Working solution life . . . Ilford PQ Universal Developer?

DannL · Jan 18, 2006

Another newbie question and then I'll give everyone a breather.

According to Ilford's PQ Universal Developer hand-out (.pdf) it says that the "working solution life" is 24 hours. To clarify (for me) does that mean that once diluted with water 1+9, I have 24 hours to do all my developing, and then that batch of developer is shot?

eumenius · Jan 18, 2006

Yes, that is so - the diluted solutions won't keep long, especially in open trays. But if you make a large batch of PQ working dilution, then pack it in a tight-capped bottle with no air space over the liquid, it would keep longer than a day if unused. I just can't see much sense in diluting too much of stock at once - it's easier to fill a tray, make your developments, and pour the developer away to start the next session with a fresh one. That's the bonus of liquid concentrates, always ready for work.

dancqu · Jan 18, 2006

DannL said:
According to Ilford's PQ Universal Developer hand-out
(.pdf) it says that the "working solution life" is 24 hours.
To clarify (for me) does that mean that once diluted with
water 1+9, I have 24 hours to do all my developing, and
then that batch of developer is shot?

You should take those Ilford instructions as a suggested
method of usage. Those instructions are another example
of the one-size-fits-all type which permeate darkroom
literature.

I for example, do all print processing with one tray using
minimal solution volumes. If I were using Ilford's PQ it would
likely be diluted 1:18, 1:27, or even 1:36 with 3 or 5 minutes
allowed for development. After one print the developer is
dumped and a very dilute fixer goes in. With a very dilute
fixer archival results are achieved in one bath.

So much for instructions. Dan

Gerald Koch · Jan 19, 2006

I use a Metol-hydroquinone developer. If I make only a few prints and I intend to make more in a day or so I may bottle the used developer for later use. I have never had any problems in doing this.

pentaxuser · Jan 19, 2006

DannL said:
Another newbie question and then I'll give everyone a breather.

According to Ilford's PQ Universal Developer hand-out (.pdf) it says that the "working solution life" is 24 hours. To clarify (for me) does that mean that once diluted with water 1+9, I have 24 hours to do all my developing, and then that batch of developer is shot?

The exception to all of this is the use of a Nova or similar narrow slot tank. Effectively 3 or 4 trays standing on end with a thermostatically regulated water jacket around them. Dev and Fix in these have a very small surface area exposed when printing and are covered by hollow plastic tubes at the end of each session.

Chems in these tanks will last several weeks untouched and if printing is done every few days then replenishment ensures that you need never actually throw away the chems.

The pro is that printing is instant and you can do just one or two prints without wasting chems.

The con is that you cannot see the print develop and the expense of buying the processor.

Pentaxuser

Stuart · Jan 21, 2006

Hi Dann
I use PQ almost exclusively and after a printing session if there is still life in the developer I place it into a air tight container which will keep for over a week.
This only applies to RC papper not FB.If useing FB I will only keep the working solution for 1 or 2 days.
It still works after longer periods but I find the blacks in the prints can suffer a bit.
Regards
Stuart.

Diaga67 · Jan 21, 2006

I have a very basic question. How can I tell when the developer is losing it's capability? Is it simply increased development times, or are there other effects on the prints I should be aware of (i.e. blacks suffering as mentioned earlier)? I am very new at this, so thanks for your patience!

Jim

dancqu · Jan 21, 2006

Diaga67 said:
I have a very basic question. How can I tell
when the developer is losing it's capability?
Jim

I'll suggest a method for those who put,
over time, more than one print through the
same tray of developer.

Make 3 or 4 identical RC Grade 2 5 x 7 prints. RC will
fix and wash in a few minutes. At the start of processing
put through a 5 x 7. Every now and then check the developer
with another 5 x 7. IMPORTANT: Observe for first appearance
of the image on the paper and make note of that time. That
is the induction time and is a measure of the developers
activity. Compare. Adjust development time and
perhaps paper grade as needed.

My method of processing obviates the need for adjustment.
The one-tray one-shot method of processing is a good way
to do a few prints. A least amount of very dilute developer
solution is used. No stop and a very dilute one-shot
single bath archival fix follows. Dan

Working solution life . . . Ilford PQ Universal Developer?

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