How to make redscale film

Redscale is a colour film technique whereby you reverse the direction of the emulsion in a film. Due to the way colour film works, you end up with high contrast photos that are very red, yellow, black tinged.

Below is a description of making a redscale film. It actually looks more complicated than it really is. I recommend reading through the instructions once before you first do it.

You'll need two 35mm colour films to do this (when you do it the very first time). I recommend finding some expired film somewhere for trying this out.

1. Let us start by naming one of our happy films 'A'. This is the film which will become the redscale film at the end.
2. Completely unspool film A. Just pull it all out.
3. Cut film A, leaving a small tab of tab of film sticking out of the canister. (Get an adult to help you with scissors if you have eye stabbing problems.)
4. Now we introduce film B, who is A's evil twin. Cut the leader off film B as shown.
5. Arrange film A and B as shown next to each other. Note that their emulsion sides are facing different ways - film B has the emulsion facing up (i.e. the lighter coloured side of the film), film A has emulsion facing down.
6. Take a piece of sticky tape, of the size shown in picture, and press both ends of the films against it, so that they are aligned.
7. Carefully fold over the sticky tape, tightly.
8. Do this part in either in a darkroom or a dark bag: Wind film canister A so that it takes up all the film from canister B.
9. Your films should now look like this.
10. Cut the film to separate the canisters. Note that if you cut in the right place, you can end up with another canister as in step 3, ready for making another redscale film with! (i.e. don't cut too close to canister B, leave a tab of film sticking out)
11. Now film A will seem odd and wrong because the film curls the wrong way. But it's all good.
12. Fashion yourself a film leader by cutting as per the dotted line in this picture. (I've already done it in this picture.)
13. And there you have it, a redscale film ready to shoot. Please remember to overexpose your film by a stop. You need to do this because the light has further to go to reach the emulsion (because it's facing the wrong way now).

Source :http://soup.create52.com/technique/redscale/