Re-ordering Pyrocat XX

[George Collier]

I'm finishing off a batch of Pyrocat HD premixed in water from the Formulary. I am close to finding a really good recipe (dilution, temp, time, agitation, etc) for semi-stand with FP4 with tubes.
A couple of questions, if someone can advise:

If I replace with Glycol version, what will it change about what I do, when mixing with distilled water for use? The longer shelf life would be good for me (I'm too embarrassed to say how long I've had the current batch - what can I say, I have other pursuits.)

What about Pyrocat MC? I just read some older posts about it, and it seems like it might be worth a try. I wouldn't mind adjusting the time if there is an advantage over HD. I also use VC paper with an Aristo V54 head, so the lesser stain might result in shorter exposure time (16x20s can be long, even from 4x5))

One other probably dumb question - if I buy either one in Glycol, I would still dilute the same way in distilled water for use, right? I would divide up the original A and B containers into small (200 - 250 ml) bottles for storage, which I did with the current batch.

 

[Thomas Bertilsson]

I don't have any scientific evidence, but I found that Pyrocat-MC in glycol gave me similar results as Pyrocat-HD in H2O, using the same times and dilutions. Nearly indistinguishable.
Someone with more scientific testing methods might chime in to tell me I'm talking out of my hat, but that's what I noticed and I've run with it. Didn't change a thing.
- Thomas

 

[sanking]

I don't have any scientific evidence, but I found that Pyrocat-MC in glycol gave me similar results as Pyrocat-HD in H2O, using the same times and dilutions. Nearly indistinguishable.
Someone with more scientific testing methods might chime in to tell me I'm talking out of my hat, but that's what I noticed and I've run with it. Didn't change a thing.
- Thomas

The results are very similar in terms of contrast when development is the same. That is due in large measure to the fact that the chemistry was balanced to make that so.

However, there are some differences. One is that the color of the stain is quite different. That of Pyrocat-HD is brownish-black, that of -MC more toward yellow-brown. However, the exact color of the stain varies subject to film type and water source, of course. Another difference is that -MC appears to give higher acutance with rotary agitation. I personally use -MC with rotary agitation, and -HD with minimal agitation and stand type agitation.

Sandy Kinig

 

[hka]

I also like to give MC a try. I bought yesterday the chems for it but they send me Triethanolamine (TEA) as a liquid instead of powder. How to handle this. I mean how much ml for how must grams do I add?

 

[Tom Hoskinson]

I also like to give MC a try. I bought yesterday the chems for it but they send me Triethanolamine (TEA) as a liquid instead of powder. How to handle this. I mean how much ml for how must grams do I add?

Harry, I just sent you a PM containing the Pyrocat-MC mixing instructions that I use. I have always used Triethanolamine as a liquid (a viscous liquid!).

 

[gainer]

I also like to give MC a try. I bought yesterday the chems for it but they send me Triethanolamine (TEA) as a liquid instead of powder. How to handle this. I mean how much ml for how must grams do I add?

TEA is by its nature a liquid, and a quite viscous one. I have never heard of it existing as a powder. IIRC, its specific gravity is 1.15 or thereabouts, so 1 ml would weigh 1.15 grams. To be sure, look it up on www.dow.com. I'll check to make sure that's the right web site and will get back here if it's not.

 

[hka]

I came on that because in the recipe stood 8 grams of Triethanolamine. This confused me a little bit. Anyway I mixed up just my Solutions A and B. The A solution is a little yellisch, to dissolve the Potassium carbonate in the B solution takes some time to get clear. Does this sound common? Tomorrow I will develop my first film in Pyrocat-MC. I can't wait to see the results.
Thanks to anyone who helped me to give the right answers on my questions to solve my problems making the first batch.

 

[hka]

This weekend I tested some rolls in my self-made Pyrocat-MC. Therefore I used some FP4+ and HP5+ 120 rolls. My first development was with HP5+ rated at boxspeed (400 ISO) and @200 ISO. Developtime was 12:10 min. For the frames @400 ISO the density was to weak and the 200 ISO looked oke. But I didn't like the decrease of 1 stop speed and for as I known and read on APUG would Pyrocat-MC gives no speed decrease at all. I did a new trial and extend the dev.time to 15:00 min. This time it looks better but I'am not totally happy with it. Maybe a little bit longer in de dev. will overcome this.
My experience with FP4+ @ 125 ISO looks far better thats because I know that the recommended times must be far longer. I started with 12:30 min. Result the density is still to weak. Another run for 15:00 min. is a succes and I stick on it. You see that the recommended develop times are 200% of the published times by Photographer's Formulary. When I use this fact I have to develop HP5+ @ 18:00 min.
These developments take place in a Jobo CPP2 at "F" speed and @21°C (70°F) and 2500 serie drums.
For one film I mixed up 4:4:400.
I didn't trust myself at the moment to use only 250 ml working solution for one roll. Maybe later when everything is under control.
The use of the Stock Solution is very convenient and easy to mixe up the working solution.

 

[edtbjon]

Most films' real ISO are about 2/3 steps below the box speed with the recommended developers like e.g. D76/ID11, so your results at 200 ISO are probably correct. But it all depends upon how you take your readings, if your shutter(s) are calibrated etc. What ISO to use is a very personal thing and the development times etc. are normally starting points.
Another issue is whether you are using a normal negative, i.e. one developed in a non-tanning developer, as a norm. It is quite common for pyro-negs to look thin, as the image is built up by both the tan color and the silver. You have to enlarge (or measure with a color or UV densitometer) in order to really tell if the negs are too thin or not.
//Björn

 

[gainer]

It is hard to tell the printing density of a Pyrocat MC negative. The density and contrast will look much higher to the paper than to the eye, especially if you print on graded paper. On VC paper, try a test strip with high contrast filtration before you pitch the negative.