F. and S. Marriott 140 Newbegin, Hornsea, England, HU18 1PB

May 2010. Stephanie died peacefully on 19th April after a short stay in hospital. She had been suffering from acute cervical cancer. Fred will continue to run the business to the best of his ability. The web site is slowly getting under control again as he tries to take over some of Stephanie's responsibilities, and learns some of the mysteries of Dreamweaver.

Pieces An on-line look at cameras etc. by Stephanie Marriott

Introduction

Methods

Cement

Tape

Recipe

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November 2002 - Splicing Cine Films

Any user of cine film is at some stage faced with the problem of joining two piece of cine film together.

We have successfully overcome a film breakage while showing a film by sticking the two pieces of film together with ordinary self-adhesive tape. This is strictly an emergency measure however, for film which has passed through the projection gate, performed to allow the film show to proceed. The splice, not having been aligned properly, will almost certainly not pass through a gate. The tape will not be perforated and the adhesive is not heat resistant, so may ooze out. Any film join made with ordinary adhesive tape should be replaced by a proper splice as soon as possible.

There are two basic methods of splicing cine film:-

(a) a solvent which "melts" the film base is used to "weld" the two pieces of film together.

(b) a specially designed self-adhesive tape patch is used to join the two pieces of film

Each of these methods has its advantages and disavantages. There is no perfect solution. Sometimes one method or the other has to be used - for example, if preparing film for copying to video, ask the company who will be doing the copying whether they have a preference for tape or cement splices.

Whether you choose tape or cement, practice on some old film until you are comfortable with the procedure.

The aim of a splice is to be as unobtrusive as possible when the film is shown. The splice must be flexible and strong enough to not break whilst the film is undergoing the pushing, pulling and sometimes quite rough mechanical handling that it undergoes during projection.

There are two reasons for joining films together. Individual films may be joined together to make a longer film - this can save money when having film copied to video, for example. The film may require editing - cutting spoiled scenes out, rearranging scenes to give a more pleasing effect etc. Again, by removing unwanted material before having a film copied to video, a cost saving may be achieved.

The choice of splicing method may be dictated by the type of film used. Single-8 film and some Super-8 films have a polyester base which is not affected by film cement. Therefore these films must be spliced using tape.

Many people are very happy with tape splices; others have never accepted them. The theory is that because the tape forms a very thin layer over the film, the image is moved very slightly out of the focal plane when projected, resulting in a brief loss of definition on the screen. There is also a cost to adhesive splices, which are much more expensive than cement splices.

Cement Splicers

Cement splicers, when new, ranged in price from a few pounds to £60 plus. The cheaper splicers make a good, serviceable join but can be rather crudely engineered and may give a more visible splice. Better quality splicers give a more accurately cut film and cleaner scraping of the emulsion layer, resulting (with practice) in a splice which is almost unseen. The best splicers have a very small overlap which gives an excellent splice although it can be weaker because of the very small overlap.

See also Ensign Popular Cement Splicer instructioons

Tape Splicers

A tape splicer can be a simple device, sold at a low price, or a more complex automatic machine. Most tape splicers give similar results, depending on the care of the operator to avoid dust, hairs etc, and ensuring that the tape is free from air bubbles.

A problem with tape splices, on some projectors, is the "hinge effect" at the butt joint where the spliced film is more flexible. To overcome this, some tape slicers make a diagonal cut. However, this is more visible on the screen. Most tape splicers join the film at the frame line which should make the splice much less obvious, if it is done with care.

See also Quik Splice Tape Splicer instructions and Quik Splice Dual Gauge Interlock Butt Splicer instructions

When splicing sound films using tape, it is necessary to avoid covering the sound track. Special splicers or splices may have to be used.

Some time ago we had a request for the "recipe" for film cement. I very much doubt that the necessary ingrediants are readily available but for interest only, here it is, taken from. the 1975 Desk Edition of the Focal Encyclopedia of Photography, under the heading "Film Cements": My thanks to Roy Salmons (email: roysalmons@supanet.com) for this.


"There are various propietary film cements available. In all of them the action is the same; the cement softens the film base as soon as it is applied, and a few seconds later it is absorbed by the base. The two halves of the splice must be pressed together while the base is still in the soft condition. Properly made a splice should be stronger than the film.
The basis of most cements for nitrate film (now obsolete) is amyl acetate and for acetate film, acetic acid.
A suitable formula for both nitrate and acetate film is:
Acetone 8 parts
Ether 10 parts
Acetic Acid, glacial 1 part
To this is added about 1 part of 16mm film (with the emulsion removed) per 3 - 4 ounces (100 c.cm.) of solvent. More may be added to make a thicker cement."

 

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