View Full Version : Need your tips for my Open Tray Process

1-Sep-2009, 15:08
I develop my 4x5 film in open trays (typically Ilford FP4 in Rodinal or D-76), and I’ve noticed scratches on the emulsion that are caused, I think, by the agitation process (lifting sheets from bottom to top).

I enjoy developing film in trays – I’d like to stick with it. My plan for now is to alter my agitation process in hope of better results – but first, I’d like to ask the darkroom experts whether I’m overlooking anything.

I usually develop only 3 sheets at a time – so I don’t think I’m speeding through the process, putting sheets at unnecessary risk.

What’s more, when I develop one sheet at a time – or perhaps two – I rarely see these puzzling scratches. :confused:

As Ansel Adams suggests below, I develop my sheets w/ emulsion side up, and I wonder if I’m simply not being careful when, during agitation, I lift bottom-most sheet to the top – that is, I might be scratching the emulsion with the sharp corner of the sheet above it.

In “The Negative,” Ansel Adams instructs:

“Then take the films to be developed, emulsion side up, gently fan them so each can be individually handled (hold them only by the edges). You can then place them one by one in a water bath, pressing each down under the surface.” (I presume this holds for each step in the development process.)

It leaves me curious whether emulsion side down is actually the safer option. I remember such a recommendation from “Using the View Camera,” where author Steve Simmons says:

“Set your timer for the longest development time required, and move the first sheet of film into the developer tray putting the emulsion side down [emphasis by author]. This is to avoid scratching the emulsion side of the film during the agitation process.”

Yet doesn’t this method have its own risks? I don’t think Simmons mentions any. Seems to me that a sheet with emulsion side down might suffer damage from the bottom of the tray – or perhaps from one’s finger-nails or finger-tips, as one places them under the sheet to lift it. And does either method create additional risks I’m not aware of?

Thanks for your ideas, tips, and hints…

1-Sep-2009, 15:27
I always found that emulsion down was far less scratchy for me. The problem is that the emulsion sticks to the bottom of the tray and it can be a PITA getting a finger under it. Helps to have very smooth plastic trays with raised bumps on the bottom.
If I ever start tray developing again, think that I'll get one of those plastic things which holds 4 sheets of film in their own compartment -- I forget what it's called -- The Slosher, maybe?

Drew Wiley
1-Sep-2009, 15:34
You need to be especially careful not to catch one sheet with the corner of another.
Here's how I do it. I use oversize dimple-bottom stainless trays, and wear powder-free
textured nitrile surgical gloves (so no fingernail issues), always emulsion up. The bottom sheet is lifted completely away and then over, then the entire stack is rotated
90-degrees, repeat evey 30 sec (an oversimplified explanation). Avoid temps over 75F,
or better yet, dev at 68F. You also have to be careful handling the film before it enters the solutions (I always prewet). Some films scratch easier than others, but I
can personally develop up to a dozen sheets of 4x5 at a time without scratching. But
you also have to be conscious of airbells between sheets, and some films like ACROS
are quite susceptible to this problem, so I only develop six at a time.

1-Sep-2009, 16:49
I usually used tanks and SS hangars. No scratching. If processing by tray I never processed more than one sheet at a time and collected them in a water holding tray for hypo clear/washing/toning. Tedious? Yes. Time consuming? Yes. Worth it? Depends on the image.

1-Sep-2009, 17:43
hi heroique

i always process in trays and never have problems with scratches ..
but ... i never process as few as 1 or 2 or 3 sheets of film ..
i don't worry about emulsion down or up, i put in water first
and make sure all the films are separated.
i have both hands in the water ( or developer or .. ) one is under the stack keeping
everything together and up front
the other grabs the bottom film against my fingers and pulls down and back and out
the film that is pulled out is put upside down on the stack and pushed down
and never touches the edge or the stack of film.
and i repeat ... for 8 or 15 or 20mins depending on what i am using as a developer.
i do this for anywhere between 8 and 30+ sheets of film at a time, and never
have trouble with scratches ( 16 years ) ...
i guess i don't worry about it, and it helps.

i used to use hangers, but i had a few bad ones in the bunch
( that i couldn't segregate from the pack )
and they marked up important film i processed for a job.
good thing the buildings weren't demolished ( yet )
i was able to go back up and reshoot the 2 days worth of film the hangers ruined ...


1-Sep-2009, 18:01
Heroique - solve your problems by switching to BTZS tubes.


