Film winders and winding
To examine, repair or treat film it is important to be able to keep control of the reel and prevent the film from coming into contact with dirt and potentially abrasive surfaces.
The most common method of handling film is to use a set of film winders. And if the film has been stored on a core rather than a reel then plates are also needed to hold the film reel in shape as it is being wound.
Film winders fall into two broad categories. In one, the circular disc against which the film is wound is horizontal, or slightly slanted, like a gramophone turntable, Fig 10.8 i). In the other it is vertical like a vehicle wheel Fig 10.8 ii). Regardless of whether horizontal of vertical winders are used the handles must be counter balanced. Counter balanced handles provide a more even tension to the films wind and allow you to stop winding at any point without gravity pulling down the handles.
Some films are received loosely wound (sometimes of necessity because they are damaged and cannot be wound tightly). In this case, gravity pulls the whole reel down onto the turntable, and the film is less likely to fall of the reel. All the film is near the surface of the winding bench and is easier to manoeuvre.
Most horizontal winders have a low gear ratio between the winding handle and the turntable (commonly 2:1). This gives better control over the wind. Vertical winders are usually geared higher (Commonly only 3:1 or 4:1).
The angle of the wrist and arm required by the horizontal winder also places less physical strain on the operator, compared to that of the vertical winder. However, since the film is further away from the operator there is a tendency to hold a bent over posture for extended periods while examining a film. This can lead to back strain injuries.
Some operators find it easier to look down through the film, with the plane of the film horizontal rather than slanted.
If it is necessary to wind more than one film (as in synchronising), the vertical arrangement is easier to use as it has a long spindle on which two or more reels of film can be mounted simultaneously.
Film repair is more easily performed on a vertical winder as the slant of the horizontal winder bench can make it difficult to keep the repair equipment in place.
Plates and springlocks
To hold the film in place on the winders and to ensure that the film lies evenly on the core, plates are used. Springlocks hold the plates in place during winding.
The plates used for any film should be specific to the film gauge (35mm or 16mm) and to the diameter of the film pack, i.e. 1000 foot plates for films up to 1000 feet long, 2000 foot plates for films between 1000-2000 feet. If the plates are too small the film can spill over the top (Fig 10.10) and become tangled around the winder, causing severe damage. If the plates are too large it can be awkward attaching or removing the adhesive tapes holding the leader.
For shrunken film it can be useful to have the plates hub slightly modified so that the core fits precisely between the plates. Normally there are a couple of millimeters clearance to prevent the film from catching on the edge of the plate. By modifying the hub the buckled film is more restricted in moving around during winding and a more even wind will result.
It is essential that you remain in complete control of the film at all times. At any time you must be able to stop without the film going everywhere. Always be aware of your winding speed, the angle of film and tension. If the film has no protective leaders at the head and tail then leader should be taped on before examining or winding. The tape should only be applied to the base of the film, never to the emulsion.
The alignment of vertical winders is important. The winders should be initially set up so that the plates are in line. Then the right hand winder should be move about 1-2° clockwise. It is convention to wind film from left to right. If you normally wind from right to left then the left hand winder should be the one adjusted by a similar amount in the anticlockwise direction.
Canting the winder provides a gentle edge to wind the film against. This provides a more even wind with no leafing (layers of film sitting above the film pack and highly susceptible to damage). If the winders are angled too far then the film will twist against the plate and the additional pressure may damage the film.
Winding problem film
If the film is sticky (e.g. from ferrotyping or decomposition) or very brittle, it should be wound slowly and with less tension. This helps to minimise the potential for further loss of emulsion.
If there is a slight tearing or ripping sound while winding stop immediately and examine the film. The film may be blocked and by continuing winding damage will occur to the emulsion.
If the adhesion is only very slight then a small piece of non-abrasive material — such as a piece of folded cardboard or ideally a thin strip of teflon — held at the point where the film lifts away from the pack will help to free the adhesion as the film is unwound very slowly.