REM-JET (or RemJet) is a removable jet black layer. The black coating, made of carbon particles, is located at the bottom of the film. It works as anti-halation and anti-static, it also offers lubrication and scratch protection.
Basically, every modern 35mm film has a similar structure to this one and it does not include the Rem-jet coating, the anti-halation coating is included in the film, and the need for an anti-static protection is not needed since photographic film cameras move relatively slow (max 3-4 fps during a few seconds):
- Film base
- Subbing layer
- Red light-sensitive layer
- Green light-sensitive layer
- Yellow filter
- Blue light-sensitive layer
- UV Filter
- Protective layer
- Visible light.
However, motion picture film moves through a camera at very high speed. The rem-jet acts as an anti-static during this motion. In some cases, film speeds are extremely fast and need extra protection. The structure is something like this:
Rem-jet has some very attractive properties. It is probably the most effective anti-halation backing yet made and it has some anti-static capability. It provides an improvement in both, quality and reliability over other anti-halation methods for color motion picture camera films. It is very easy to be removed in machine processing, which is how motion picture film is processed. However, its use in photography is quite different, especially relating to developing the film. It was meant to be processed by ECN-2. Without removal of rem-jet before processing will contaminate the color developer. That, will ruin the developer solution and the person developing it will be quite angry if he/she was not aware of it in advance.
Nowadays It’s possible to find stores that develop motion picture film, but sometimes at a higher price. A pre-soak in sodium carbonate is usually enough. You have to do it before you start the development and it only takes about 2 minutes. (*)
– Dissolve 100g sodium carbonate (calc.) in 1l water (35°C) (You can use it several times)
– Put the film in the tank
– Fill the liquid into the tank.
– Turn the tank once or twice.
– Empty the tank immediately.
– Fill water (35°C) in the tank. Shake the tank for 30 sec. permanently.
– Repeat once or twice.
The most common available motion picture film currently are:
- 5219/7219 VISION3 500T introduced in 2007. SO-219 is ESTAR-base variant.
- 5207/7207 VISION3 250D introduced in 2009.
- 5213/7213 (35, 16, & 8 mm) VISION3 200T introduced in 2010.
- 5203/7203 VISION3 50D introduced in 2011.
- Eterna Vivid 160T 8543/8643 introduced in 2007
- Eterna Vivid 250D 8546/8646 introduced in 2010
- Eterna 250D 8563/8663 introduced in 2006
- Eterna 250T 8553/8653 introduced in 2006
- Eterna 400T 8583/8683 introduced in March 2005, discontinued in July 2011
- Eterna 500T 8573/8673 introduced in 2004
- Eterna Vivid 500T 8547/8647 introduced in 2009
Companies like Cinestill sell this kind of motion picture film under their own brand, not only repacking and removing the rem-jet layer, but adding some chemical process, making it easier to develop in a normal store. For example:
The Cinestill 800T Tungsten is a re-treated
[repackaged] Kodak Vision3 500T.
The only problem of this is, that removing the Rem-jet layer, we also remove the anti-halation properties of the film. Example:
Light entering the film can reflect off the front or back surface of the film base and return into the imaging layers to expose them. When light spreads laterally beyond its intended boundary, an image appears to have a halo around it (halation).
The anti-halation layer prevents this by absorbing light that reaches it. The rem-jet carbon layer is conductive and prevents the build-up and discharge of static charges that can fog film. This is especially important in conditions of low relative humidity.
These two pictures are shot by myself with two different films, same conditions, same place and same light. The first one was shot in Polypan F50, a film without anti-halation layer. The second one, in T-MAX 400 has the anti-halation layer. You can see the halo and small “ghosts” next to the sources of light. That effect is the one that we will see using Cinestill films (or any film without that layer). Using motion picture film will not have this problem, but we will need to go through the hassle of removing the rem-jet ourselves or find a specialist for that.
Kodak T-MAX 400
(*) I recommend you to watch tutorials before removing the rem-jet by yourself, and always do a couple tryouts in not very important rolls. This information on removing remjet was extracted from here.