Robert Oliver
1-Sep-2009, 18:10
love my slosher tray.

MIke Sherck
1-Sep-2009, 18:52
Here's how I do it: I mix a gallon of D-76 at a time in a 1 gallon container, then immediately decant into four 1 qt. containers, filling them to the brim and capping tightly. Developer stays fresh for quite a while this way. I try to use an entire 16 oz. bottle at a time in order to prevent oxidation, so sometimes I delay developing until I have enough film to use or almost use the developer's capacity: 16 sheets of 4x5, 4 sheets of 8x10, each roll of 120 or 35mm counts as a sheet of 8x10, etc. The reason I do this is to ensure adequate depth of solution in the tray (for sheet films.) I've noticed that when the amount of developer in the tray is too low, I get more scratches.

For sheet film, I use D-76 1:1 -- 16 oz. of developer and another 16 oz. of water. This gives 32 oz. in the tray and that's great for the 8 sheets of 4x5 I usually develop at a time. As it happens, I prefer TMX and TMY for 4x5 and Tri-X for 120 and 35mm. Since Tmax wants absolutely fresh developer, while Tri-x is more tolerant, I develop the Tmax first in trays, then any roll film up to the capacity of the developer.

I develop sheet film emulsion side down: I discovered that this plus having adequate solution in the tray has pretty much solved my problems with scratches. I'm careful about laying the film shuffled from the bottom of the stack onto the top so that a corner doesn't gouge into the sheet below. My home-made film washer keeps the sheets separated: when I used to just wash sheet films in trays, I got the occasional scratch, although I believe that the wash in trays was more efficient.

Robert Hughes
2-Sep-2009, 11:33
Working on my bathroom sink, I develop with D-76, full strength (8 min @76F), 2 sheets 4x5 at a time in an 8x10 tray, emulsion face up. On one hand I wear one surgical glove (to stroke emulsion) and a heavy duty glove on the other that's easy to remove for dry sheet handling. When moving from wash -> developer -> wash -> fixer I keep the sheets separated by a finger between sheets, and do my best to avoid nicking emulsion with the corner of another sheet. Lately, my technique has improved to where my emulsions are pretty clean and nick-free in addition to being evenly developed - I'm a happy darkroom tech!

David Karp
2-Sep-2009, 12:11
When tray processing, I use a slosher. I learned about this from John Sexton. It is a plexiglass holder that has vertical dividers to hold the film in place, with holes in the bottom to allow developer to pass through. Unfortunately, I won't be able to take a photo of mine until tomorrow, or even Friday. You can build them yourself, or purchase one from Photographer's Formulary (I think). Mine will process 6 sheets in 11x14 trays. I put the film in emulsion side up.

Each sheet is kept separate, no worries. Just lift up the slosher, let it drain, and then move it to the next tray.

Louie Powell
2-Sep-2009, 12:17
I use a slosher tray, and process emulsion side up. The only thing that ever touches the emulsion is chemistry, and I never get scratches.

David Karp
2-Sep-2009, 12:23
Here is a photo of the Photo Formulary "Slosher"


2-Sep-2009, 13:48
[…] I never have trouble with scratches ( 16 years ) ... i guess i don't worry about it, and it helps. […]

Now that’s a track record to shoot for…

All these suggestions are helpful – many I hadn’t considered. Lowering the development temperature was just one simple example. I presume that allows one to work with a cooler, harder, less-vulnerable emulsion.

I’ve been skeptical about surgical gloves since I thought the reduced sense of “touch” would complicate the sensitive handling of wet sheets. But your practical tips suggest otherwise. Plus, covered fingers wouldn't raise the chemical temperature so much. And they'd enjoy better protection. Worth a try.

Or … perhaps this “Slosher” (photo below) would eliminate a need for gloves. I was surprised by all the votes of confidence below. Looks like the Slosher’s dimensions are 11”x14.5”. It would fit inside trays of mine whose bottom dimensions are 13”x17”. That means mixing more chemicals than I usually do – a small price to pay to eliminate scratches. A very interesting item. Are there drawbacks? Even with emulsion side up, can “sloshing” scuff or abrade the film’s bottom (non-emulsion) side? My traditional handling has never hurt the non-emulsion side.

[…] If I ever start tray developing again, think that I'll get one of those plastic things which holds 4 sheets of film in their own compartment -- I forget what it's called -- The Slosher, maybe?

love my slosher tray.

