It is very important to remove the black Anti-Halation Backing of the movie film. Some people prefer to remove the backing before the film is processed, while others prefer to remove it later. There are pros and cons to each approach.
In many ways, it is best to remove the backing before the film is processed. If it is not removed before the processing, it is possible for bits of the backing to come loose during the development processing and become embedded in the emulsion. This can prevent that part of the film from being processed correctly, and will show up as spots on the film, after processing.
The problem with PRE-processing removal is that removing the backing before processing is more difficult than after processing. You need to be sure that the backing has been fully removed, but you can't look at the film before it has been processed. One way to deal with this is to take a small test strip of unexposed film, and see how long it takes to completely remove it WITH THE LIGHTS ON -- and how long it takes to dry COMPLETELY. Drying, of course, depends on how you process. If you use reels, it's probably impossible to get the film on the reel while it is wet.
So try both approaches (see below) and see which works best for you:
| Water | 700 ml |
| Borax Pentahydrate | 20 g |
| Sodium Sulfate | 100 g |
| Sodium Metaborate | 10 g |
| Water to make | 1000 ml |
For POST-development removal -- after the film is bleached and fixed -- place the film in the remover solution.
The time in the remover may vary from a couple of minutes to several, depending on the film, manfacturer,
temperature, water acidity, etc. -- but since you can work with the lights ON, it's opretty easy.
Remove the film from the solution and place it under a faucet of slowly running water. At the same time, gently rub the back of the film with a soft photographic sponge until all of the backing is removed. If it's difficult to remove, place it back in the remover for a few more minutes. Be careful not to scratch the film emulsion which is very soft at this point. Since the backing is dark, it's easy to see if any remains. When it's all removed, continue with the processing.
For more information, there was also a recent article about removing rem-jet backing: Robert Chapman, Photochemistry:Removing antihalation backings. PHOTO TECHNIQUES, 5-6/1996
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