Sunday 8 July 2007

Eiki SL1 16 mm film projector

In the days before video players, the great multimedia educational resource around the world was, of course, 16 mm sound film. Just about every school in New Zealand had a projector of their own, often installed in a specially fitted out classroom with blackout curtains and a screen. These pictures are of an Eiki projector, which was probably the most common brand in NZ schools although there were others like Bell & Howell etc. When I started at High school, having gone through primary and intermediate watching films in the class, the school decided that we were responsible enough to become student projectionists, and so, with a handful of others, I got a projectionists' certification for Eikis.

The school had three of these as I recall, the oldest required a complete manual threading. The newer models at that time were automatically threaded, push a lever, turn the motor on, feed the film in and it would thread itself. This particular one you see in the pictures is "slot load" meaning the film is just slipped into the slot, then when the knob is turned on the sprockets drop into place and engage the film. You can't manually thread one of these at all whereas an auto threader can always be manually threaded.

Here's a view of the main controls. The big knob top right focuses the lens. The main control knob lower right turns on the motor and lamp. At lower left you have volume and tone controls. The small socket is for a microphone which allowed these units to be used as a small single channel PA with the external speakers, and I did occasionally see one used like this. The small toggle switch appears to be a local modification to select between the built in and external speakers. This particular projector has been fitted with XLR jacks for the speakers rather than the standard 1/4" jack which used switch contacts to cut out the internal speaker when plugged in,

This picture shows the front of the unit with the lamp housing cover removed. The projection lamp is inside the metal cover that says "Caution Hot". Below that can be seen various rollers, the black one to the left is the trailing sprocket. There is a leading sprocket near where the film enters the projector. In this picture also you can see the sound lamp. 16 mm film generally uses an optical soundtrack (although occasionally a magnetic strip is used) which works by shining light through the film onto a photoelectric detector.

At the right you can see the gate. The film moves in the gate by a claw which uses a shutter to block the light off before the film is moved one frame at a time. This conflicts with the continual rotation of the sprockets so the film's movement is buffered by the upper and lower loops which are respectively above and below the gate. It is imperative for the correct operation of the projector to maintain the size of these loops. One of the fun things of the projector was that if tbe bottom loop got too small there was a little arm that was tripped and would rotate one revolution to pull the film through the gate so as to make the lower loop the right size again. This invariably resulted in a jumping picture on the screen.

Inside the guts of the projector with the cover taken off.

A reel of film. Reels were generally five sizes, each being a successive multiple of 400 feet of film. The sizes were A, B, C, D and E - the last was not common. 400 feet of film will last about 12 minutes so the sizes ranged up to 1 hour. Sometimes a film would be on more than one reel. This reel seen here is a C and will hold up to 1200 feet when full.

Films were shipped out from the National Film Library's Christchurch office to schools around the city once a week. At high school they came in on a Tuesday afternoon. We had two projection rooms with their own projectors and in the senior school a third projector was used as needed or as a spare. The projection rooms each had a little room off the back where the projector was and where the projectionists sat and kept an eye on the machine. Once the film was finished it had to be rewound, turning a lever reversed the direction and made it go faster than it would go through the projector. Generally we got extra time out of class to get there a little ahead and thread the projector, then rewind the reels afterwards and lock up the room.

We also learned how to splice film together, which involved cutting the ends off square, scraping off the emulsion, applying a special cement to one end, overlapping the ends and pressing them together in a special tool, although you could get by without it just by lining up the sprocket holes. Films of course went around the country and got damaged. Torn sprocket holes were an example, these would cause the film to jump as the lower loop would usually shrink and trip the reset arm to pull the loop back to size. If this happened too much you had to stop the projector and rethread by pulling more film through from the top to reset the loops back to size. If the film snapped or tore it would have to be spliced which invariably meant cutting out the damaged part, a few frames at least.

Video did not take over until a few years after I left high school. The VCRs then available were very expensive and few titles were available on them. Most high schools would have had perhaps only one or two VCRs in specially equipped rooms due to the cost of them (four figures was common). A far cry from today when there might be one in almost every classroom. But once video did take over then film fell out of vogue, along with the need for the special theaterettes which were in most cases co