Platter Systems: Difference between revisions

One problem that is always present when plattering or building up to large reels is the need to cut the [[leader|head and tail]] off of each reel in order to join the reels together. To prevent the reel order from being mixed up after the print has been broken down, the first and last frame of picture were left on the head and tail respectively. This identifying frame (sometimes called a match frame) was then matched to the reel upon breakdown. If done properly, this results in a single splice (probably concealed by the changeover when run reel-to-reel) and no footage loss. In practice, however, it was common for projectionists to tear the tape splices between the reels by hand instead of peeling off the tape, causing damage to the frames. It was also common practice for each subsequent venue to simply make a fresh cut instead of reusing the existing head or tail splice. This resulted in cumulative footage loss, and often in a series of poorly made splices immediately adjacent to one another at the end of the reel. Heads and tails were often rejoined to the reel using masking tape instead of being properly spliced.

*'''Brain wraps''': Film can wrap around the centerfeed (commonly called the “brain”), preventing it from advancing. When a brain wrap occurs, the portion of the film engaged with the sprockets is mangled and the film in the gate will blister or burn unless the dowser is closed immediately. Brain wraps can be caused by disengaged feed platters, problems with the centerfeed, sticky film, tape left on the tail, and static built-up in polyester film.

*'''Film spills''': Platter systems are prone to two sorts of film spill. Most commonly, the takeup platter is not properly engaged and the film is fed through the projector and then spilled onto the floor. Without film break sensors in place, an entire print can spill out if the projector is unattended. Film can also spill off of the feed platter if the tail becomes loose. The tail cannot be secured with tape, which would cause a brain wrap, so it was generally just tucked underneath the print. If the projectionist forgets to tuck it in or it comes loose during playback, it can slip off the edge of the platter and cause a cascading film spill.

*'''Endless loop systems''': While primarily used for specialized installations such as museum exhibits, endless loop platters were popular in multiplexes for a brief period. These systems have a number of issues, including the fact that the film accumulates dirt more quickly because the projector cannot be properly cleaned. Film run through an endless loop also eventually develops mottling from repeated film-on-film contact, and some models have swinging guide arms that scratch the film. The many issues associated with endless loops were exacerbated by the transition to polyester film in the 1990s. Polyester is susceptible to static cling unless the temperature and humidity of the booth were carefully maintained, and this can prevent the film from feeding correctly. While this is an issue with all platter systems, it is especially problematic for endless loops, which require the film to be loosely packed.

For these reasons, platter systems remain an acceptable transport method for newly struck [[70mm]] prints. With the revival of 70mm as a prestige format in the 2010s, a new print assembly workflow was developed for platter houses. For the 70mm releases of Hateful Eight and Dunkirk, the onus of cleanly assembling the prints was taken off of the individual projectionist. Instead, Boston Light & Sound created a “platter farm” where the 1000’ reels were preassembled using ultrasonic splicers and shipped on modular platter reels to each venue.^[1][2]