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colour photography (C41) home processing

Posted: Thu Jun 11, 2009 1:54 pm Etc/GMT-1+01:00
by numnutz
Hi - Sometime this summer, If it happens this year, I wish to try some large format (4 x 5 maybe 8 x 10) colour photography.

I have decided to try some Portra 400NC and process myself at home using a COLORTEC C41 Negative Kit 1 litre kit.

The processor I use at the moment is a Paterson motorized Orbital processor. I am happy with the monochrome results from this setup using Pyro developer, but I wonder if it is suitable for colour. This is because of the low amount of solution used, 200ml, with continuous agitation. Has anyone here tried this combination?

Has anyone got any other recommendations. I have experience of running a commercial C41 dip dunk processor but none using one shot chemistry. I wish to do this at home rather than bother with Lab processing.

Thanks for any advice you can give.


nn :D

Posted: Thu Jun 11, 2009 8:56 pm Etc/GMT-1+01:00
by Dave Tolcher
Hi, I havent got any tips for colour I am afraid :cry: but would be interested in your workflow for pyro with the Orbital. I am waiting for some whole plate film in the ilford run and will use pyro to develop in a motorized orbital. I was worried about the low solution volume and temperature control, also sticking negatives !

Many thanks

Posted: Fri Jun 12, 2009 12:43 am Etc/GMT-1+01:00
by numnutz
Hi - My Paterson Orbital was modified to prevent negatives sticking by putting small (pin head size) blobs of Fish Tank sealant in a cross pattern for each 5 x 4 with 2 blobs along each edge. This seems to work fine. The bigger the blob the more solution needed.

With a few negatives I noticed some uneven development in the skys - I put this down to uneven agitation around the fins so I carefully removed them. The only problem with doing that is you have to be careful when emptying the processor as the film may escape from the little red pegs if you tip over too far.

I use 150ml for each solution except for the fix where I use 200ml As you are using a larger format you may wish to increase this.

My one main problem is ensuring temperature control. I usually get the temperature of the solutions to a couple of degrees above 70 Degrees, warm the tank slightly above ambient room temperature and develop to the mean temperature about 7½ to 8½ minutes according to the scene photographed. I am going to experiment with a device sold to keep wine at a constant temperature (around 100 degrees F) for the colour process although for monochrome I will keep my present work flow as it seems to be reasonable consistent (judged by eye).

I am using HP5+, Foma 100, and Rollie InfraRed developed in Retro Pyro. acetic acid stop and a rapid fixer. When fixed I rinse with about a litre of water then pour back the used pyro developer for another two minutes with motored agitation. All solutions are mixed with distilled water. The final wash with tap water "the Ilford way" warmish in winter.

Hope this helps

nn 8)

Posted: Fri Jun 12, 2009 6:03 am Etc/GMT-1+01:00
by Dave Tolcher
Thats brilliant, thanks