Cleaning equipment

Equipment used to clean motion picture film prior to use or storage. Many machines are available and different machines use a number of methods and materials. The usual machines in use in a laboratory or archive are:

Ultrasonic agitation

The supreme virtue of this is that no solid surface touches the picture area of the film at all and it is thus virtually immune from causing any scratch or abrasion. It works by agitating the solvent fluid, through which the film passes, at a very high frequency, thus loosening dirt from the surfaces. It is quite effective except with badly ingrained dirt.

Lipsner Smith are a well known manufacture of these style of machines.

Rotating hair brushes

This involves the tips of the hairs brushing the film surfaces and is thus not immune from causing fine abrasions. However, it does seem to be more effective with ingrained dirt such as is found on older much used films. Such films often have their emulsion surface hardened by time and need not suffer significantly. The brushes may be immersed in the fluid and brush the film immediately it leaves, while it is still thoroughly wet. Dirt tends to migrate either away into the fluid or to the roots of the hairs.

Rotating velvet buffs

These perform in a similar fashion to the rotating hair brushes but with a little more risk of abrasion.

Rotating chamois or cloth buffs

Caution is advised because whereas with brushes or velvet only the tips of hairs need touch the film and any dirt is drawn away from the film, with cloth or chamois the dirt can accumulate on the surface of the cloth and possibly scratch the film surface.

Fixed rubber squeegees

Brown says it seems to be so easy for particles of dirt to lodge on the lips of the squeegees and abrade the film that these cannot be recommended.¹

Particle Transfer Rollers PTR

Machine built to clean film with Kodak PTR rollers. The film is never wet.

Rollers are washed and dried in detergent before use. These rollers can be fitted to printing machines and telecine machines to remove dust before the image is transferred.