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Program National Film Preservation Board

Film Projection Guidelines

Handling and Projecting 35mm Archive and Studio Prints: Voluntary Guidelines
Supporting Document B: Public Access and Educational Use Task Force

(published August 1994)

The continued availability of older American films for public exhibition depends on proper care of existing 35mm prints. Archive and studio prints (sometimes known as vault prints), unlike distribution copies, are produced in small quantities for internal use. Often a title is represented by a single 35mm print made from preservation materials or surviving from the original year of release. Additional copies can be difficult and expensive to make. Thus archives and studios lend only to exhibitors willing to take special care in handling and projecting these fragile materials.

The Public Access and Educational Use Task Force, appointed by the Librarian of Congress to advise on the national film preservation program, has developed the following voluntary guidelines to assist exhibitors, archives and studios in framing acceptable practices for handling and projecting rare 35mm archive and studio prints. These voluntary guidelines draw upon the experience of archive and studio projectionists. They are presented as an informal reminder list for the practicing projectionist.

Preparing Projection Equipment for Use

1. Inspect equipment for dirt and dust, particularly at all contact points along the film path and at any optical or magnetic scanning points.

2. Check the mechanical alignment to insure that the film runs through the projector in a straight path and is not skewed.

3. Check film tension. Under normal operating conditions film tension should be between 6 and 16 ounce-feet (oz-ft). Because film and sprocket tooth combinations tear when the tension exceeds the uppermost limit of 15 pound feet (lb-ft), the tension of all film handling equipment should be far below this level. Tension as low as 6 oz-ft is sufficient to provide a steady screen image. Tension greater than 16 oz-ft accelerates film wear.

To measure film tension in the feed or take-up system, place the equipment in its normal operating mode. Circle about 3 to 6 feet of film around the hub of the reel, attaching the other end to a dynamometer.

To measure the tension necessary to move the film through the projector gate, place a short length of normal print material in the projector gate and close the gate. Attaching the film to a dynamometer, pull the film through the gate.

Test and adjust rewind equipment to meet the same tension specifications.

4. Provide an adequate supply of undamaged take-up reels. Take-up reels should be free from burrs and other defects, properly aligned and seated on their spindles, and of the largest practical hub diameter. The hub diameter should always be at least 4 inches.

Storing and Handling Prints

1. To create a spotless projected image, good housekeeping in the projection area is essential. Clean frequently any equipment or surface that may come in contact with the film. Select new, perfect reels for storage. House prints so that they will be free of dust.

2. Take-up reels on reel-to-reel machines should be cleaned at the start of each day to remove dust and debris, and checked for dirt at the end of each show.

3. Before screening, inspect the print for physical damage, handling the film itself as little as possible. When handling is necessary, hold film by its edges. During thread-up, handle only the leader and keep finger contact to a minimum. Never allow the film to touch the floor.

4. Whenever possible, film should be handled in a work area provided with positive pressure and with a filtered, temperature- and humidity- controlled air supply.

5. Clean film only where necessary. Use a commercially available film cleaner. Generally cleaning and lubrication should be done at the laboratory.

Projecting

Film prints should be shipped with an instruction sheet listing the correct aspect ratio, projection speed for silent films, special handling requirements, and name of the person to call should questions arise about the print.

Archive and studio prints should be shown only by a qualified projectionist, who remains in the booth throughout the screening. Accidents do happen, even with the most sophisticated equipment. Should film damage occur, do not mend the film yourself unless repairs are required for the screening. It is essential to notify the lender of damage when the print is returned. Lenders should include with the print a form on which projectionists can note the condition of the print, as received, and report any new damage.

1. Check that the projector is fitted with an aperture plate and lens appropriate to the film's aspect ratio.

2. Set lamphouse output for proper screen brightness. The brightness recommended by SMPTE is 16 foot lamberts (FL) in the center and no less that 12 FL at the sides. If the lamphouse is properly adjusted and installed, light will not damage the film.

3. Run a black, opaque 35mm film loop through the projector to test for scratching.

4. Adjust gate pressure to the "minimum setting" to eliminate jitter and to achieve a steady picture.

5. Adjust take-up and hold-back tension to the least amount necessary for proper film handling.

6. Before loading the film, check all guide rollers for dirt, flat spots, and smooth rotation. Check the focus using the SMPTE test film.

7. When threading the film, set the loop sizes according to the specifications particular to the projector type. Be sure to keep the loops small enough so that they do not slap against the machine. Also, be sure the loops are the right size for the synchronization of picture and sound.

8. Clean the gate frequently. At the end of each show, check for dirt and clean as necessary. Clean the lens as necessary.

9. Unless specifically negotiated with the lender, do not use a platter projection system. With platter systems, the head and tail leader of each reel of film must be removed. Platter systems also have more guides and therefore are more likely to damage film.

Drafted by the Public Access and Educational Use Task Force: John Belton (Rutgers University), David W. Packard (Stanford Theatre Foundation), Richard Prelinger (Prelinger Associates/Home Box Office), Eddie Richmond (UCLA Film and Television Archive), Karan Sheldon (Northeast Historic Film), James Watters (Universal City Studios), George Stevens, Jr. (independent producer).

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