This article is about loading 120 film. Instructions for loading 135 film are also available.

Word of caution

Loading the 120 film roll onto the Jobo 2502 reel (for use in the 2520 tank) is, subjectively, a more difficult task than loading a 135 film. That's because the film is wider, making it more likely to bend. Some care has to also be taken in order to load two rolls in a way they won't overlap with each other.

For those reasons I highly recommend first a dry-run practice with lights on. It's worth destroying one roll of film this way in order to maximize chances of a successful development later (of rolls with important photographs on them).

The 2502 reel

The Jobo 2502 reel can develop one roll of 135 or two rolls of 120 film. The latter is wider, and the reel has to be set up to fit it.

To adjust the reel, unscren both sides and reassemble at the wider setting.

Two Jobo tank reels, the top one narrower, and the bottom one wider.
Two 2502 reels. The top one is set to accept film in the 135 format, and the bottom one in 120 format.

Two rolls vs one roll

Because 120 film is shorter than 135, it is possible to load two rolls onto one reel. However, this could potentially pose a problem: the second roll could be loaded too far, overlapping with the first roll. To prevent that, the 2502 reel has a little red safety tab that will prevent a roll from getting loaded past it. The process is:

  1. Unlock the red tab to allow the roll to get loaded past it.
  2. Load the first roll. Make sure the end of the first roll is past the red tab.
  3. Lock the red tab.
  4. Load the second roll.

It might be a little bit tricky in the dark. More on that below.

The Jobo reel with a red tab on the side.
A red tab in the unlocked position. When pushed in, it would prevent the roll of film to be loaded past it.

Loading the film

Before turning the lights off, make sure the following is laid out on your work space (or in the changing bag) in a way you'll be able to find it in the dark:

Then, follow these steps:

1. Lights out

Before unrolling the film, remember to turns off the lights. Work in darkness untill the tank lid is closed.

2. Setup red tab

To develop two rolls of film, unlock the red tab - pull it out. To develop only one roll do the reverse - lock it, push it in.

3. Unroll the first film

Unroll the first roll of film. Discard the paper. At the end, the film will be attached to the reel using a tape. Remove it carefully, but don't just put it aside. Best to tape it back to the paper (and not the film!), to the wall, or elsewhere. The important thing is to make sure it doesn't get stuck to the film itself. This could lead to an undeveloped rectangle on one of the photographs.

4. Cut small corners from the begging of the roll

Use scissors to cut small triangles from both sides of the very start of the film. The triangle side should be around 3 mm long. This will help loading the film.

5. Load the first roll

There are plenty of tutorials and YouTube vidoes online how to do this, go check them out. However, there are some tips I have that I haven't seen online before.

Firstly, when "walking" the film onto the reel (by rotating it back and forth), push the sides of the reel towards each other. In other words - keep squeezing it. This will increase the friction between the reel rails and the film, and help to push it all the way in. This is especially usefull when developing two rolls, as it gets harder to walk the film all the way to the centre by simply gently pressing your fingers while rotating the reel.

The other tip is to make sure the first roll is loaded past the red tab. It might not be obvious in the dark. One way is to find the red tab on the outer side of the reel, and - in the same place but on the inner side - count the number of empty rails. There should be three.

The Jobo reel with film loaded and a red tab underneath.
Once the first roll is loaded, make sure that there are 3 free rows of rails in the same spot where the red tab is

6. Lock the red tab

With the first roll loaded, it's time to lock the red tab. This will prevent the second roll from overlapping with the first.

7. Load the second roll

The process is the same: cut the corners, load.

8. Wrap up

Put the reel onto the center core and place them in the tank. Close the lid. Make sure it's tight. Double check everything - that there's no film laying around and everthing is ready. Then it should be safe to turn on the lights.

Other resources