PMK - less stain on FP4+ than HP5+

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I just started using PMK pyro on FP4+ and HP5+ 120 size. I did a test with one roll of each with different exposures, etc. as I would with a new film/devo combo.

I developed as per Book of Pyro: 10 min for FP4+ and 13 min for HP5+. Water wash, then Photo Formulary alkaline fixer, two minute dunk in used devo, then 20-30 min wash.

The HP5+ is nearly olive with a slight fog. The FP4+ looks almost normal relative to HP5+, with no fog, a slight yellow-green stain, but much less than HP5+. Compared to Tri-x or Tmax in XTOL (neutral to slightly blue), the FP4+ looks very yellow.

On test prints, to my surprise, FP4+ and HP5+ had very similar grain, perhaps due to greater stain. I used the smae water, dilution, etc. for each roll. I mixed fresh devo for each with one roll in a one liter two roll tank, full of devo. There was possibly a tiny amount (5 ml) more air in the HP5+. In neither was the tank totally full. The only other difference is that I developed the HP5+ roll first, and used that devo for both post-fixing bath.

Anyway, my two questions are:

1)I have heard that faster films stain more. Is this common experience? Doest HP5+ stain more than FP4+ in others' experience?

2) Is it peoples' experience that pyro developed 120 HP5+ and FP4+ have similar grain?

Thanks.

-- Michael Waldron (michael@cadogan.net), August 13, 2001

Answers

Michael, your experience with FP4+ and HP5+ in PMK is perfectly normal. Fine grained films do stain less than courser grained films. And from the description of your procedure, you did everything correctly.

As for the grain of HP5+ and FP4+ being equal, I am suspect. PMK does show fine grain with HP5+, due to the staining. But PMK also yields very fine grain with FP4+. In my experience, FP4+ grain is significantly finer than HP5+ when developed in PMK.

I wonder if you are comparing equal density negatives. If the FP4+ negs are somewhat overexposed, that could account for the grain increase. Also, I think I use 9 min for FP4+, and, like you, 13 min. for HP5+. I don't have my notes handy, but it might be that the FP4+ negatives are a little overdeveloped.

It might also be something as simple as comparing an FP4+ image which has an expanse of out of focus midtones to an overall sharp HP5+ image. All things being equal, FP4+ should show significantly finer grain.

-- Ted Kaufman (writercrmp@aol.com), August 13, 2001.


Thanks for the thoughts above. When I look at the grain with a magnifier, I do see a bit more grain in the sky with HP5+. However, as you noted, it is more in the lower mid-tones that grain is more evident, in part due to the lower density of stain. I guess that I saw less grain than I expected with HP5+.

Thanks again

-- Michael Waldron (Michael@cadogan.net), August 13, 2001.


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