Do You Re-use Your Chemicals?

[Mark Barendt]

The loss depends on the system, prerinsing for example will keep developer volume fairly steady but it dilutes the working solution, starting dry with developer first there will be losses in volume but concentration stays steady.

For say C41 there are certain amounts of fresh Replenisher that need to be added based on the amount of film that just went through. X-rolls, y-ml

My normal C41 tank volume is 570ml. While the working solution is in the tank I add the proper amount of Replenisher to a graduated beaker, the working solution is dumped out of the developing tank into another container, the "used" working solution is then added to the beaker up to 570 and the rest of the working solution is dumped as waste.

[BradS]

for prints, I mix up fresh working solutions each morning, along with enough chemistry to "top up" the trays throughout the day as necessary, and dump everything out at night.

for films, it really just depends upon how much I have in the back log and how much I plan to do in the near future but, generally, I reuse developer with and without replenishing.
Lately I've been using fresh mixed fixer every day. Doesn't matter if I'm doing one roll of film or ten that day.


(edit: all my comments above pertain to B&W as I don't do color).

[Rafal Lukawiecki]

As I am on a septic tank in rural Ireland, with no community options for spent chemistry collection, I reuse everything as much as possible, within manufacturer's guidelines, except for film developer (XTol 1+1), which is one-shot anyway. Fixer gets tested after each session and, for paper, is rotated in the usual 2-bath way, before, finally, being desilvered. I only do B&W.

[Jim Noel]

Without replenishment developers constantly get less active. This is even true in relatively short printing session, and is certainly obvious with most film developers. Developers are too cheap to take a chance on an important negative being developed improperly. Why save a few cents and waste the cost of a sheet of film?
I do not re-use any developer other than D-23 which has some very unusual and very useful properties as it is used over and over.

[alexn]

Bw chems in a tray i reuse once.. Fixer one shot. E6 chems get 4 runs or 3 weeks use, which ever comes first.

[Cletus]

I use XTOL 1:1 twice - either two rounds of six sheets 4x5, 3 or 4 sheets 8x10, three 120 rolls. I'm beginning to rethink the wisdom of doing this, but I've never noticed any degradation, or inconsistency in the negs between the two batches. Sometimes I'll go up to one week between the two sessions, but I dump the developer if it's much longer than that.

In my early days, before I knew better, (don't know too much more now!) I used XTOL at FS and would process five 35mm reels at a time and reuse as many as five or six times before I "guessed" that the developer might be starting to "get worn out" and dumped it. That was before it ever occurred to me there could be a datasheet somewhere that talks about developer capacity. When I started this B&W adventure off some years ago I had only a basic darkroom book and a wing and prayer!

For prints, I use Dektol and return to the bottle and re-use until it starts to visibly oxidize, which is largely dependent on the length of time spent sitting in the tray. I seldom do more than 15 or 20 prints and 2 to 3 hours per session and probably get 2-4 sessions from a 2L batch at 1:3. Or when development times begin to get long. I develop to completion in the tray, which is normally 2 to 3 minutes, but when the developer begins to reach capacity it begins to take longer for the image to form and there is a visible change in density in the blacks, IME.

Ilford Rapid Fix at 1:9 and use until fixer test determines it's depleted. I use the same batch of fixer for film and paper. I know this is against "policy", but I've not yet seen any adverse results to discourage me from doing this. I also never saw the point in using IRF at 1:4 - not very economical for me - and don't understand the point of the higher concentration.

I guess some of my general chemical reuse practices are not recommended for reasons I don't understand at this point. I've been reading a little more lately though, and may learn something new that convinces me to change some of my ways.

[ROL]

I know this question is rather generic. Say just general BW C-76 (small tank), C-41 and RA-4 processing (rotary tank/drum) in personal use.

It seems some folks re-use the BW chemicals, even the developers. Then most use the color chemical as a one-shot. The labs do not throw them away, but they replenish the liquid.

Then when you do color test printing, do you pour the chemical back to the main container? Or you throw it away and do not want to cross-contaminate the main bottle for main color printing? With the rotary tank/drum, you do not waste so much chemical.

Maybe I answered my own question?

Well, if that question was regarding B/W, unless you're a commercial lab, most individuals use film developers (Rodinal, Pyro's, XTOL) one-shot, paper developers to either oxidation or exhaustion. That differs depending on the particular paper developer and how it is kept. Dektol goes off in open trays in 5 to 6 hours in my lab. It might keep the following day if I kept a lid on it (I don't). I've never printed enough in a single day's session to exhaust it, although I guess it's possible. Covered stock Dektol keeps 6 months. Ansco 130 keeps for months, oxidizing slowly. Read the directions.

I was just going to ask a similar question.

Regarding fixer - I'm currently tray developing and with my slosher, it's meaning I'm having to use about a litre and a half of chemicals to cover the sheets properly, although I'm going to look and see if I can reduce this if only by 250ml. I'm going through fixer and stop like it's going out of fashion at the moment as 1.5l of chemicals means 150ml of fix, 75ml of stop.

Stop - I hear some people just use a water stop rather than a chemical stop? I know there was a few raised voices when it was talked of just using water rather than chemistry. What is the general consensus, if there is one? Is water a good enough stop?

Secondly - temperatures. If I'm storing my diluted, reused fix, it's not going to be 20c exactly when I pour it into the tray. It might be warmer by a few degrees. Is this going to have any significant impact?

Sorry to hi-jack the thread but wanted to add a few additional questions and didn't an almost identical thread would be wise.

Water is not a stop. It won't stop development. It will rinse developer from your film or paper, allowing less developer to carry over to your fix, where developing will be stopped. Acid stops exhaust just like developers, usually with use. I use water "stop" because I use TF4 fix in all processing. Water won't exhaust per se, but should be replaced regularly, ideally to the point of "running" water.

Fix generally oxidizes very slowly, so once again it is a matter of exhaustion. Keeping a conservative tally of films and papers that have gone through your fix, as per manufactures specifications, works well.

Temperatures for B/W are only critical within the manufacturer's specified range. Less so for paper than film. It's really a matter of consistency. Consistent developer temperatures are your main worry, as long as the 'stop' and fix aren't (hyperbolically) freezing or scalding.

[Michael_4514]

BW developer is one shot. I typically use highly diluted Rodinal or HC110.

Indicator stop bath. When the color changes, it's dumped.

Fixer seems to last forever. I have a gallon jug and my typical volume in the tank/drum is from 300 to 400cc.

Color, I reuse all chemicals until I've approached the rated capacity or passage of time. I usually mix 1 liter batches.

All the above applies to film only. I'm not doing prints at home currently.

[Rafal Lukawiecki]

Ansco 130 keeps for months, oxidizing slowly. Read the directions.

That is also a reason why I use Ansco 130 for paper, it seems to have the best keeping properties, especially as stock, remaining stable, and with a fairly good capacity compared to Dektol. I feel it helps me maximise reuse. And I like the look.

[Cletus]

Hmm...Ansco 130, never thought about that one. note to self: look into Ansco 130....