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1952 Theatre Catalog, 10th Edition, Page 296 (260)

1952 Theatre Catalog, 10th Edition
1952 Theatre Catalog
1952 Theatre Catalog, 10th Edition, Page 296
Page 296

1952 Theatre Catalog, 10th Edition, Page 296

FIG. 13. Conventional threading for lower loop.

highly polished metal surfaces are scratched.

New Print Mounting

It is important to note that the emulsion surface of newly processed film is more susceptable to abrasion than film which has seen service. Therefore, in mounting new prints just received from the laboratory, care should be taken to avoid Contact with the picture area even though cotton gloves or a cloth might be used. New film should not require cleaning but if it is found necessary to remove lint or dust particles such as might come from the tissue wrappings or cardboard separators, silk plush, slightly dampened with carbon tetrachloride or other film cleaning liquid,

FIG. 14.. Accumulation of hardened gelatin on tracks near the aperture.

should be held very lightly against the film as it is wound. The plush pad surface should be changed frequently and the surface of the film should be checked often for any abrasions which might result from this "dustingi, process. Winding should be carried out very slowly to permit complete evaporation of the solvent, otherwise the latter may cause spotting of the film if it is wound into the roll. If carbon tetrachloride is used, ample fresh air ventilation is essential


in order to prevent toxic effects resulting from undue exposure to the fumes from this chemical. Carbon tetrachloride fumes are poisonous; headache and nausea are a first warning, and continued exposure may be fatal. Evaporation of only two teaspoonfuls of carbon tetrachloride into a small unventilated film inspection room is enough to raise the concentration of fumes beyond the safe level. Carbon tetrachloride is dangerous whenever the odor becomes strong enough to be obvious. Ventilation must be good so that a person just entering the room where carbon tetrachloride is being used can barely smell the fumes. If the fumes become stronger, all windows should be opened, the cleaning stopped, and the room emptied until it has been thoroughly ventilated.

Protective Leaders and Trailers

Protective leader and trailer strips should be kept at full length. Motor winding speeds are frequently so high as to cause the end of the film to whip around (on the projector take-up as Well as on a motor-drive rewind) a number of times before the roll is stopped. This can be responsible for considerable loss in footage if the protective leaders or trailers are allowed to become too short.

Print Circuiting

In locations where a shortage of prints exists it is often necessary to circuit them directly from one theatre to an H

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FIG. 15. Guide rollers.

other. In such cases, release prints frequently suffer considerable damage. There are recorded instances of some prints being exhibited by six or eight theatres before they are returned to the exchange for examination and repair. It is quite possible that some types of damage which occurred during projection or handling by the first few theatres might have been arrested. Instead, further footage is affected and the total damage is more than it need have been, if caught in time. Circuiting also makes it impossible to identify the theatre responsible for the damage in the event that compensation is sought by the exchange.

Guide Rollers

The guide rollers located above the gate or trap (Figure 16) serve as a guide for the film as it passes down past the aperture to the intermittent sprocket. If these rollers are out of line with the sprocket, the teeth will engage the film perforations off center, and the sides of the perforations may often become broken. Also, if the rollers do not turn freely, they will eventually develop

FIG. 15. Damaged perforations caused by intermittent sprocket as a result of excessive accumulation of gelatin at the aperture.


1952 Theatre Catalog, 10th Edition, Page 296