Pyrocat-HD vs MC Vs. Rollo Pyro / ABC+ for use in Jobo

[Tim V]

Hi all,

I asked this in another thread, but thought it best to start a new one to address the topic and keep the other one on track.

Anyway, I have a new CPP-3 landing soon and plan to use it, among other things, for processing 8x10" sheet film in a 3005 expert drum. Up until now I have been using PMK and processing one sheet at a time in trays. I have been very pleased with the result, but have read many times that PMK doesn't play so well with Jobo / rotary processing. From my reading here and elsewhere, it seems Pyrocat-HD is the most used pyro staining developer in this case, but I also see there is the option of the MC variant and Rollo Pyro / Photographer's Formulary's ABC+ Pyro (which I've read multiple times is based on PMK.)

My questions re. the above options are really as follows:

1: Which is the most reliable when using with a Jobo? (The differences between HD and MC seem greater film speed with the later, and perhaps shorter development times? ABC+ seems a bit more complicated with the prebath etc?)

2: Which will give me a stain that is similar to PMK, with close printing characteristics when using VC fibre papers?

3: Recommended developer solution per sheet with these developers seems to be a minimum of 250ml, and in a fully loaded 3005 drum this equates to 1250ml. I understand that this is pushing the limits of the motor and especially the load capacity of the lift. Would people recommend doing a one bath development with this much developer solution, or instead splitting the development time into two parts, each of equal time using 1000ml? (e.g. 5min with 1000ml, dumping, then another 5min with 1000ml.) I also wonder if 1000ml is simply not enough solution to immerse the sheets in the drum quickly, and might result in streaking etc?

4: My reading is that with all of these developers, it's best to use minimum rotation speed and to give at least a 5min presoak–filling and dumping the water several times. Sound good?

5: Lastly, I'm shooting mainly HP5+, so any specific times / tips for Jobo processing with these developer / film combinations appreciated!

Thanks for your time,

Tim

[Pere Casals]

Tim, you may find ample information here: https://unblinkingeye.com/Articles/PCat/pcat.html by Sandy. This is 1st quality information.



1) Any one containing an antioxydant, Ascorbic/Vit C , Pyrocat MC is better for rotary but HD can also work with slow rotation speed, or by sourcing Nitrogen (or other) in the drum, or replacing developer in the mid of the development.

2) In page 3, https://unblinkingeye.com/Articles/P...at3/pcat3.html it explains that depending on developer the stain may vary in color, so if using variable contrast paper then this has an effect in the contrast.
Brown vs Greener stain is what has a effect with VC, so take a developer with same stain color.

3) No streaking, I guess, development time into two parts IMHO is to source new fresh developer in the second bath to avoid developer oxydation effects in the "general stain", so stain of the fog+base.

4) Minimal rotation is always good, high speed rotation creates additional stain fog (general stain) with stain developers lacking an antioxidant.

[Alan9940]

Hi Tim,

1) I've used Pyrocat-HD in Expert Drums on my CPP-2 for 20+ years without issue. Use slowest rotation speed. I wouldn't recommend PMK, ABC, etc, for rotary processing.

2) if you want a stain similar to PMK, then you'll need to use one of the pyrogallol based formulas. Again, not recommended for rotary.

3) Can't remember the last time I ran a full drum of 8x10's, but I'm pretty sure I used 1L of developer and it was fine. Test to be sure.

4) I use a 5 min water pre-soak and don't dump/refill.

5) Don't use HP-5, but the Massive Dev Chart and other online resources will certainly provide a good starting point.

[Jim Galli]

Can only speak for myself. I started out with PMK pyro (bought the book and followed the religion) and never could solve the edge effects no matter how developed. It's like you had to trim a 3X4 neg out of your 4X5 to get rid of the edge density. I tried everything. Then I switched to Sandy King's PcatHD which is cheaper to make and never looked back. Cheaper, better, easier, almost fool proof (ask me how I know this). I mix it up with complete abandon from stuff I buy in bulk from sellers on Ebay, it sits in the darkroom mixed for months at a time and it's "good to the last drop". I use it in JOBO for sheet film and in a piece of sewer pipe for Cirkut films. YMMV

[Andrew O'Neill]

I used Rollo Pyro in BTZS tubes in the 90's, and it worked well. Stain is same as PMK... but... I didn't like it with HP5. I didn't like the look. I switched to Pyrocat-HD.

[Tim V]

Thanks for your help, everyone.

