pmk and rollo pyro with hp5+ and delta 100

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I will be using BTZS tubes to develop 8x10 HP5+ and 4x5 delta 100 and possibly 4x5 delta 400. Need starting times for PMK and the newer version rollo pyro. Ihave a densitomer, but it cannot read the pyro through the pyro stain. I have tested via darkroom innovations, but my times for a "normal" negative would be less than 4 minutes. The dilution I used was the recommended 2:4:100 for the rollo pyro. Would appreciate any info especially if anyone has used the rollo pyro at a dilution of 1:2:100. I also think I can get away with using just plain old PMK in the tubes since I hear it doesn't oxidize as much as fast rotary systems. I dont mind testing, but I'd rather be out shooting and fine tuning. Thanks.

-- lawrence suarez (lskjs@gateway.net), February 05, 2000

Answers

I don't know if this will help you: Delta 100, 120, @ ISO 80, in PMK, 1:2:100, small tank, 9 - 10 minutes @ 70F, agitation 5 sec per 30 sec.

-- Peter Hughes (leo948@yahoo.com), February 06, 2000.

Wild. Your times are almost identical to mine, which I find wierd because my times are usually so much different with PMK...

-- shawn gibson (SeeInsideForever@yahoo.com), February 06, 2000.

I have been using PMK only a short while, and I've never heard of this newer version, rollo pyro. Could someone inform me of its differences/improvements? Thanks!

-- Courtney Keane (cykeane@aol.com), February 06, 2000.

Me neither. Ed?

-- shawn gibson (SeeInsideForever@yahoo.com), February 06, 2000.

rollo pyro has I believe citris acid in as an antioxidant to prevent oxidation due to the constant agitation associated with Jobo processors. Apparantly the most pyro formulations quickly oxidizes in the processors reducing their developing action/.

-- wdnagel (wdnagel@home.com), February 07, 2000.


rollo pyro has I believe citris acid in as an antioxidant to prevent oxidation due to the constant agitation associated with Jobo processors. Apparantly, most pyro formulations quickly oxidize in the processors reducing their developing action/.

-- wdnagel (wdnagel@home.com), February 07, 2000.

I had never heard of Rollo Pyro, but I did a search on the internet and came up with some information. It is specially formulated for use with Jobo tube processors.

Part A: 400ml Distilled water 7.5g Metol 10g Sodium bisulfite 75g Pyrogallol 5g Ascorbic acid (Vitamin C) 7.5ml Potassium bromide solution (10%) (equal 0.75g) 2.5g EDTA-Na4 add water to make 500ml

Part B: 950ml Distilled water 150g Sodium metaborate

Working solution: 2 Parts A + 8 Parts B + 100 Parts water Some developing times at 220C (rotation speed 25 rpm): FP4+ (6.0 min) HP5+ (6.5 min) TMax100 (6.5 min) Lotus/Bergger BPF200 (6.5 min)

-- (edbuffaloe@unblinkingeye.com), February 07, 2000.


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