Paper Developer Exhaustion

[M Carter]

I'm finding that my B&W print chemistry generally has far longer life than the labels suggest.

I don't like to pour out chemistry that may still be fine, and I'll reuse unless I'm doing a big print or something special, final, etc. But for dialing in a print, I've had great luck storing chemistry far longer than the instructions/data suggest. For instance, I make plain hypo for bromoils and lith. It's supposed to age quickly in the tray and have pretty limited print count. Yet I can bottle the stuff and use again and again, for sessions days or weeks apart. (I'll get to the point but to avoid being dunce-capped) :

When my developer is fresh, I usually snip a piece of the paper I'll be using, expose it to room light and develop to full black. I keep this handy as a black reference.

Then, under safe lights, I fold a scrap of paper so one half can sit in the fixer for three minutes. I turn on the room lights, and develop the scrap. A full black half against a pure-white half suggests my fix and dev are doing fine.

If I find it "feels" I'm having trouble hitting full blacks on a print, I'll compare to my full-black test scrap and toss a little more working solution in the dev tray, and test a new scrap for blacks.

So... my question - what actually are the symptoms of exhausted developer? Longer times or density loss? Anything to look out for?

I feel my fixer test is legit, especially since I test final prints for silver and hypo. I use indicator stop, and since I know of no way to test HCA, I dump it at the end of every fiber session.

(For the record - I'm really trying to dial in my printing and learn some masking techniques, so I tend to do all sorts of tests, often with cheap adorama RC paper. When I print a final or something I want to keep or give away, I may mix fresh chemistry - but I always do residual silver and residual hypo tests on prints I intend to keep. Yep, sometimes they do go back in the wash... that's what the test is for...)

 

[Sirius Glass]

When print developer is exhausted the image either does not show up or only shows up part way.

 

[snapguy]

heavy

Heavy breathing?

 

[M Carter]

Thanks guys - hadn't thought of fogging - I'd guess that's a product of extended time in the weaker developer?

 

[Gerald C Koch]

Capacity estimates are based on what would be expected from the average user producing prints of average density When print developer nears exhaustion you may notice that it becomes harder and harder to get good blacks. Being miserly with developer is a false economy since paper is more expensive.

 

[M Carter]

Capacity estimates are based on what would be expected from the average user producing prints of average density When print developer nears exhaustion you may notice that it becomes harder and harder to get good blacks. Being miserly with developer is a false economy since paper is more expensive.

Yes, that's why I keep a strip handy showing what the full black density of the paper is capable of. Different paper finishes can appear more or less black, so I usually start a printing session with a black strip and a fix test.

 

[Mick Fagan]

One thing I found out the hard way, is that chemistry usage climbs by about 50% once you switch from RC paper to RC free fibre based paper.

In time, you will find your level of chemical exhaustion using whatever chemistry and paper suits you. If you switch from doing mostly RC paper to fibre paper, roughly halve your estimated throughput. On the other hand you will almost double the square metre per litre capacity, if you switch from fibre to RC coated paper.

My experience is that paper developers get exhausted more quickly with certain types of papers. A sort of rule of thumb with B&W I use, is the time a paper takes to fully develop in the developing bath. Papers that take around 3-4 minutes to fully develop, exhaust developer chemistry demonstrably quicker, than papers that take 1½-2½ minutes to fully develop. I’m not talking about developing solution being absorbed by the paper either, which is an issue in itself.

Mick.

 

[Doremus Scudder]

Yes, that's why I keep a strip handy showing what the full black density of the paper is capable of. Different paper finishes can appear more or less black, so I usually start a printing session with a black strip and a fix test.

Better is to contact print a step wedge on several strips of one grade of paper for the same exposure. Develop one in fresh developer at a standartd time/temp and use the rest for control strips during the session (two or three more is all I usually need). If developer is suspect, then run a control strip and compare. Sometimes the max black is okay, but the developer activity has decreased markedly (meaning you would have to develop longer) or the tonal range has changed (meaning you should toss the developer).

For fix I use two-bath fixing and a conservative throughput estimate plus testing of the last print through the fix for residual silver and hypo. This seems the easiest for my workflow.

Best,

Doremus

 

[Photo Engineer]

Not getting a good black is the second or third sign of a failing developer. The first sign is lower contrast. The second may be longer times or lower blacks.

PE

 

[Ian Grant]

Another is shift in image clour as the bromide level builds up and deloping agents are used up. Most noticable with Warmtone papers. A Metol based develoer will lose contrast and density due to the bromide build up much faster than a PQ developer as the Phenidone/Dimezone is far less susceptible to bromide build up.

Ian

 

[RalphLambrecht]

I'm finding that my B&W print chemistry generally has far longer life than the labels suggest.

I don't like to pour out chemistry that may still be fine, and I'll reuse unless I'm doing a big print or something special, final, etc. But for dialing in a print, I've had great luck storing chemistry far longer than the instructions/data suggest. For instance, I make plain hypo for bromoils and lith. It's supposed to age quickly in the tray and have pretty limited print count. Yet I can bottle the stuff and use again and again, for sessions days or weeks apart. (I'll get to the point but to avoid being dunce-capped) :

When my developer is fresh, I usually snip a piece of the paper I'll be using, expose it to room light and develop to full black. I keep this handy as a black reference.

Then, under safe lights, I fold a scrap of paper so one half can sit in the fixer for three minutes. I turn on the room lights, and develop the scrap. A full black half against a pure-white half suggests my fix and dev are doing fine.

If I find it "feels" I'm having trouble hitting full blacks on a print, I'll compare to my full-black test scrap and toss a little more working solution in the dev tray, and test a new scrap for blacks.

So... my question - what actually are the symptoms of exhausted developer? Longer times or density loss? Anything to look out for?

I feel my fixer test is legit, especially since I test final prints for silver and hypo. I use indicator stop, and since I know of no way to test HCA, I dump it at the end of every fiber session.

(For the record - I'm really trying to dial in my printing and learn some masking techniques, so I tend to do all sorts of tests, often with cheap adorama RC paper. When I print a final or something I want to keep or give away, I may mix fresh chemistry - but I always do residual silver and residual hypo tests on prints I intend to keep. Yep, sometimes they do go back in the wash... that's what the test is for...)

weakening blacks are a sign of developer exhaustion.As long as you get good blacks,developer can be reused.That said,fresh chemistry makes the best printsand cuts down on frustration.

 

[MattKing]

Not getting a good black is the second or third sign of a failing developer. The first sign is lower contrast. The second may be longer times or lower blacks.

PE

Based on this, I would suggest a contact print of a step wedge would serve as the best "control" standard.

 

[Photo Engineer]

I do that for critical work, and in fact, used it as the definitive release test for the final Liquidol formula. It is quite quantitative.

PE