Century-old equipment used to fix modern deterioration problems: Shrunk film leader and its use in sound preservation
The custom mag machines at Endpoint are capable of extremely low wow/flutter even with severely deteriorated, shrunk, and warped film. However, no continuously moving machine can work perfectly with massive shrinkage changes at hard audio edits (when the recorded program touches the splice). The inertia of the system needs at least a fraction of a second to readjust and fully settle at hard jumps in shrinkage. This is typically an issue at the very head of the film when the original leader has deteriorated beyond use, or has been replaced with newer leader.
A shrinkage jump at the head of a reel can be found in composite masters, but it is especially a problem with music cues or production elements that were broken out of units for future use. Often the downbeat of the music cue is right at the edit point. An example of cut 35mm music cues are shown above. In situations where there are less than a few frames of buffer at a drastic shrinkage change, the transition must be dealt with to avoid severe wow as the speed settles.
The simplest and most effective way to deal with this is to use “shrunk” leader instead of new leader. The shrinkage of the leader can be matched roughly to the shrinkage of the film it will follow. For example, if the film is shrunk 4%, then the leader is best when it is also shrunk 4%. Although this seems like a fairly simple solution, most film perforating machines even going back 1910 are too precise and sophisticated to easily allow a non-standard film pitch. In fact, the precision of the Bell and Howell perforator developed in 1910 revolutionized the industry and continues to be used today. The accuracy achieved in their design is possible by punching four rows at once while the previous four punched rows are registered with additional pins. A full eight rows of perfs are present on the precision die plate.
Shrunk leader requires a pre-1910 machine used in an earlier era before film standards when each camera company supplied specific film pitches to customers. Following is a video of our turn-of-the-century Newman and Sinclair perforator that punches just one row at a time and is designed for continuously adjustable perf pitch. The film pitch is measured with digital calipers and dialed in to the desired amount of shrinkage. Creating the shrunk leader is a slow process, but typically only a short length is needed and is reused for multiple projects.