American cinematographer. (1943)

completed and may be removed from the splicer. The whole operation is very simple. If a little water is applied to the end that is to be scraped, it will be found that the emulsion may be re¬ moved easier, though perhaps not so neatly. Here it might be stressed that all of the emulsion must be removed from the area covered by the scraper if the splice is to hold permanently. It is also a good idea to roughen the film base after the emulsion has been removed so that the welding action of the film-cement will be better. The registration pins of the splicer will hold the film in correct registration during these operations so that the splice will be perfect. After the splice has been removed from the splicer, test it to make sure that it won’t come apart, by twisting it slightly. Bad splices will come apart during projection and may cause film damage. These bad splices are caused by: (1) the emulsion not being thorough¬ ly scraped off; (2) an insufficient amount of cement being put into the splice; (3) too much cement on the splice which will dissolve the film base and make the film weak and brittle at this point; and (4) old cement which has lost its welding- power or will cause the film to become stiff, hard, and buckle on projection— usually breaking between the sprockets. Use only good, fresh film-cement and keep the cover on tight at all times when not using it. On sound-films, whenever a splice passes through the sound gate, you may have noticed a sudden pop or blurp from the loudspeaker. This is caused by the sudden interruption of the sound-track by the splice. It may be avoided if, at the time of making the splice, a wide “V”, with its legs spread far apart, is made across the sound-track area of the splice with black water-color paint or other opaque material that will not read¬ ily rub off. You can get special paint for this, known as “blooping paint” from most theatre-supply stores. This “V” will serve to extinguish the track gradually and thus eliminate the sudden, objec¬ tionable pop. As was mentioned earlier, motion pic¬ ture film should be kept in dustproof containers at all times. Immediately after the film has been projected it should be returned to its can and covered—and then as soon after¬ wards as possible it should be rewound onto the original reel, ready for the next projection. In rewinding your film, do not rewind it too tightly. On the other hand, do not rewind it too loosely, as this will allow it to shake in folds in the can and cause frictional wear during transportation and projection. Maintain a fairly even pressure on the rewind brake or supply reel when winding onto the take-up reel. This will assure the film being wound smoothly and with an even-tensioned flow, and will keep the dust from settling into it when the cover is off the container previous to loading and unloading the projector. If your film has been wound too loosely on its reel, rewind it again: never take it by its end and pull it tight. If you do, this will cause bad scratch-marks known as “cinch marks” on the film. Stoi-e your films in a cool dry place. This is especially important with Koda- chrome or color films which are readily attacked both by excess moisture and heat, resulting in the emulsion blistering and the colors fading. Do not at any time allow your films to be kept near a source of heat such as a furnace, a radia¬ tor, hot-air register, steam pipes, etc. To do so will cause the film to shrink so badly that it will be impossible to pro¬ ject it. In hot weather, do not leave your films in a closed automobile—the temperature will build up amazingly and may ruin your film if the car is left in the sun for any length of time. Black-and-white film which has been stored for a long period of time where it is very dry is liable to become quite brit¬ tle and break repeatedly on projection because of loss of its moisture content. This happens quite frequently in office- buildings heated by steam radiators, where the air is liable to be very, very dry. If this is the case, the film should be humidified before use. In the bottom of most film cans is a small blotter, covered by perforated metal or wire mesh. This should be dampened and the film stored in the closed can for from twenty-four hours to three days. Do not allow any water to touch the film as it will mildew and be ruined. If the films have to be stored in an excessively drj place where they are liable to dry out, moisten the humidification-pads or blot¬ ters every four to six months depending A uricon SOUND CAMERA for 16 mm sound - on -film MANUFACTURERS OF SOUND-ON-FILM RECORDING EQUIPMENT SINCE 1931 ACME OPTICAL PRINTERS (35mm.— 16mm.) We are now going into production with the first optical printer designed throughout as a single, coordinated unit. Printer-head has automatic take-ups (1000-ft. capacity), Bell & Howell Type pilot-pin movement, and is interchangeable with 16mm. head. Camera-head is an integral part of printer, Bell & Howell type movement, 170-degree shutter and Mitchell magazines, with instantaneous visual focusing and provision for registering of line-up film. Camera-base provides for magnified and zoom shots. F:4.5 four-inch anastigmat lens, specially corrected and mounted with lateral, side and cross movements. Illumination from 1000-Watt diffused projection-lamp, interchangeable with other types as necessary. Operating speeds 10, 20, 30 and 60 ft. per min., with reverse for fast rewinding and reverse printing Available on Priority or Lend-Lease ACME TOOL & MFG. CO. 2815 W. OLIVE AVENUE BURBANK, CALIFORNIA American Cinematographer • May, 1943 195