Uneven development

[Jorge]

I drop the neg flat onto the surface of the 8x10 tray of developer and push it down with my fingers and follow with the second neg in the same manner. I rock the tray for 15 seconds, shuffle the negs, repeat, for 10 min.


I think I might see the problem. Can you see a noticeable straight line in the negative that has the dark area?

If so this is caused by negatives sticking together and the bottom one receiving less development in some parts.
Sometimes when you are rocking the tray the negatives do not stack on on top of the other one perfectly, the part of the bottom negative that is covered by the top one exhaust the developer and has no replenishmet. The part that is not covered by the top negative is receiving constant replenishment and receives more development. So when you see the negative one part is underdeveloped and the other is correctly developed, and there is a very noticeable straight line, or corner.

The dark streaks as you correctly deduced is from uneven development. I would say it has to do with the way you are rocking the tray and shuffling the sheets. Try this, introduce your negs as you are doing. shuffle for 30 seconds, stack the negatives in the tray and leave it. dont rock it. After 30 seconds shuffle again, etc...etc..this my work better.

 

[Jorge]

Can you scan it and post it. think the film is sticking together but I am not sure without seeing the problem.

 

[Jorge]

BTW how did you fix them? the same way? this might be also the problem.

 

[Jorge]

View Camera magazine has a one page description of a foolproof tray processing method for sheet film. Call us and we will send a copy

View Camera Magazine
505-899-8054 m-f 8-5 Mountain Time

Hey here is another idea, just call them and tell them Simmons posted this on the APUG forum and you want the article. Heck all it will cost you is a phone call!

 

[steve]

You know, I've been processing sheet film since 1967, and for the life of me I've never been able to process more than one sheet at a time in a tray because I get uneven development due to bad agitation.

Personally, I only do 1 sheet at time. While this is more time consuming, it is a lot less so than ruining a really good shot and then having to attempt to duplicate it - and some photos, as you know, cannot be duplicated.

My suggestion is not to try and hurry the process unless you feel comfortable using the technique described in View Camera Magazine. Also, I've found that one of the problems with large format tray processing can be not varying the agitation pattern.

My personal method is to rock the tray first front to back; then corner to corner; then side to side; then opposite corner to corner from the previous - then start the pattern over again. I have also found that agitation must be vigorous in order to wash the used developer off the face of the film and replenish the emulsion with developer.

Too gentle agitation and again, you get uneven processing. I have even experimented with putting the film in film hangars and laying two film hangars at a time into the bottom of a larger tray. I found that I had agitation marks associated with edges of the fim hangars. Back to one sheet at a time...

Finally, after years (20) of doing one sheet at a time, I bought a roller base and a daylight loading tank and process my sheet film in a tank. I'm a lot happier, and the film can be processed with the lights turned on so I can do other things while the film is developing and fixing.

 

[David Vickery]

The uncoated lens will not produce any streaks or noticable patterns of any kind. It will only produce an overall loss of contrast or wash of non-image light. Unless a bright light is in or near the field of the lens and then you will have the familiar "aperture" pattern.
I think that Jorge is right on the money when using the D-76. But with ABC you probably want a nearly continuous agitation and I use more volumn with ABC than I did with other developers. When I rock the tray with more than one sheet I stick my gloved fingers next to the film to hold it in place, but I don't keep them in the same place all the time. I am moving away from trying to process more than one sheet at a time and am experimenting with using a brush for agitation and find that I seem to have less density increase around the edges with this method. I am going to post a related question about this subject because uneven development seems to be a big hurdle to get over when processing the bigger sheet film. I had lots of problems with it when using PMK pyro but far less with ABC.