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tank size matter?

Rinthe

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does it make a difference if i develop 1 roll of 35mm film in a small tank that only takes 1 roll of 35mm film vs developing that 1 roll of 35mm film in a larger tank that takes 2 rolls of 35mm film (filling the whole tank with chemical)?
 
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If you use a larger tank, Paterson or similar, and you're using inversion agitation then you just use enough developerto cover the reel, the amount is on the bottom. So no you don't need to fill the tank.

Ian
 
I have been trying to figure this same thing out as I have a few test rolls that I need to develop. I use a Paterson tank that holds 3 35mm films. If you only put enough developer in the tank to 1 film (I think it says 295ml or something) what happens when you invert the tank? Will the film not be left high an dry as the liquid sloshes to the top (now the bottom)?
 
For myself, I always fill my tank (well, not quite completely) with developer. But I use replenished D23, so I am not wasting chemical. I know that does not answer OP's question, but I would wonder about overagitation if the tank were not filled completely. But my fears may be unfounded. I have found since being on APUG that people suggest procedures taught me by old lab rats (some of whom went back to glass-plate era) are wrong.
 
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I'm with Anscojohn. I always fill to the top to avoid exacerbating any agitation problems.
 
It depends how you do your agitation.

In my case, I use continuous roller agitation, so I calculate the amount necessary by determining how much is needed to cover half the reel when it is turned on it's side.

If I went back to using non-continuous inversion agitation, I would most likely want to (mostly) fill the tank. Alternatively, I might consider agitation schemes that don't involve inversion (twirling, or "figure-eight" on countertop).

Remember as well that if you are in the habit of choosing between various dilutions, you can choose a higher dilution to ensure a full fill.

Matt
 

Not a problem. The film isn't out of the developer long enough for it to make a difference, and you're sure to get good agitation. The only thing to watch out for is to make sure the reel doesn't creep up the center spindle. Paterson tanks should have a clip that goes around the spindle above the reels to prevent slippage; but after a while, these clips either go missing or wear out and slip themselves. A rubber band wrapped tightly around the spindle and tight up against the top reel makes a more than satisfactory substitute. It actually works more reliably than the factory supplied clip.
 
The only thing I would be concerned with doing that, is introducing foam and specifically air bells to the film surface. I think it might still be problematic even with Franks method. Personally, I will only use a single reel tank when theres only one roll to be processed. Any more, I will only process one roll at a time for consistancy sake.I have larger tanks, but only use them for single 120 runs. A single roll tank is cheap insurance for quality IMHO.

Rick
 
My tests indicate as long as the film is submerged for rest time between agitations, make no difference.

In fact the best agitaion removes the film from the developer during agitation.

Paterson tanks are particularly nice because the empty space in the top makes for significant developer movement. You never get streaks or marks with a PATERSON IF YOU FOLLOW INSTRUCTIONS.
 

In commercial processing, I was taught when developing reels or sheet film in the 3.5 gal. tank to lift the film completely out of the tank twice during an agitation cycle and allow to drain before returning it to the tank. Never had a problem.
 
Fred is absolutely correct. 4x5 film in hangars is best agitated this exact way also unless you have a nitrogen burst system.

For 35mm, a perfect way is to use a double film tank, two reels with film in the bottom one only, and only enough liquid to cover the film/lower reel. the times are exactly the same a single reel tank. I have done this many times and get perfect evenly developed negs.

It also proves there is no such thing a surge marks or localized overagitation. If inversion in a half full tank does not induce overagitation, nothing will. People who try to make slow gentle agitation to solve an unevendevelopment problem are creating even more more problems.

The large amount of empty space in the top of a Patterson tank does the same thing, by allowing extreme solution movement during inversion. It also is perfect for filling as there is a funnel that makes you fill bottom up and not be spilling developer over the film edge when filling. This actually introduces part of the film to developer earlier than the rest and can really mark the film for concentrated developers and short overall times.

Lowering the film into a prefilled tank accomplishes the same thing as the Patterson funnel. This is the best way to work with a stainless type tank and is the only way to do it as the tanks get larger. That is why larger tanks were furnished with lift rods.

You can safely empty developer through the top up to 4 reel tanks.

Fix does not matter as it is process that goes to completion and stops. Really good agitation is important with fix also otherwise there tends to be an unfixed streak down the center. With a single reel tank, after 2/3 the fix time, I pull the film out completely three times. You can do this in day light as development is no longer possible.
 
Just to add my 2 cents. I just developed a couple of 35mm test rolls in a Patersn tank that holds 3 films. Developed one at a time, 300ml of chems each, inversion style and they came out fine as far as I can see. No air bells (I should hope not with the slapping that tank got) or streaks etc. So, yes it dose work