Uneven Development

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I have recently made the jump from shooting 4x5 (TMax100 with D76) to 11x14 (Bergger BPF200 with PMK) with a whole lotta learning curve and fun with some frustration in the process!!

In some of my prints (AZO+ Amidol), I have noticed a (negative) density increase along the edges - very difficult to even notice on the negative but very ugly on the print. I develop one sheet at a time in trays, the trays are about 14"x18".

I assume that this density is from uneven development due to the more vigerous movement of the developer over the edges of the film. Before I go out and buy a 18x22 tray (I never had the problem with 4x5 in 5x7 trays), I would appreciate validation (or not), of my theory and/or any other solutions/suggestions because this simply cannot continue!

Thanks for all the help!!

-- Matthew Hoag (hoagm@bostonpizza.com), May 24, 2002


It's actually a lack of sufficient agitation in the center compared to the edge. The difference being that you need more vigorous agitation to get even development. For large film, I find it better to develop two sheets at a time, agaitating by bringing the bottom sheet out and up to the top every fifteen seconds. This always seems to give smoother results than single sheet development.

-- Carl Weese (cweese@earthlink.net), May 24, 2002.

Think pyrocatHD @1:2:100. Much more forgiving than PMK in a tray.


-- Clay Harmon (wcharmon@wt.net), May 24, 2002.

What is your agitation cycle, and how vigorous is your agitation?

-- John McDonald (jmcd@napanet.net), May 24, 2002.

Sounds like it is not uneven development, but bellows flare.

-- Michael A. Smith (michaelandpaula@michaelandpaula.com), May 24, 2002.

I think Michael is correct. If it was uneven development it would look, well, uneven. Bellows flare on the other hand will manifest itself a a gradual increase in density, with no uneven streaks or mottling.

-- Per Volquartz (volquartz@volquartz.com), May 24, 2002.

My agitation is continuous for the first 30 seconds then I lift one side of the tray about 1 inch every 15 seconds (changing sides I lift each time).

Bellows Flare!? Can anything be done about that (light reflecting off the bellows onto the film I assume)? The camera I use is a B&J folding wood field (I don't know the model or year it was made) It does have a tapered bellows all the way along.

Thanks, Matthew

-- Matthew Hoag (hoagm@bostonpizza.com), May 24, 2002.

The are three causes of bellows flare. You can solve two of them as follows:

1. Use a compendium lens shade. Extend it to the max without getting cut-off corners. (After setting your shade keep the shutter open, but stop down to the f-stop you intend to use. FROM THE FRONT of the camera look through the compendium and through the lens to make sure you can see each corner of the ground glass completely. If you can you will be fine.) By eliminating excess light from bouncing around inside the camera you will reduce bellows flare.

2. When making your contact print gently burn in edges to eliminate light "leaking" off the print. (In other words correct for density differences while printing.)

The third problem - camera design (too small bellows - too close to the film size) can only be corrected by shooting 5X7 film on an 8X10 camera or 4X5 on a 5X7. Some cameras have bellows that are too "tight" around the image format. This is usually caused by camera designers trying to create as small a package as possible...

-- Per Volquartz (volquartz@volquartz.com), May 24, 2002.

Per has it right, but in my experience it is only the camera that is the problem. I good lens shade is a must, but the only truly satisfactory solution is to use a camera one size larger than you needed for the film size.

Another problem could be that you are developing one sheet of film at a time. When I started using 18x22 (at $45/sheet) I wanted to be super careful and developed film one sheet at a time--unlike my normal 8-12 sheets at a time. They all were uneven. So I went to developing six at a time and they were perfectly smooth. I'd recommend that you develop six at a time.

-- Michael A. Smith (michaelandpaula@michaelandpaula.com), May 24, 2002.

Thanks to all for your excellent input.

I do use a compendium shade and it seems to me that as the camera design is square I should not be getting the same amount of density increase on all 4 sides of the film. The back is 16x16 and therefore shouldn't it follow that if the long sides of the film are 2+ inches further away from the bellows that there wouldn't be the same amount of light bouncing onto the film? Seems logical to me but... (any thoughts?). Anyway I will try developing a couple of sheets at a time and see if that makes any difference.

Thanks again.


-- Matthew Hoag (hoagm@bostonpizza.com), May 26, 2002.

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