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yeknom02
6-Jul-2012, 12:52
Guys,

I have been processing my sheet film in a Beseler print drum for a while now. While I enjoy being able to just set everything up and flick a switch, I also want to learn how to process in trays, for a variety of reasons. It's more "old school," for one, but it might be a nice trick to have up my sleeve if I've shot 6 or more shots in a day. That would cut my processing times down to a third of what it would be in the Beseler. But before I start, I naturally have a couple questions.


I have 8x10 trays that I use for my paper processing. I'm guessing these would be sufficient for film processing? (I shoot 4x5) Other than using a tempered water bath (which I unfortunately can't set up due to space) do you have any recommendations for adjusting my paper processing setup for film?
I'm worried about fingers in the developer - that if I keep at it for years, I could develop issues with my skin (dermatitis or something). I use Playtex rubber gloves for my paper work, but would these scratch the emulsion if I wore them during film processing? Anyone know where I can get extra-large latex gloves?
I'm wondering if there are any tips you could share - methods of preventing scratches that you wished someone had told you before your first time tray processing. I just know that my next gallery-worthy shot is going to be ruined by a scratch...

Jeff Dexheimer
6-Jul-2012, 13:25
For trays I just went to menards and bought several small storage containers. They measure 5x8 and have a convenient snap on lid so I can store unused chemicals easily. Note: I only store fixer and stop bath. I never reuse my developer. They were cheap and their the perfect size for 4x5.

I submerge my fingers right in my developer, but when I precess IR film I use nitrile gloves. Never had a scratch.

Emulsion side down always. I had scratches galore when I processed with the emulsion side up.

cyrus
6-Jul-2012, 13:37
After trying tanks and sloshers, the best and cheapest solution I've come up with for tray developing 4x5 negs is to take a film hanger and bend the handle, so you can lay it flat on the tray bottom, covered with developer solution, and the handle sticking up. I posted a photo of this before:
76763
You can stack two or more of these on top of each other too, as long as your tray is deep enough. The handles can be used to introduce agitation.


Print trays are fine just make sure that there's nothing scratchy on the bottom like sharp pointy plastic burrs. People say emulsion should be down but then it inevitably rubs on the bottom of the tray, and even if that's totally smooth its better to not rub anything at all against the delicate soaked emulsion if you can avoid it, so I prefer emulsion up

My best tip: don't be greedy with the developer solution -- pour a decent depth of solution in the tray so the negs can float freely in there, thus minimizing scratches and also ensuring more even development. Don't crowd the negs. Don't agitate the tray as hard as you might with paper either since then the edge of one negative is bound to scratch the emulsion side of the negative below or above it.

There are lots of ways to scratch negs so there are lots of tips on how to not scratch them. Emulsion-side up probably helps, to minimize scratches from the tray bottom. But whether up or down, scratches caused by the corners/edges of other negs is the real issue, especially if you fan or shuffle the negs while they're in the developer as is widely encouraged, so don't start with a large stack of negs; start with a 2-3 negs at most until you get the hang.

Another problem to watch out for is negs sticking together. THis happens when a dry spot on one neg emulsion presses up to a wet spot on another negative. So I like to individually dunk and pre-rinse the negs in water so they're entirely slippery and wet when going into developer, thus are less likely to stick to each other. However, rember that you'll be dealing with these slippery negs in the dark so they may slip out of your hands too, which can be really inconvenient if you drop a neg without knowing as you move them from tray to tray. Keep count.

Long-term skin exposure to the developer can cause allergic responses as well as general skin drying -- I find that cheap plastic gloves made out of the sandwich bag material is sufficient and does not scratch so I'm pretty sure your gloves are fine too as long as they're the "dust free" variety. Most of the time you'll be handling the negs along the edges anyway.

jeroldharter
6-Jul-2012, 16:13
Use nitrile gloves which have a much better feel than playtex gloves.

Use a bowl of ice water for dipping your fingers so you don't heat up the negatives.

If you don't have a tempering bath, you can try the "pass through" method (or some name like that) in which you cool the developer below the desired temp anticipating that the ambient room temp will warm the solution above the desired temp - in other words the for a desired development temp of 70, start at 68 and finish at 72.

Be careful about dust. More dust lands in an open tray than inside a Beseler drum.

Maris Rusis
6-Jul-2012, 16:29
When doing a large number of 4x5 negatives in a tray don't be afraid to use temperatures well above 20 Celcius if you gain an advantage.

A few days ago ago I finished a darkroom session of 38 sheets of Fomapan 400 in the 4x5 format. I used a four place slosher travelling through a row of 8x10 trays. The slosher enables me to carry and transfer batches of film with minimal contact with processing solutions. To speed things up Xtol developer was heated to 35 Celcius (95 Farenheit) to give a time of 3minutes 25 seconds per batch of negatives. To keep temperature stability I used a small developing tray floating in a bigger tray of hot water. All the negatives are fine. If I had stuck to 20 Celcius my developing time would have been 10 minutes 20 seconds and I would not have finished the job until the next day. And I would have been bored out of my skull. Standing in the dark for two days rocking a tray is not a creative moment in photography.

