How long does paper developer working solution last?

[dcy]

I just read in "The Elements of Black-and-White Printing" (Carson Graves 1993) that paper developer working solution only lasts 2 hours...

Really?

I am going to do some darkroom printing tonight. I made all my solutions yesterday, including the developer working solution, which I stored in a thick plastic bottle filled to the brim. I know that developer on the tray has a short life, but I was expecting that I can make the developer on Friday, use it on Saturday, then back in the bottle (to the brim), and then use it again on Sunday, and then toss it.

Is Carson just being a perfectionist, or do I really need to make fresh developer 10 minutes before I start printing? What about the people who 5-hour long printing sessions? Do they stop to make fresh developer twice?

 

[Craig]

Ilford says in an open tray life is "a working day", in a capped container 24 hours. In practice, I find it can last much longer.

You'll be fine using the developer over a weekend.

 

[F4U]

Just do it. 5 ounces of Dektol and 10 ounces of water in an 8x10 tray will give you maybe four 4x5 test prints from a Kodak projection print scale and four 8x10's After that, It'll still develop. but they'll be muddy looking. Dektol 1:2 freshly prepared will let you go maybe a day before using. If not, I'll turning dingy looking and that's how you know to toss it. Only a generation ago, we didn't have computers to ask these questions. We just jumped into the cold water to sink or swim, so to speak. Jump in. you learn quick. Of course back then a 25 sheet package of Kodabromide was $5 maybe. Expensive. Not easy on grocery store bagboy money.

 

[MattKing]

Depends on the developer and how you use it.
But if you develop lots of prints, the activity will change.
And if you leave it open to the air for a long time, the activity will change.
All common commercial developers share capacity and working life in their instructions.
And there are systems that help you maintain consistent activity over long periods of high volume printing.
But for now, just pay attention to how quickly the dark parts of the scene take to start revealing themselves in the tray. If it takes 5 seconds when you start a session, and it is taking 10 - 20 seconds later on, you know that it is time to refresh the developer.

 

[snusmumriken]

If you just want to see what a negative might look like when printed, you can probably tolerate the results of ageing or exhausted print developer. Your developer will still work reasonably well when it is discoloured brown to the extent that you can’t see highlight tones while it is still in the tray. If, on the other hand, you want the best possible print, that is achieved by careful attention to many small details, chemical life/capacity being one.

In my own case, by the time I’m printing, I’ve already rejected 99% of my negatives . So I mix chemicals fresh for every print session and work long enough to make the most of capacity while keeping within the mfr’s recommendations.

 

[koraks]

It depends a lot on a host of factors how long your print developer lasts. There's really no hard & fast time limit to give. You'll have to work out for yourself what works for you (yeah, that story again).

So I can't give a straight answer, but I can give some reflection based on my own experience & practice.

I think it's important to understand the nature of the risk of stretching your print developer. After all, if you know what problems to look out for, you know when to mix fresh developer. What happens with a print developer that's overused or has simply oxidized beyond repair due to old age, is that it simply won't finish developing the print within the pre-determined development time. You'll notice this in the form of a weaker image and particularly weaker blacks in your prints. The darkest area just don't go as dark as they do when you're using fresh developer. So this is the thing you need to look out for.

Sounds simple, but especially if you're just starting out with darkroom printing, I'd recommend making some samples on the paper(s) you use that show the actual dmax of the paper. You can then use such a strip or print as a reference to periodically check if your prints are still coming out OK. The reason is that developer deterioration is a gradual process. Your blacks may start to slip long before you notice if you're not watching closely. Having a known-good reference at hand will allow you to detect this much sooner.

So failure of the print developer is not a black & white situation - it's shades of grey. Literally.

Prints are generally developed to completion, which basically means you develop until there's not visible change in the print if the development time is extended further - within reason. If your determined development time is let's say 90 seconds, then developing for e.g. 120 seconds shouldn't make an appreciable difference. In practice, this means prints are usually developed for a standard time; you determine the development time and then stick to that. I assume this is also how you work.

You can imagine that if your print developer starts to fail, it's possible to simply extend the development time and allow the slow developer to still get the job done. Mind you, there comes a point where the developer simply won't finish and you'll end up with flat prints with weak (often mottled, and brownish) blacks. Until that point (which again is more of a gradual process than a clear cutoff point), you could use @MattKing's suggestion above w.r.t. the time it takes for a certain part of the image to appear and calculate the required development time on that basis. So for instance, using fresh developer, record the time it takes before a certain midtone to appear and divide your normal (known-good) development time by that duration. E.g. if your normal dev time is 90 seconds and the midtone in question starts to emerge at 30 seconds, this would be 90/30 = 3. You now know that by the time you see that midtone pop up, you're at 1/3 of the development time. If you're working with a well-aged developer and it now takes 40 seconds for that same midtone to start building, you know you have to aim for a total of 120 seconds to get to (more or less) the same point as with the fresh developer and your initial development time. You'll find this approach described in literature as "factorial development" - if you search for this term, you'll find it's recommended for instance as a way to get perfect consistency from print to print when printing editions, but it's in principle also possible to use this approach to extend the life of your print developer.

This is not to say I'd necessarily recommend factorial development for this purpose. I mention it as an option, only. For simplicity's sake, I'd consider (especially when starting out) to remove as many problem factors as possible and just mix fresh developer at the start of a session. At the same time and especially during longer sessions, do the reference thing I explained above to spot problems with the developer running out of steam.

