Developing very large roll film for alt proc

A local group asked me to shoot 50 steam tractors and their owners yesterday with my pan cameras and I decided to try to do a 340 degree image with my longest lense on my 16" cirkut camera. I spooled up a couple of rolls at 18 feet, which would make a 360 image with my T-R 36" lense
I shot the photo hopefully without too many cirkut troubles, though I did find various new things to fix with the camera(sigh).I figured I would develop the photo by rolling it back and forth, like it was done in the old days in the field.
I tend to print the big photos with pop, van dyke, cyanotypes, etc and have been using rollo pyro with success.All my other negs have been done in large trays made for the negs, and I have trays to 10 feet. Since I have to roll the negs back and forth, and aren't going to make 18 foot trays, I feel that I need to find a developer that would be slower acting so the rolling won't affect it as much. Does anyone have experience diluting pyro for slower development. I could also go with PMK which is slower than rollo, but wouldn't mind going longer to keep development even as I roll the negative back and forth.
Any suggestions ?
Thanks, Jamie Young

I have no experience w that size negs, largest I do is 4x5, but I do use rodinal 1:100 regularly and get very even results. If you have experience w it, try it out w a spare neg. I really enjoyed your website when I looked at it a couple of weeks ago.

Jamie

You rock , I would like to see some of your work.
I do very large sections of fibre paper 30inch by up to 15 feet. I extend my development time and I center the image so that there is at least 2inch handling on either side when the print is rolled.
I use trays that look like under the bed storage, 10inch high x 20 inch wide x about 36inch long.
I really fill up the chemicals, over 30 litres per printing session for each chemical.
I roll the paper through the chemicals from the sides of the roll. I use panchromatic fibre paper so no safe light.
I have an application for processing very large sheets of FP4 so I would be very interested how this thread goes.
The application requires very precise development and agitation proceedures as the negatives are for alternative printing and I am perplexed on how to keep very repeatable Contrast and Density Range for this work.

Some people use rewind tanks for movie film. Try searching on Google for "hand processing movie (or 16mm super-8 etc.) film" and you should turn up a few sites that may provide some inspiration. If you don't have space to dry that long a sheet of film, you might also look for instructions to build a drum for drying long strips of film.

Another possibility might be to roll the film emulsion-side-out in a spiral on the outside of a long drum or pipe, taped at each end, and roll the drum in troughs (perhaps your 10 foot trays).

Thanks for the great ideas.
I have a bunch of rollo pyro around for my regular (shorter) negs, and might do some tests with greater dilutions to lengthen the developing time a bit.
I like idea of rolling around a tube, but when thinking about it I would need a pretty wide tube around 10 feet long and think it might be hard to wrap a 16" neg like that. I also just thought of using my 10 foot tray, having the neg run around two poles at either end which could turn easily)and attach back to itself , and just pull the neg around and around. Might keep development even enough.
Jamie

What about whipping-up one of those clear, plastic developing strips with the frilly edges like the old Kodak miniature developing tanks had with the cork center? You could use sheet acetate and something like one of those freaky hair irons that put the sawtooth pattern in horribly dyed hair to make the wavy edge...

Of course, you could take 18 feet of sewer pipe, a bunch of lawnmower wheels and a big hand crank and make the World's longest tube processor! Put a Tee in the center with a clean-out plug and put your chemistry overhead to gravity fill the tube; empty on the ends into buckets and wash same way from center out.

Of course, you would probably have to do it outside and at night...

I am reasonably confident that I remember government surplus rolling tanks (reel-to-reel-and-back-again) for processing very long rolls of wide film (from aerial cameras, obviously) but it might be hard to track one down today. Of course if you can, life will be much easier.

Cheers,

Roger (www.rogerandfrances.com)