I've read over the info at The Unblinking Eye. Very informative, although I'm still not sure how I feel about the different stain colour of Pyrocat VS PMK. This is why I started looking at Rollo Pyro, which is a variant of PMK developed for Jobo processing but not suitable for tray processing. It sounds like all three options are viable and it might come down to personal bias or taste, but Pyrocat-HD is the most tried and tested of the three, with more online discussion history to draw from and help problem solve. I should probably follow that path in order to keep things easy on myself... But...

With regards to development time differences between HD and MC, are they effectively the same, or does the MC necessitate shorter time? If MC is formulated to be more suitable for rotary; i.e. it oxidises slower and I don't have to worry about dividing the development bath in two, then I'd just as sooner go that way to try and eliminate processing associated with oxidisation and developer exhaustion from the outset.

I'm still a bit confused though about how much solution to use in a fully loaded 3005 expert drum and at what point I'm stressing the Jobo motor and lift beyond what is reasonable. The maximum capacity of the 3005 drum is 1500ml (Sandy recommends at least 250ml per sheet = 1250ml minimum total,) and I'd be keen to fill to this point to help assure even development. I just wouldn't want to do this if it might result in burning out the motor or stripping gears, etc. I understand I could raise the drum and the lift with my hands, effectively reducing strain on the lift when draining the drum. It's mainly the motor I'd worry about.

If I'm reading correctly though, with 3005 tanks fully loaded with 8x10" film most people seem to develop in two baths of 1000ml, both for equal times? Is this simply as to avoid the effects of oxidisation and developer exhaustion? Do people still do this with Pyrocat-MC, or does it make more sense with MC–due to its differing formulation that reduces oxidisation as well as for economy of use–to simply put 1250ml minimum in the tank and develop in one bath?

Sorry, one million questions...

[Vaughn]

If Jobo says 1500ml is the limit for the 3005, then that's what the processor can handle -- remembering that Jobo says to hand-lift the tank.

I suppose you could use PyroCatHD at 2:2:100 for a shorter time -- you should be able to get away with one fill of 750 to 1000ml.

[Pere Casals]

not sure how I feel about the different stain colour of Pyrocat VS PMK. This is why I started looking at Rollo Pyro, which is a variant of PMK

You will find that Rollo creates a thiner stain than PMK.

You should realize what is the effect of the stain's color.

In VC paper the green stain prints with some lower contrast than the yellow stain, but this effect is modulated by the density amount, as a higer density in the negative it also contains an stronger filter.

You can compensate by adjusting the filtration in the enlarger, with (say) Pyrocat you may want to use a higher contrast grade than with PMK to obtain the same in the mid greys. But, as said, this effect depends on density in each spot, so after you compensate the printing grade you still will have a difference in the scene highlights: with Pyrocat (compared to PMK) hilights will print like if filter grade was a bit lower.

So at the end (IMHO) when burning highlights, with PyroCat, you will end using higher filter grade than with PMK. IMHO this is the difference.

If you find the Rollo stain is too thin... then if you move to a brown stain you would be adjusting two things in the printing: the filter grade to the general exposure, and the grade you use for burning highlights, you would be increasing the grade for both, but you would increase more the grade for burning hights that you did for the mids.

...so for equal results (brown vs greener stain) you need a different grade compensation for highlights than for mids,

[Jim Galli]

Tim, with 5 sheets of 8X10 film I always only use 850ml. The JOBO is a marginal pile of rubbish. But there's really nothing else so I keep on keeping on with them. My current machine has dying motor syndrome. I have to run a while and wait for things to warm up before I put a tank on. It's a complainy whiny lazy terd of a machine. But I love the results and there's nothing else like it. Wish they would build a robust version and re-make the $400 (could make them in China for about $33) tanks. Love the concept. Hate the actual machines. I've replaced the troublesome mechanical reversing switch on both of mine with an electronic version. Most people don't experience the same as me because I use the hell out of mine.

[Alan9940]

Tim,

Development times between Pyrocat-HD and the -MC variant aren't significantly different. I found my times with -MC to be just slightly shorter, but not so much that one would even worry about it. I wouldn't worry too much about straining the motor; over the years, Jobo "beefed" up the motor and I'm sure the latest CPP-3 has the most capable motor. Don't use only the handle on the lift to raise/lower a full tank...especially the 3005! Reach under the carriage the drums spins on and provide more lift with that hand vs the one on the handle. Again, I have only ever run a single bath for either -HD or -MC and never had increased general stain working this way. YMMV, of course. I know others do the "two bath" thing and I'm sure it's for a very good reason. Personal testing will tell the tale as to what works for you.