Modern black and white films can take developer temperatures up to 100 Farenheit (sometimes beyond) without harm BUT:
Agitation must be smooth, quick, and continuous to avoid uneven development because of the short times.
Temperatures and times have to be accurate because the margin of error gets small.
All processing solutions should have similar temperatures to avoid thermal shock to the film and the possibility of reticulation.
Film emulsion softens so the only things allowed to touch it are liquids and air; no fingers, no other negatives, no squeegees, no chamois. Nett result: no scratches.

Leigh
6-Jul-2012, 16:51
I've used Diafine for tray development for many years, with excellent results. It has two distinct advantages:
1) It does not care about temperature. Anything from ~65°F to ~85°F is fine, which makes it great for summer-time use.
2) It does not care about time. Five minutes in each solution and you're done, regardless of film being processed.

Replenishment is accomplished by replacing the lost volume of Solution A in its bottle, then adding the same amount
of fresh Solution B to its bottle. Shelf life of both solutions is measured in years, even with use.

Stop bath, fix, and wash should be at the same temperature as the developer, whatever that may be.

I use the dimple-bottom Cescolite trays, unfortunately no longer in production. These minimize the surface area that
might contact the film, although there should be no contact anyway. Emulsion down, always, to minimize scratches.

- Leigh

Leigh
21-Jul-2012, 23:24
I use the dimple-bottom Cescolite trays, unfortunately no longer in production.
Sorry, that's wrong. They are still in production, and available from all the major online photo dealers.

Apologies for the mis-information.

- Leigh

Peter De Smidt
21-Jul-2012, 23:45
You can make some very low toxicity developers. Google Pat Gainer's PC-TEA, for example. With those there'd be no need to use gloves, but with other forumlas you should definitely use nitrile gloves.
Practice with some non-important film in the light. You can use previously developed film from pictures that you don't like. If you're like me, then you'll have a lot of them. 6 sheets is a good max at this point.
I always use an 8x10 tray for 4x5 sheets. Use plenty of developer, and dilute it (or adjust the temp) so that your development time is about 9 to 10 minutes. That'll give you enough time that small changes in timing won't be a big deal but not so long as to be too tedious.
A foot switch operated timer is useful.

I'm right-handed, and so I pick up the stack of film with my left hand. All of the sheet are emulsion down. I take a sheet with my right hand, hold it and inch or so over the water bath, using my little finger to feel the surface of the water, and drop the film straight down. It'll make a nice plop if you do it right. You don't want and edge shooting down and scratching the film below it, although keeping the film emulsion down minimizes the danger of this. Once the film is floating on the top of the water, I use the little finger of might right hand to push it gently down. Repeat. Note that my wet finger never touches the dry film.

Once all of the sheets are in, I gather them together in the lower left corner, all orientated the same way. Take the bottom sheet, and pull it out away from you, pulling it up and out of the solution and plopping it on top of the pile. Repeat for each sheet +1. So if you have 6 sheets, do this 7 times. Now turn the whole stack 90* and repeat.

If I remember rightly, this was Fred Picker's recommended method. It's worked well for me.

RichardSperry
22-Jul-2012, 01:06
The best price I have found on Nitrile gloves is Costco, 400(200 pairs) for $20.

Some of the old timers here might say they are for pussies, they've been sticking their hands in photo chemicals for decades. "With no ill effects". They can get pretty mean spirited and delusional here on the boards when they forget to take their Sinemet.

premortho
22-Jul-2012, 11:16
If at 74 I qualify as an old timer, well...so be it. I've never developed metol sensitivity, but others have. I don't see anything wrong with using gloves...and I don't even know what Sinemet is.

Bill Burk
22-Jul-2012, 11:58
I've recently discovered 2/3 stop less than rated speed from tray processing TMY-2 in stacks of 6, D-76 1:1 for 13 minutes at 68-degrees F.

I seem to get EI 250 instead of 400.

Many people who perform film tests arrive at lower EI than rated, but the reasons for the lower rating is not commonly discussed.

I believe my significant factor is that development in stacks "starves" the film of fresh developer. I think this affects the speed.

I like the quality of the negatives, and I do not need speed. Investigation continues but I wanted to give a heads-up that tray processing in stacks may lead to lower film speed...

Leigh
22-Jul-2012, 12:02
Hi Bill,

Suggestion, if I may...

Develop ONE sheet using your standard process, and compare the results with two-, three- and four-sheet runs.

- Leigh

Bill Burk
22-Jul-2012, 12:12
Hi Bill,

Suggestion, if I may...

Develop ONE sheet using your standard process, and compare the results with two-, three- and four-sheet runs.

- Leigh

I will. And I will also do a run in D-76 straight.