120 Process Problem

[Jim Blob]

I've had the same problem with a bunch of films but i've mostly been using Kodak TMax100 or Ilford FP4 Plus125 so i'm sure that's not the problem. The fact that I haven't been using the center column that keeps the whole thing light tight sounds pretty promising! Cheers

[bowzart]

it's not the stirring rod, to be clear, that is needed. it's the center column. All paterson tanks, and their copies, have a center column. The reels slide onto this column. The whole shingdig then sits on a little spiked hub-thing on the bottom of the tank, then the funnel-top goes on top, then the lid, ultimately. It is that center column that makes it light tight.

This is a gripe I have. The Paterson tank is a superb piece of design; I believe it is in the MOMA design collection, for good reason. However, there is one thing wrong with it, which wouldn't be a problem for most of us, but for beginning students it is.

The lid is black. This suggests that if you are using inversion agitation you should be ok without the column. Students go in the dark, have trouble loading, put the film back in the tank, put the lid on and come out to get help. Film is fogged. The culprit here is the red plastic strip that goes around the top, that the lid fits on. It radiates red light in the tank. I am sure that for the little people who live in those tanks, the quality of light is lovely. But it ruins the film, and at their stage, students need success, not failure. Of course, doing that once usually takes care of it. To make the light trap work requires the center column and the funnel be assembled just as if the reels were in it. The only function of the lid is to keep the chemicals from falling out.

So one student got interested in this and called the distributor to ask about this, the answer came back "It has no function other than as a decorative accent".

Clearly, the committee which inducted the tank into the MOMA collection did not include a basic photo teacher in its membership.

They could have made that strip black and included a red stripe somewhere else on the tank. They could have made the lid a translucent red, so it would be obvious that light would be admitted.

[kevs]

I had that problem - my college had these new system 4 tanks - I found the lids leaked and the bayonetted funnel top came loose if inversion-agitated too roughly, leaving the film wrecked and me wearing the developer! Why they ditched the old design I'll never know - it's far more practical and easier to use. Also the lids are white or grey, so they're not light-tight.

One of my old S4 lids has a sticker with 'Selected for the Design Centre, London' on it.