Processing 8X10 film

[David Grandy]

I've been processing 4X5 black and white film - mainly Agfa APX100 - in a Unicol or drum. I use the Unicolor motor base as well. I've had very good results usi ng D-76, D-76 1:1 and most recently Rodinal 1:25. The volume of developer I've u sed is about 100 ml (three ounces or so)and as I say, I've gotten good results.

I recently bought a used B&J 8X10 and to this point have only exposed and proces sed two sheets of film. One sheet was just underexposed and the other seems to h ave markings in the area of the sky. I doubt if I could see this in an area of the print which had more going on than a general gray but it's very noticeable i n large areas of even tone.

I used the same 100 ml of developer for the 8X10. Do you think that I've used t o little volume of dveloper? I should say that I always do a water bath before t he dveloper stage. Would that have anything to do with this problem? If anyone is using the Unicolor tank and 8X10 I would appreciate any guidance in this are a.

[Chad Jarvis]

My guess would be that you are exhausting your developer. I develop exclusively in D-76 1:1, though in open trays, but hear my logic. Kodak rates a gallon of D-76 1:1 for 10 sheets of 8x10 film if you extend development times by 15% after each 4 sheets processed. With 3785ml per gallon, I'd say your pushing that 100ml of developer a little too far... even if you're developing in a drum. I've never been able to get consistent results developing more than 6 per a two liter batch. I would try doubling or tripling the amount used.

[William Marderness]

The Film Developing Cookbook recommends no more than 4 8x10 sheets be developed in a liter of straight D-76 (or similar developer). This means you need 250ml of D-76 straight developer per sheet of film, regardless of the dilution. For one liter of D-76 1:1, 2 sheets may be processed. At 1:3, you would need 1 liter per sheet.

Many think this is over-kill, but I follow it, as it helps ensure consistency when developing negatives of various densities.

[John Hicks]

I use the Unicolor drums for both 8x10 and 4x5 without problems; I use at least 250ml solution, no water bath.

I think you're just not using enough solutions.

BTW, a Unicolor 11x14 drum will hold two sheets of 8x10. The 16x20 drum will h old four sheets but I've never had nerve enough to try it with film. <g>

[Ron_673]

David.... I use a Beseler 8X10 drum and Rodinal 1:25 to process single sheets of HP5+. I have had very good results using 120 ml of developer. I also use a water bath for 30 seconds before the developer. I hand roll the drum. I have never tried the motor base.

[Erik Ryberg]

Agfa says you need 10 ml of Rodinal per 8x10 sheets. At 1:25 that's 250 mil. Agfa's probably being conservative but that's what I use and I've never had any problems. The stuff is cheap anyway. An 11x14 drum will hold 500 mil and an 8x10 will hold 250 but you run into trouble with higher dilutions. I can do two sheets at 1:50 in an 11x14 drum but I can only do 1 at 1:100 or the developer spills out the top.

[james mickelson]

I use 250 mls for 4 4x5 sheets of Tmax in an 8x10 Uni drum. Works great. I would use more than less and I use it one shot. James

[Chris Partti]

I've had no problems with 150ml of HC110 solution B in 8x10 Illford drums.

[Sal Santamaura]

David, your experience with "markings in the area of the sky," i.e. uneven developing, parallels mine when attempting 8x10 in a Unicolor Drum on a Unicolor motor base. These results occur regardless of developer quantity, and, I believe, are an unavoidable result of turbulence around protrusions used to restrain the film as well as near the edges of the drum. I've given up on the Unicolor approach for this reason.