to the speakers. In film a light sensor is used to do that same trick. The light sensor continuously translates the difference between black and white (actually black and transparent) into a voltage pulse, and then by a speaker into sound.

In Visual Sound Patterns I want to make my own sound-on-film patterns. I use the photo’s I made of the mosaics and distill my own sound patterns out of it. After drawing it it will be laser cut on black card board. In the dark room I will use this ‘mask’ on a strip of film. After exposing the film the masked parts will be transparent and the non-masked parted black.

Simple film to sound device

To test the sound-on-film-strips I will be making for my new project “Visual Sound Patterns”, I made a testing device. I used a piece of film from another project since it has alternating black and transparant frames, which will work to create some sound.
In the end the best way seemed to replace the hand crank I made earlier with a drill, but it works..

Old 16mm projector technics

I had the honour to meet Laurent Mannoni in his warehouse full of ancient film projectors and camera’s at  La Cinémathèque française. I wanted to learn how the first film projectors worked. To find what way would be best to eventually build a DIY 16mm LED projector, which would be easy enough to reproduce for others.

One of the complexities of a projector is how to make a frame on the film stand still for a moment, and later be transported to show the next frame in still position, and so on. This 24 times per second. I learned that, in the early days of film, there where mainly three ways to make the frame stand still for that short moment.

The Maltese Cross is the technique that is still used in common 16mm projectors. It’s the most robust way of moving the frame, but also the most complicated to build. In this video you can see the maltese cross in a 16mm hand crank projector. Normally the cross is inside a box with oil so it doesn’t wear out.

The Bouly Movement was used on some 35mm projectors. A thick soft material is attached on a wheel that only transports the fed through film. Thus by pressure.  It was not used for long, even though at the same time it should still work quite well. On 16mm film though the part’s might get to small to make it work.

At last there was the Dog Movement. A little bend pol would push the film one frame further, as shown in this video.

The shutter is a plate, or a mask, that blocks the lens of the projector from light coming through at the moment the film is actually transported. Like the big aluminum plate in the above video. This photo shows why these days this masking plate is build in the projector itself. Imagine the metal platter spinning 24 times per second..