You will need:
- Your Holga120 (mines the GCFN)
- A used 120 spool (I don't know why I put two in the photo)
- Electrical tape (gaffer tape will also work, but it leaves sticky gunk)
- Bits of foam
- Rubber bands (the thick ones work well)
- A roll of film (I know this one is already developed, it was completely over-exposed so I put it in a canister for tests like this)
Step One: Open the back of your holga. You will need either the 6x6 or 6x4.5 mask if you want to get the images printed normally.
Step Two: Get the spool and wrap the rubber bands around either end to leave a gap that is big enough the let the film through.
Step Three: Attach the film leader to the spool with tape.
Step Four: To make the 135 mask, get some black card stock (this is 160g) and cut out a square that's about 63mm square, then in the middle cut out a gap that is exactly 36mm wide and either 24mm or 36mm high (depending whether you want the sprockettes exposed).
Step Five: Place the spool in the right hand side, like loading the 120 film.
Step Six: Place the canister in the left had side and support the top and bottom with the foam. Layers of thick card might work, too.
Step Seven: Because 135 has no backing, you will need to block off the window with the electrical tape. I have only done one layer hear, but feel free to do more.
Also block it off on the inside for maximum light-proofing.
Step Eight: Close it all up and wind the film on a turn and a half and your all set. For even more security, you may wish to seal all round the edges with tape.
When you have taken a shot, wind the film on 21 clicks, if you want to try with wider shots, calculate yourself how many clicks you'll need. It helps to use a piece of paper or something.
What do the results look like? Take a look for your self.