A little bird that is definitely real and can obviously read minds told me that analog is king and people want to develop their own 35 mm film. That’s a noble cause and you even get a prize at the end. The prize is not Nobel. For 35mm home development you need stuff, the stuff you need depends on how you decide to go about it. This list will not include all the outliers, it’s going to be too long anyway. Let’s assume you have your camera, your exposed film, and your chemistry.
Option One
- Changing bag
- Daylight developing tank
Option Two
- Auto-loading daylight developing tank
Option One comes with a whole suite of other choices. Metal or plastic tanks & reels being the main one. Metal tanks and reels have some solid things in their favor. They use less chemistry, in the same line, they’re smaller. For agitation, you gotta shake. They can also be kind of a pain ‘cause you need specific reels for each film format, and loading those reels is a bit of a learning curve. Oh, and they’ll last forever and can be cleaned in a dishwasher and dried in an oven. If you go plastic you get to choose what brand is the prettiest. Holy crap there’s a lot of brands. Some you can shake some you can’t and you have to use an agitator rod. Some can be sealed up and sat on a motor driven rolling base instead, which you can do with a metal tank if you try hard enough but that’s just asking for leaks. Plastic tanks pretty much all use more chemistry, but the reels generally adjust to whatever size film you shoot. It’s nice having a reel that’ll take 110, 127, 35, or 120. Versatility like that means they’re pretty big, so I hope you got a darkroom or a big ass changing bag.
Option Two has choices too. Well, a choice, have you got $200 or have you got $30? That can also be written as do you want to buy an Ars-Imago LAB-BOX, or search the second hand market for a vintage Jobo Auto-Mat 35. I know what you’re thinking, we all do, especially the birds. “Jobo isn’t that expensive as hell?” Not the one we’re after.

The problem with the above is, how do you use it? Maybe you luck out and get a crumbling pamphlet when you buy yours, good luck with that. I’m told there’s some guy out there selling a poorly scanned pdf for about what you’ll pay for the tank. Maybe I’ll buy that pdf if I ever need to know the difference between the white and black sprocket. So, here we go, instructions on how to use a vintage Jobo Auto-Mat 35. First, let’s make sure you got all the parts.



This tank doesn’t require a changing bag because the exposed film cartridge is loaded, everything is put together, and then it’s developed. There’s other vintage tanks that do the same thing, a bunch of Soviet brands, Kodak, Jobo, Yankee, and others are all out there. They all work basically the same, with the main difference being that for some the film cartridge comes out before the chemistry goes in and with others the film cartridge comes out at the end along with the processed film. The Jobo Auto-Mat 35 is one that soaks the film cartridge in chemistry. That pretty much means you’re going to either use all-plastic reloadable cartridges if you bulk load, or disposable cartridges. Just something to keep in mind.
Step One: one is cutting your film leader. Trim the leader to a right angle, then clip the corners. You can actually cut them a little deeper than picture, in fact it works a bit easier if you do.

Step Two: fold the trimmed leader back about a quarter inch. Fold it away from the cartridge so that the unexposed edge is touching itself.

Step Three: take the metal film clip off the bottom reel, it should be easy to remove. Slip the film into the film clip with them both curling in the same way, so that if you traced them they’d form an arc, not a wave. Tuck the folded over edge of the film into the folded over tab of the film clip. The photo at the left shows the orientation of cartridge and clip and the photo at the right shows how the film locks into the clip.


Step Four: slide the film cartridge into the cartridge sleeve. The protruding side of the cartridge spool should be on the open side of the cartridge sleeve.


Step Five: drop the loaded cartridge sleeve into the bottom film reel. The sprocket should be installed and you should take care to line everything up. Note that at this point you don’t want the film to be sticking out of the cartridge or cartridge sleeve really at all, it’ll just make lining things up harder later on.



Step Six: with the reel top and cutting tube threaded together, align the dots on the bottom and top reels. There are cut outs that fit together in both, drop the film clip onto the post on the slider on the bottom reel when you do. Note, the cutting sleeve must be threaded to the top reel, it only isn’t in the first photo so I could get a better shot.


Step Seven: this can really be part of the prior step, in fact it works better if you do it all at once but it’s twitchy as all-get-out. In the top film reel there’s a bump the recessed top of he sprocket fits into. In order to fit the sprocket to it, you need to slide the metal tab on the bottom reel that holds the sprocket it place to the side so you can pull it out just a hair. The hard part is getting the sprockets to align with the film sprocket holes. There’s recesses in the reels that help with it but the first time you try you’ll probably mangle the film a little, it’s fine, they’ll fall into place after a little wiggle.
Step Eight: drop the assembled reel into the tank bottom. Give it a slight twist until you feel it locked in.

Step Nine: place the tank lid on. The arrow on the lid will line up with the chemistry pour spout, then give the lid a twist to lock it on.


Step Ten: turn the handle on the film cutting tube counter-clockwise to wind the film onto the reel. As the film winds on you’ll hear a double-click on each full revolution. A 36 exposure roll will be fully wound after 14 double-clicks. A 24 exposure roll will be fully wound after 12 double-clicks. A 12 exposure roll will be fully wound after 6 double-clicks.
Step Eleven: grab the bit of the top reel that sticks out of the lid with one hand and turn the cutting tube clockwise. It’ll screw down into the tank. You will very likely not feel it hit or cut through the film and that’s fine. Just screw it down all the way, you atrocious screw-up.

Now, pour in your chemistry and process your film.