rotary developing question (8x10) : LUSENET : Large format photography : One Thread

I am just starting on 8x10 film developing. I bought a beslser motorized base and several unicolor drums. Question one: How much developer in ounces do I put in the drums for 8x10? Question two: The drums leak rather badly. How can I correct that? Sincerely, Jerry Cunningham

-- octagon (, April 15, 2002


To fix the leak buy a Jobo 3005 Expert Drum and use the Unicolor drum for a planter. You will be able to process up to 5 sheets at a time with about a quart(32 oz.)of chemistry.

-- Jeffrey Scott (, April 15, 2002.

- Unfortunately - I'll have to agree with Jeffrie...The Unicolor Base is OK but the drum will give you great streaks or uneven density at least - I figure you don't want that.

Also, if you do use a Unicolor, Beseler or Chromega drum that only spins in one direction, flip the drum aound ever minute or so. This will prevent (or eliminate) sine-wave streaking of your film.

But do get that Jobo drum, OK!!!

-- Per Volquartz (, April 15, 2002.

Sorry about my confusing post.

First I spelled Jeffrey wrong. Sorry!!!

Second, I said a "Unicolor base" - I meant your Beseler Base (they are virtually identical)

Third, I said "Unicolor, Beseler or Chromega drum that only spins in one direction" - I meant the base ...

Now if I could only learn how to spell...

-- Per Volquartz (, April 15, 2002.

I don't go over four 8x10 sheets for straight developer, and two sheets for 1:1 diluted developer. This much developer is needed for consistent results.

-- William Marderness (, April 16, 2002.

To ANSWER your question, try about 3 oz. Maybe you just have worn out drums. I use Beseler drums and mine don't leak. If you'll set everything up level, you can avoid those streaks. You're on the right track. Give it a chance before you junk it.

-- Alec (, April 16, 2002.

I agree with Alec. I've been using a Unicolor print drum for 4x5 film dev. for many years. Never a problem or streak. Mostly Agfa 100 in HC110. An 8x10 drum capacity is about 15 oz. without leaking. More than that will dribble out during rotations. And be sure it's all level. If yours leaks you need a new gasket that fits into the cap. BTW a Unicolor base rotates in both directions. Figure the amount of dev. for the number of square inches of film. Don't try to skimp. 8x10 = 80 sq. in. of film. Be sure the amount of dev. in the tank will process the amount of film.

-- Steve Feldman (, April 16, 2002.

I have a Unicolor roller and drum for processing 4x5 and 8x10 B&W film. I use about 250 ml of developing solution per sheet of 8x10 film and about 2/3 of that for two 4x5 sheets. I've routinely used 250 ml of developer for 120 film and 36 exposure 135 film; both of which have 80 square inches of film area. I see no reason to use less developer for the same square inch area in 8x10.

My drum takes a plastic gasket that seals the tank against leaking. When I first got the tank it leaked like a sieve inspite of the gasket. I friend gave me another gasket and that solved the leakage problem instantly.

To the eye these gaskets are identical and I see no reason for the first one to leak, yet there you have it. If you have more than one gasket and drum then switching gasket and drum may be all that it takes.

I get wonderfully even developing when I use the base and drum, especially in areas of the film where there's lots of even tones like the sky. Now my base is bi-directional and I'd have my doubts about getting even development from a unidirectional motor base like the old Cibachrome bases.

-- David Grandy (, April 16, 2002.

I use one of the bases that waves back and forth so I have not problems. My tank does not have a name on it but it works great for me. The inside is not flat like most are. It has little ridges so that the fixer can get to the back of the film and clear it. I use only 5 oz of developer and find it is enough.

I would get rid of the leaky drum. It might short out the motor in the base if it gets wet.

good luck, Jay..

-- Jay Lynch (, April 16, 2002.

I've pasted a piece of cardboard on the roller (on the drum should work well also). That provides the wave motion i.e., in addition to rotation, the drum also rocks on end. I've never actually experienced uneven development before i.e., without the cardboard but I figured that it should help with bromide drag issues anyway. Cheers, DJ

-- N Dhananjay (, April 16, 2002.

I use a Unicolor autoreversing base with Unicolor print drums for 4x5 sheet film. I've seen no streaking with a variety of films and developers. I use 250ml for up to 2 sheets and 500ml for up to 4.

As for leaks, I have 5 drums, and all but one of them leaked badly. But the repair is simple. Remove the thin, hard plastic gasket, then remove the thicker soft seal, which sits underneath it. Run a gernerous bead of 100% silicon rubber (available at any hardware store) in the channel where the thicker seal seats. Reseat the seal and wipe up any excess. Now put another bead on top of the seal and reseat the hard plastic gasket, sandwiching the second bead of silicon between the soft seal and the hard gasket. Again, wipe away any excess. Now fully reseat the lid onto the drum and leave it rest for 24 hours. Once the silicon rubber sets, your drum will be as sound as new.

-- Ted Kaufman (, April 17, 2002.

Although the unicolor drums work, I find that for me the JOBO 3005 is much better way to work. I hate to process film, and the JOBO 3005 has made it somewhat OK.

-- mateo (, April 17, 2002.

Moderation questions? read the FAQ