Large format, Part III

Large format, Part III

It seems worth finishing off the excursion into 5”x4” photography with a little bit about developing the film, and what you can do after that…

The traditional way to develop sheet film, like glass plates, is in a dish, in the dark. I did this a few times when I was in my teens – somehow, I got hold of what must have been among the last plates Ilford made, and exposed them in a Patent Etui that I’d acquired.

However, it’s REALLY hard to work in complete darkness, which panchromatic films require (pan=all, chromatic=colours: unlike the earlier types of film, panchromatic emulsion is sensitive to all colours of light). A tank of some sort is better. There are some tanks available new, but they’re hard to find and expensive. I have two alternative solutions, neither of which is on the market new.



I have an American Doran tank, which I acquired from a friend. Unfortunately, as the lid is neither waterproof nor fixed, there’s no way to agitate the film, and reviews suggest that the uneven development you’d anticipate eventuates (there’s your word for the day!) There are one or two developers, though, that require no agitation – I may give it a try with one of these. It adjusts to a very wide range of film sizes, and holds up to 12 sheets at a time. In case you ever want to develop that many pictures at once!

Agitation: if you aren’t familiar with the idea, and didn’t read my blog a while back on darkroom work, you need to stir up the developer and fixer during processing, so that the emulsion is constantly in contact with fresh chemicals. Most commonly, this is done by inverting a sealed tank, but rotating the film-holders in a circular tank is also common.



And I have a Paterson Orbital Processor, devised in the late Seventies or early Eighties for developing a single sheet of 10”x8” colour paper. It came with little studs to subdivide it for up to four 5”x4” sheets, so it’s just right for sheet film. I modified my tank to allow solutions to reach the back of the film and remove the antihalation coating that many sorts of film have – I simply stuck on some self-adhesive plastic bobbles. The tank gently rotates and rocks on its base to agitate the solutions. It’s worth looking up on YouTube for the sheer looniness of the action.

The basic processor requires the user to keep sliding the tank around on a base: being lazy, I bought the powered agitating device. Either way, the tank gives continuous agitation, so developing times are shorter than with the periodic agitation of a conventional film tank.



Each individual type of film has a unique edge cut-out pattern, outside the picture area. This allows you to differentiate between kinds of film in the dark, though it’s best to use a system so that you only have one film type in use at a time.