PMK pyro, but no stain

[dario]

Hi folks

I've just used PMK pyro for the first time. I developed a sheet of FP4+ using the procedure set out in the Book of Pyro, but while the image looks fine, there's little or no stain.

I mixed up the stock solutions from a pack bought from Photo Formularly and all seemed to be well. The A solution is a very slight straw colour.

I haven't ever seen a neg developed in PMK, so I'm not sure what to expect. If I look at my neg for long enough I can convince myself that there is a slight yellowish tinge, but that's all.

I presoaked in distilled water, developed for 10 mins with agitation every 15 seconds, washed in tap water for five minutes, fixed in standard Ilford fixer for 4 minutes, returned the film to the developer (which had turned orange during the course of the development) for 2 minutes, then washed for 25 minutes.

What am I doing wrong?

Thanks.

[PhotoJim]

What film? Some, particularly t-grain films, don't stain that much.

I use a water stop and an alkaline fix, which will maximize stain but from what I understand, a standard acid fix should still leave plenty of stain left.

Incidentally the returning-the-film-to-the-developer step has been depracated. I have not done this for years and I still get excellent stain. However, I don't use a presoak; I've never had a reason to do so.

[dario]

Thanks PhotoJim - As I mentioned, it's FP4+ (4x5).

On looking at the neg again and putting it beside negs not developed in pyro, the stain is a bit more obvious. Overall, it's a sort of straw colour, including the film edges, but it doesn't seem very intense. Perhaps it's just a matter of me not knowing what to expect.

I have read about the afterbath being no longer recommended, so might give that a miss in future.

I don't usually presoak films, but Hutchings gives it as a means of avoiding streaking, so as this was my first attempt, I thought I'd better follow his advice. Certainly the neg seems to be free of any streaks or unevenness.

[Ian Grant]

The colour of the stain varies from film to film so there may be stain but you're just not noticing it.

Ian

[dario]

Thanks Ian. I guess the proof will come when I try to print it. :-)

[c6h6o3]

Thanks Ian. I guess the proof will come when I try to print it. :-)

Exactly. Visible stain (or not) on a negative tells you nothing. How the negative prints tells you everything.

[Michael R 1974]

I agree it can be difficult to judge by eye, particularly since the stain is proportional to silver density. It should look somewhat greenish-yellow in comparison to a non-stained FP4 negative. FP4 stains quite well in PMK.

The conventional wisdom is acidic fixers reduce stain. I always used neutral/alkaline fixer with staining developers, but never tried a side by side test with a standard acidic rapid fixer, so I don't know if this is true or not. I just went with the recommendations in The Book of Pyro.

[Klainmeister]

So you made the two solutions.... you need to make the working solution (part A and B) while you do the presoak, otherwise a working solution oxidizes and won't stain well after an hour or two.

[PhotoJim]

Sorry, I missed that you said this was FP4.

FP4 normally stains very intensely. Plus-X stains a little moreso but also has more general stain. I find the stain on both to be very obvious.

If you're tube or rotary developing your sheet film the presoak might be more necessary - you can always experiment. For now I'm tray developing with PMK, or developing 35mm and 120 in standard tanks.

Klainmeister has it right - I'm not sure if you're mixing up your working solution well in advance. You should mix it up immediately before use. I start using it within a minute of mixing it - there's no need to wait. Pour out your water, measure out your A and B solutions (I pour the A into the water as soon as I measure it), and dump the B solution into the A + water as soon as you're ready to develop.

[JBrunner]

1: Skip the "developer after bath". It does nothing but add to B+F.
2: Use an alkali fixer.
3: Mix PMK directly before use because it oxidizes rapidly, and even more quickly under agitation.
4: Make a fat negative to begin with.