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IanMazursky
13-Jun-2010, 19:31
Hi,

I shot a few HP5 12x20's at my sisters graduation today. Sorta fun but not!
I made some bad rookie mistakes that i haven't made in years.
Pulled the dark slide of an already exposed sheet while the holder was reversed. Damn! That was the start of it.

Anyway, the light was a little bad so i rated the film at 500 instead of 400 to give me a little extra to stop those grads from moving around.
Im processing them in my jobo atl 2200 at 15 minutes, 21c, 50 rpm in the 3063 drum.
Should i add some more time to or will 15' be ok?

Thanks,
Ian

IanMazursky
13-Jun-2010, 22:05
I have another question about PMK in general. My formulary Part B has some crystals in the bottom of the bottle.
I think they were there since i bought them but another part B bottle i have doesn't have them.
Ive shaken it up and they are not dissolving back into solution. The negs seem fine, just wondering if i ignore them?

Drew Wiley
14-Jun-2010, 14:01
If you can't dissolve the crystals you better dispose of it and start a fresh batch. It
means something will be out of proportion. You might seem to get away with things at
the moment, but might not be so lucky the next round! Contrast will potentially be
affected, which is the last thing you need if your negs are underexp in the first place.

Eric Woodbury
14-Jun-2010, 14:21
I had problems with Part B, altho it never affected my development. Now I measure and mix the Kodalk from dry chems every time. 6 grams/liter.

I never got 400 ASA out of HP5+ with PMK, but if you want to increase development make sure there is plenty of developer ( for 12 x 20 you would need about 1 liter/sheet) or do a developer change in the middle of the development time. Also, you can add some extra A part. Adding more B part will increase pH and boost the development a bit, but not much do I think. Always test first. YMMV.

IanMazursky
14-Jun-2010, 15:18
Hi guys,

Thanks for the info. Im using 15ml A and 30ml B in 1000ml of H2O.
Seems to work fine in the jobo. Im just wondering if i should add some more time for the dev cycle to compensate.
Maybe 1/2 stop push but ive never done that before with this film or in the jobo. Any guess on time would be very helpful.
Btw, i am not doing an after bath.

Regarding the solution, i keep shaking it and the crystals are getting smaller!
It does say shake well ;-)

As a side question, Should i be looking into PyroCat HD? Will i gain anything in my jobo with HP5?

Thanks,
Ian

Drew Wiley
14-Jun-2010, 15:53
You're not really pushing the film, but simply adding density to the highlights. You'll
still lose some value in the deep shadow due to underexposure, but shouldn't be a lot.
PMK is fog prone in motorized drum development. You can obviously print through the
fog, but there's a bit of penalty in crispness. Many alternatives exist, including PMK-plus, Rollo-pyro, and the various pyrocat tweaks. You can also add argon gas to the drum to minimize aerial oxidation. Going from pyrogallol to pyrocatechol (as in pyrocat)
will change the color of the stain from greenish-yellow to brown. You'll have to experiment to see if you like this or not. The effect is slightly different, especially with
VC papers.

Andrew O'Neill
16-Jun-2010, 09:46
Pyrocat-HD is better suited for rotary processing (and tray). PMK is better suited for tray development. PMK oxidizes more quickly if you rotary process with it.
For my own experience, an EI of 500 will leave me with very very thin shadows. I expose (for silver papers) at an EI of 250. Alt processes, EI 320-400.