THIS TYPE OF SET UP WAS MOST COMMON IN CINEMAS DURING THE 1950'S AND 60'S
Two projectors running 2000' spools (approx 18 minutes) , the average movie consisted of about 5 or 6 reels.
Film was loaded into the projectors with the film leader set on number 7 , each number segment on a film leader represented one second. When the first reel was almost finished , the projectionist would strike up the carbon arc on the second projector , get it burning right then go to the port hole and wait for the first cue mark ( a small white circle in the top right hand corner of the picture).
On the first cue mark the projectionist would start the projector motor running and open the lamphouse dowser , then wait for the second cue mark (seven seconds from the first mark) . On the second cue mark the projectionist would activate the changeover shutter on the projector and witch the sound pickup from projector one to projector two , The change over is complete.
The first projector is then shut down , reels removed and hand rewound on the bench. The next rell is then loaded into the projector and the arc rods adjusted in the clamps , as the arc rods burn away , positive rod more than the negative rod.
This projector is now ready for the next change over , and so the process continues through the session.
Arc rods generally always needed attention through out the sessions , they would never seems to burn evenly or feed evenly.
Next came the 6000 foot spools , three 2000' reels would be spliced together , heads and tails removed . This cut back the amount of change overs required , but did take up more time to prepare the program.
The two projector system then started to dissappear with the introduction of Eprad tables which ran 20,000 foot spools and then platter systems , a round flat table which the entire film would be joined ran from , automatically rewinding as it ran.
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