View Full Version : Uneven development in skies

Steve Hamley
4-Nov-2009, 11:38

I've been getting uneven development in skies (high negative density) when tray developing 8x10 negatives in 8x10 trays (there's adequate size for the neg to lay flat, plus a little). So I thought I'd probe the "collective" about potential troubleshooting methods.

I'm using pyrocat-HD in GLYCOL 2:2:100 for Tri-X, 500 ml of solution at about 70 degrees, 30 seconds initial agitation followed by 10 seconds each minute. 500 ml will give me a solution depth of 3/8". The non-high density areas look good.

Now my pyrocat solution A and B are about 2 years old, and as a consequence there's a relatively large amount of air "headspace" in the bottle.

The usual suspects are old developer and not enough solution in the tray, so to troubleshoot, I'll try fresh developer, more developer, and maybe a different developer since I have some fresh PMK I was playing around with.

Any other ideas?

Thanks! Steve

Robert Hughes
4-Nov-2009, 12:58
I've gotten uneven development in skies before, due to insufficient agitation. Nowadays I stroke my (gloved) fingers lightly across the negative during development to ensure more even development of large areas.

Jon Shiu
4-Nov-2009, 13:04
Hi, you might want to try brush development.


4-Nov-2009, 15:12
Bigger trays might help.

Frank Bagbey
4-Nov-2009, 19:47
Are you sure that is the problem? If you use glass neg carriers, you could be getting a reflection of sorts that only occurs at certain magnifications that looks alot like the problem you are describing.

Tony Karnezis
4-Nov-2009, 20:27
Steve, I had the same problem until recently when Michael Smith corrected the problem in my work flow.

How do you transfer the negs from the presoak to the developer? One by one or all together? In my effort to prevent scratches on Efke PL100, I would transfer the batch of negs together in a stack from presoak into the developer. Now that I carefully transfer them one by one, I stopped having the problem.

If that's not the problem, what about your development method? I tray develop 8-8x10 negs at a time and shuffle them constantly, roughly every few seconds. I'm not sure how to calculate how much agitation each one gets since the agitation occurs when I pull the neg out from the bottom of the stack. You say you agitate each neg 10sec/min? Could you explain what you mean and how you agitate?

Jan Pedersen
4-Nov-2009, 21:16
I believe it is the (B) Potassium Carbonate that is to old. Your A part is fine in Glycol but i have had the B part go bad after a little over a year.
Try with a new mix of Potassium Carbonate.

Tony Karnezis
4-Nov-2009, 22:08
Jan, I didn't think Steve's developer was too old based on Sandy King's experience.

Stock B, a 75% sodium carbonate solution, is always mixed in water, even in the glycol kit where Solution A is mixed in glycol. My experience is that Stock B mixed in water has a shelf life of at least two or three years, which is why I suggested that it has an indefinite shelf life. I think that if it goes bad in a year or less it must have been contaminated.

Sandy King

Steve, is it possible you could have contaminated solution B?

5-Nov-2009, 07:14
I believe the uneven development is due to insufficient agitation, not old or contaminated solutions. The problem as described is not lack of development, but uneven development.

Agitation for ten seconds every minute is not enough with sheet film using the 2:2:100 dilution. This is a very energetic dilution and leaving the film in the solution without movement is almost sure to cause uneven development. I would suggest that you try a more dilute solution, say 1:1:100 and agitate the film vigorously for one minute at the beginning, and then for five seconds every thirty seconds.

In my own experience neither the A stock mixed in glycol or the 75% potassium carbonate B stock should have gone bad after two years. I have on hand solutions of three or four years old that are still working fine. And in any event your problem appears to be one caused by insufficient agitation, not old or contaminated chemicals.

Sandy King

5-Nov-2009, 08:09
bigger trays i reckon. on the neg, are the edges darker from the wave effect of the edges of the tray? cheers, john

Steve Hamley
5-Nov-2009, 08:31
Thanks everyone! Looks like more agitation possibly with a brush might be a good place to start. And yes it is uneven development in mostly even toned skies, not underdevelopment.

I've attached a crop of a jpeg. The sky is clear blue, cloudless, with a very little haze near the horizon. Please note that the "spots" in the left hand sky are a result of the scanner platen and are NOT present on the negative.

Frank, the artifacts are visible in the negative.

Tony one-by-one from presoak to developer. Agitation is by fore-aft, side-to-side, and a "circular" or "rotational" rocking of the tray - I usually do some of all three every agitation cycle.

Sandy thanks for the info. My contrast is about right so I'll have to play with agitation methods.

And thanks everyone - this is just the kind of information needed to help solve problems.

Cheers, Steve

David Schaller
5-Nov-2009, 08:54
I essentially follow Sandy King's advice above. I do two 8x10 negatives at a time in 1:1:100 solution at 70 degrees, starting with one liter of water. I agitate constantly for the first minute, then every 30 seconds rotate the negatives. The trays are just a bit bigger than 8x10, so I don't think you need bigger trays.

Steve Hamley
6-Nov-2009, 16:36
Thanks Dave,

I was trying to get away from the long development time by using 2:2:100, but maybe that was a bad criterion.

Anybody have comments on using the 2:2:100 dilution with success in trays?

Cheers, Steve

6-Nov-2009, 20:30
Thanks Dave,

I was trying to get away from the long development time by using 2:2:100, but maybe that was a bad criterion.

Anybody have comments on using the 2:2:100 dilution with success in trays?

Cheers, Steve


Just agitate more frequently, and make sure that you give a very vigorous agitation when you begin development.


6-Nov-2009, 21:17
I found that sorting through the stack with the emulsion up gave uneven skies in my tray processing (pre-jobo). The developer is sloshing over the edges when you push down giving more development to the edges where the agitation is more vigorous.

When I turned the sheets over and developed with the emulsion down, then pulling the bottom sheet out gave a sudden exposure of the sheet to new developer all at once. At the time I was having this problem a few years ago, I tried many approaches. The emulsion down approach, with flat bottom trays (to avoid scratching) was my solution.

ronald moravec
10-Nov-2009, 14:23
Uneven developmet is almost always from two causes.

slow uneven immersion. The wet dry edge must start and proceed across the film rapidly and without stopping or backtracking.

insufficient agitation upon immersion.

I never presoak. This is only to make hand stack agitated film not stick. There is no other reason to presoak.

All the above true for 35 120 4x5

bob carnie
10-Nov-2009, 15:21
I have found that the first 15 seconds of development are critical and agitation is needed to move the developer onto all areas of the film.
We use Jobo for the last 15 years and to this day still manually agitate to make sure developer is reaching all areas of the film for the first 15 seconds.

Your sample is classic {under agitation} during the initial stages of the development process.

10-Nov-2009, 18:16
I agree that it is uneven development. Now I have also had that problem in the past, but after having lost nice images to uneven dev., I now tend to over agitate (within reason!) if my subjects have large areas of sky, or a similar even toned subject, and I haven't had any trouble with uneven dev since.