From a personal perspective, my approach is different still. I stick to a system that for me works consistently enough. In my case, this involves a pretty standard developer (ID62 general purpose developer) that I mix from scratch as a concentrate. I keep a bottle of concentrate as well as a bottle of working strength solution at hand. The working strength solution I replenish from the concentrate. I never calculated a strict replenishment rate and just replenish liberally. This ensures that I have short development times (generally 1 minute up to 90 seconds for some FB papers) and I rely on the principle of develop-to-completion to allow me some leeway in an exact development time - so I just stick to 60 or 90 seconds and verify at the start of the session which time is sufficient to get the job done. If 90 seconds doesn't cut it, I replenish the working strength developer a little more to boost its activity. The working strength developer goes back into its tightly capped glass bottle at the end of the session where it awaits the next session. The last time I mixed a fresh bottle of working strength developer is about 4 years ago when we moved into our present house. Sometimes there's only one or a few days between sessions. Sometimes there's months between uses. But so far it has never failed.

I've done the same thing with ID68 as well and it works similarly. I mix both the ID68 and the ID62 from scratch as concentrates (click links for formulas on @Ian Grant's excellent website). The reason I DIY mix the concentrates is because in the past I've run into problems with half-full bottles of commercial concentrates that sat around for too long and went dead. Apart from the inconvenience, the waste always bugged me. So I now mix relatively small amounts (typically 500ml) of concentrate/replenisher at a time, which I store in a clear glass bottle so I can tell when the concents start to go too dark (which signifies oxidation).

Again, the gist of all this is to figure out what works for you. I'm not going to say that your scheme of re-using your developer across three consecutive sessions will work. Maybe it will, maybe it won't. I want to encourage you to learn to recognize yourself what's going on and how to proceed. You'll get no fish from me, but I hope I've contributed a piece of the tackle you need to catch your own.

 

[Don_ih]

What about the people who 5-hour long printing sessions? Do they stop to make fresh developer twice?

Some people may mix up some fresh working-strength developer (from their stock solution) halfway through a printing session. Developing prints exhausts developer, so if you are pushing a lot of prints through, the stuff may start to drag after a while. (Developing prints, due to agitation, also speeds up oxidation of the developer.)

Generally, developing times will become too long before developer will start warm-toning your prints. So, watch for that.

I find making prints is a more relaxed activity than developing film. There's pretty much no danger of overdeveloping. You can pour in some sodium carbonate solution if the developer starts to slow down. You can pour out a cup of the working strength developer and pour in a cup of stock solution. You don't need to dump the entire tray. But there's nothing wrong with mixing the working solution just before you start (pour 1/2 litre of dektol into the tray, pour 1 litre of water in after that), make some prints, and dump the contents of the tray. You will get consistent results that way.

But I've mixed Dektol with a spoonful of glycin in it and used it until it was almost black....

 

[dcy]

Well... Once again I failed to produce a good print today, but I am happy to report that I can now recognize the signs of an exhausted developer.

The print on the right was taken relatively early in the session. I was struggling with white marks on the prints. I suspect a combination of dust, and uneven development (perhaps bubbles on the print). Eventually I just had to take a break. Came back a few hours later. I think I resolved the white streaks (dusted the negative, improved the way I insert the paper in the development tray) but I can no longer get the same blacks I was getting at the beginning.

Side note --- This cellphone photo doesn't do the print justice. The print on the right has nicer blacks that this photo suggests. Not spectacular, but better than what this awful cellphone photo would suggest.

 

[dcy]

Prints are generally developed to completion, which basically means you develop until there's not visible change in the print if the development time is extended further - within reason. If your determined development time is let's say 90 seconds, then developing for e.g. 120 seconds shouldn't make an appreciable difference. In practice, this means prints are usually developed for a standard time; you determine the development time and then stick to that. I assume this is also how you work.

I had no idea that prints are developed to completion... Yeah, I print to a standard time of 2 minutes. The developer bottle says 1-2 min, and the book by Carson Graves says to standardize on 2 min and he'll talk about adjusting that in a later chapter.

I figured that development time is not the dominant variable right now so it made sense to leave it in place and focus on other things.

You can imagine that if your print developer starts to fail, it's possible to simply extend the development time and allow the slow developer to still get the job done. Mind you, there comes a point where the developer simply won't finish and you'll end up with flat prints with weak (often mottled, and brownish) blacks.

Thanks. Looking back, I can see that all my previous attempts in the darkroom suffered from exhausted developers. A moment ago I posted my last print of the day, and at this point the print looks really muddy and I simply cannot get the blacks I was getting earlier.

This is not to say I'd necessarily recommend factorial development for this purpose. I mention it as an option, only. For simplicity's sake, I'd consider (especially when starting out) to remove as many problem factors as possible and just mix fresh developer at the start of a session. At the same time and especially during longer sessions, do the reference thing I explained above to spot problems with the developer running out of steam.

Thanks.

I've done the same thing with ID68 as well and it works similarly. I mix both the ID68 and the ID62 from scratch as concentrates (click links for formulas on @Ian Grant's excellent website). The reason I DIY mix the concentrates is because in the past I've run into problems with half-full bottles of commercial concentrates that sat around for too long and went dead. Apart from the inconvenience, the waste always bugged me. So I now mix relatively small amounts (typically 500ml) of concentrate/replenisher at a time, which I store in a clear glass bottle so I can tell when the concents start to go too dark (which signifies oxidation).

My almost-year-old half-full bottle of commercial concentrate doesn't look quite dead yet, but it has developed some nasty-looking precipitates.

I as actually thinking of making E-72 when I'm done with that bottle. Similar to your ID-62, but without Hydroquinone or Benzotriazole and with Vitamin C instead. --- A "PC" cousin of the "PQ" developer you use.

I'm not sure about doing replenishment. But if E-72 turns out to be cheap, easy to make, and long-lived, I could use it "one shot" (i.e. "one session") and remove a variable.