How much chemical do you use?

jlpape · Jan 19, 2008

I I have a Paterson 2 reel tank that states 290ml is required for 1 roll of 35mm film. I placed that amount in the tank and it just covers the reel (no surprise here). My question is if you really should put in more than the minimal amount to have enough chemical present to properly develop the film (i.e. small amounts get used up and give inconsistent results).

paladin1420 · Jan 19, 2008

jlpape said:
I I have a Paterson 2 reel tank that states 290ml is required for 1 roll of 35mm film. I placed that amount in the tank and it just covers the reel (no surprise here). My question is if you really should put in more than the minimal amount to have enough chemical present to properly develop the film (i.e. small amounts get used up and give inconsistent results).

I have also been using a 2 reel Paterson tank. If you're developing two rolls at once, it's hard to use too much more that 290ml per roll, becuase that just about fills the tank.

When I'm developing a single roll in that tank, I'll use a bit more that 290, not because I think 290 is not enought fluid to do the job, but becuase I worry that if the tank is not precisly level, the top of one side of the reel might not be fully submerged.

I haven't had any problems.

Trevor Crone · Jan 19, 2008

As a matter of course when using Paterson System 4 Universal tanks I use a min. of 350 ml for 35mm film and 600ml for 120 film.

This is to allow for possible upward movement of the reel even with the retaining clip in place, and to prevent uneven edge development caused by 'frothing' of the developer.

I do not add a wetting agent to the developer.

Snapshot · Jan 19, 2008

I use 300ml for each roll of film or 1,000ml fir 3 rolls using the Paterson tanks. Never had a problem with insufficient solution.

David A. Goldfarb · Jan 19, 2008

For most normal developers you should be okay. If you use very dilute developers like PMK or Rodinal 1:100, you might want more, like 500ml per 35mm roll.

Admbws · Jan 19, 2008

My tank (not a Patterson) also specifies 290ml, but I usually round it up to 300ml to make mixing the right quantities of chemical that bit easier to calculate.

You don't specify which developer you are using (I only have experience with D-76/ID-11 and DD-X), but assuming you're mixing to the "standard" recommended dilution, don't worry about there not being "enough" developer in that one shot; there is more than enough for one roll - in fact, I frequently develop an extra roll in the same shot with no problems.

DarkroomExperimente · Jan 19, 2008

I now use 30ml in a film container when developing a single frame of 35mm film from homemade cameras made out of film containers...works great, and it's kind of amusing too

BobNewYork · Jan 19, 2008

I'm with Snapshot. 300 ml per 35 mm, 500 ml per 120, 1,000 ml per 3 tank and 1,500 ml per 5-tank. I never use less than 150 ml of stock per film. Never use less than 5 ml of Rodinal per film. No problems in 25 years. (I probably just jinxed myself here!!!)

pentaxuser · Jan 19, 2008

You can get away with 240ml with a Jobo. There's an argument that say that more than just enough to cover the reel prevents proper agitation. Certainly in the Jobo the specified amount of 240 takes the liquid to the top of the tank and does seem to restrict proper agitation.

pentaxuser

GeorgesGiralt · Jan 19, 2008

Hi !
It depend on the product you use. Take Xtol for example, Kodak state that you should use 100 CC stock per 135/36 or equivalent surface. If you use it 1+3, you are with 400 CC for one film. If you go to PMK you need about 500 CC at 1+2+100 to do one film. so you'll be overfilling the tank with 2 films in it....
Of course, this is not a problem with Paterson tanks and hand inversion, you can take a 5 reel tank and put only one reel into it, but when you plan to use a Jobo CPE2 processor with 600 CC maximal capacity (in order not to stress the motor) you are limited to some products or a single film at a time...
Of course Rodinal (6 cc minimal concentrate per film) or HC110 are different beast !

cao · Jan 19, 2008

Trevor Crone said:
As a matter of course when using Paterson System 4 Universal tanks I use a min. of 350 ml for 35mm film and 600ml for 120 film.

This is to allow for possible upward movement of the reel even with the retaining clip in place, and to prevent uneven edge development caused by 'frothing' of the developer.

Something to consider as an alternative is having some lengths of PVC tubing to take up the slack at the top. An eBay seller shipped me a pen packed in a PVC tube once, and by nice coincidence, the tube closely matched the shaft diameter of my Paterson tanks, so I chopped it up into short spacers, and, voila, no more rising reels.

I wind up using 600ml for 120 film anyhow because I use XTol 1:2 with two rolls on a reel with a minimum of 100ml stock per roll. I still have a couple of rolls with a thin edge where the reel rode up the shaft prior to my using PVC spacers.

Trevor Crone · Jan 19, 2008

cao said:
Something to consider as an alternative is having some lengths of PVC tubing to take up the slack at the top. An eBay seller shipped me a pen packed in a PVC tube once, and by nice coincidence, the tube closely matched the shaft diameter of my Paterson tanks, so I chopped it up into short spacers, and, voila, no more rising reels.

I wind up using 600ml for 120 film anyhow because I use XTol 1:2 with two rolls on a reel with a minimum of 100ml stock per roll. I still have a couple of rolls with a thin edge where the reel rode up the shaft prior to my using PVC spacers.

Thanks Cao.

I've just started testing with just spiral agitation and to abandon the inversion method altogether. I use PMk pyro and Pyrocat-HD; so far the results have been excellent and very consistant. Agitation is continuous for the first minute with 5 second spiral agitation every 30 seconds thereafter.

dancqu · Jan 19, 2008

jlpape said:
My question is if you really should put in more than the
minimal amount to have enough chemical present to properly
develop the film (i.e. small amounts get used up and give
inconsistent results).

Solution volume and amount of chemistry present are
two different but interrelated matters. For example using
Rodinal at 1:100 dilution only 2.9 ml of the developer are
present; a questionable little amount. At twice the
volume same dilution 5.8 ml are present; plenty.

D-76 is another matter. At 1:1 dilution there is plenty
of chemistry. Perhaps 1:3 enough. I use chemistry very
dilute and so use solution volumes greater than minimal.

So it might be thought there are two minimal limits;
a minimal solution volume, and a minimal amount of
chemistry. Dan

jlpape · Jan 21, 2008

Many thanks to all that replied. Great idea to use the tubes to prevent the reels from slipping during development.
Jim

Cor · Jan 22, 2008

jlpape said:
Many thanks to all that replied. Great idea to use the tubes to prevent the reels from slipping during development.
Jim

I have read somewhre (can't remember were) that, when you use a 2 reel tank of Patterson or Jobo, and only use one reel to process say 1 35mm film, you better add an empty reel. I think it was to prevent excessive turbulence, but it will also avoid that slippage problem mentioned..
I always try to use the smallest tank possible for processing film, and if not possible (Jobo) add an extra empty reel to the tank.

Best,

Cor

Rick Jones · Jan 22, 2008

Whether or not you use more than the minimum amount of developer to cover your reel depends on the developer you use and its dilution. The rule I use when experimenting with a new developer or with extended dilutions - use at least 100ml of the stock solution (ex. D76) per 80 sq in of film or 100ml of the lowest dilution for which the manufacturer provides times (ex. Rodinal 1:25). Using these guidelines I don't believe I have ever underdeveloped a roll for lack of active developing agent.

dancqu · Jan 22, 2008

jlpape said:
Many thanks to all that replied. Great idea to use the tubes
to prevent the reels from slipping during development. Jim

I process 120 one reel one liter tank one half liter solution.
The reel goes thud at top end and clang at bottom. Dan

How much chemical do you use?

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