When tray processing, I use a slosher. I learned about this from John Sexton. [...]

I use a slosher tray, and process emulsion side up. The only thing that ever touches the emulsion is chemistry, and I never get scratches.

2-Sep-2009, 13:54
I would try the slosher, but buy two of them. Use the first one in the developer and set the other in the stop. That way you can keep track of up to six separate film development times and pull the individual sheet from the developer slosher and place in the stop slosher. Then simply move the stop slosher to the fixer, to hypoclear, etc. Do the process emulsion side up. You will not have any scratches. The downside is the use of somewhat larger volumes of chemistry and the need for more sink space than small trays. Once the film is in the fix you can turn the lights on.

I prefer BTZS tubes for the developer stage so that the lights can be on. Also, the tubes allow small volumes of developer and even different developers/dilutions for individual sheets of film if desired.

Robert Hughes
2-Sep-2009, 14:04
I prefer BTZS tubes for the developer stage so that the lights can be on.

Lights? What are these things of which you speak?:confused:

David Karp
2-Sep-2009, 16:05
I have not had problems with abrasions on either side of the film from my slosher.

It is home made, and I beveled and sanded the holes until they were smooth. The plexi base is smooth. I sanded and rounded the edges and corners of the dividers. The emulsion side touches nothing but liquid. It is more like developing 6 single sheets at once.

I have been developing with rotary processing lately because of time, space, and volume of film consideration. Given the choice, I think I would still prefer using the slosher in trays, as this seems to give me the very best results.

You just have to make sure that you don't put two sheets in the same divider. I have almost done this a few times, but have always caught it before dumping the film in the developer.

John Sexton created his slosher (and coined the name) for situations where he is doing semi-stand development in situations where he needs extreme compensation. Many of us have adopted them for standard film development.

Do a search for slosher on this site, and you will find a lot of information.

Louie Powell
2-Sep-2009, 16:50
I also use rubber gloves - skin will absorb chemicals, whereas rubber doesn't, thereby minimizing carryover of developer into the stop and fixer.

I use HC110 dilution H. That requires that I essentially double the development time. The result is more even development, and minor timing errors are even less significant.

I tend to standardize as much as possible, and I try to group negatives for simultaneous processing in a way to minimize variations. Occasionally, the need to get film developed forces me to process one or two N-1 sheets at the same time as a group of N sheets. I have a couple of small trays of plain water that I use as holding tray- at the shorter N-1 time, I transfer the negatives requiring that special treating to the holding trays, one negative per tray. then, when I have finished development of the rest of the negatives and have moved the slosher to the stop bath, I transfer those negatives back to the slosher. I use a plain water stop rather than an acid stop.

Film stays in the slosher from the point when I take it out of the storage box for processing until it has been developed, fixed and washed and is ready to be hung up to dry. I intentionally try to avoid handling it any more than necessary. Handling film is the best way to cause scratches.

Ed Pierce
3-Sep-2009, 09:32

I believe you are correct that the source of the scratches is probably from catching the corners of the sheets above while pulling out the bottom sheet. When I tray process, I lift the whole stack with one hand and peel off the bottom sheet with the other.

It also helps to prop up the back of the tray so that the films naturally stay on the side closest to you.

My experience has been that some film/developer combinations seem to be more likely to produce scratches than others. I don't recall ever scratching a txp neg in hc-110, and quit trying bergger film in pyro because of the scratches.

I've always run them emulsion up with good results. Just be sure never ever touch the emulsion...always just the edges and the back. And don't rock the tray...good way to get scratched.

The only drawback I know with the slosher is you need a lot of solution. You also need a lot of space if you want to move the slosher from tray to tray, which is easiest. My sink is only 6', which only fits 4 11x14 trays, but I need 5.

If you're going to make the investment, I would recommend the bzts tubes. But I think with care and practice you can succeed with just the trays.

3-Sep-2009, 10:48
I've never processed multiple sheets of film using the stack and rotate method. It does often cause scratching especially during the development stage since the emulsion is softest and at its most vulnerable. If you really want to risk it to save time I suggest you develop one sheet at a time and allow them to stack up in a acid hardening stop bath. Then fix and wash using the stacked method. Hardening the emulsion before stacking minimizes (does not eliminate) scratching. But even this is not a good procedure, IMHO, because stacked film doesn't wash or tone as thoroughly/evenly as separated sheets.

But ehh... I'm a paranoid SOB.