Processing time/temp in pyro for platinum negs

[Natha Congdon]

Just got back from a WONDERFUL photo trip to Angkor Wat w/ my 8 x 10 and have 70 + sheets of Tri-X, HP5+, and Bergger film that I hope to process in Pyro for pla tinum printing. I've been using Pyro for negs for silver printing up until now, but am hoping to get started in platinum now (hence the experimenting with thre e different films, as I gather Tri-X has advantages over my usual HP5+ for Pt/Pd ). I have more than one copy of many of the best shots, so I'm able to do a lit tle experimenting without risking once in a lifetime shots. Any suggestions for first approximation concentrations and developing times/temps for any of these films in Pyro to produce negs for Pt/Pd printing? The times suggested in the We ese/Sullivan book mostly relate to Rollo/Pyro, and those they suggest for Tri-X for tray processing (which is what I use) don't seem that different from what Hu tchings suggests for negs for silver printing. I would expect the times to be c a. 50% longer.

Also, any personal experience with using the same neg for silver and Pt/Pd when processed in Pyro? This is a claim I have often heard made, and would love it if it were true.

Thanks in advance for any suggestions. Feel free to email if you have any quest ions about Angkor Wat, LF in Cambodia, etc. Truly one of the world's most amazi ng sights!

Thanks,

Nathan

[Brian Ellis]

"Photo Techniques" magazine recently published an article on using pyro to make negatives for both silver and platinum printing. I believe it was two or three issues ago (i.e. mid or late 2000). It should be easy enough to obtain a copy of the issue in which the article appeared since it was so recent.

[Michael_527]

Nathan,

I haven't tried pyro yet, but Carl Weese wrote an article for Photo Techniques (NOV/DEC 1999) that was quite good. He is actively involved in the alt-photo discussion forum, and would probably be a good person to talk to about this specific subject.

The article discussed printing a pyro negative on both silver and Pt/Pd, and had starting times for development.

Here's a brief amount of info from the article:

Tri-X (working speed 160-200) PMK pyro for 10-12 minutes at 75 degrees.

BPF 200 (effective speed 64) PMK not recommended, too strong of base stain, recommends ABC+ rotary.

HP5+ (working speed approx 250) PMK pyro 20 minutes or longer, may require a stronger than normal dilution of developer.

You may want to join into the discussions on the alt-photo board and look at the archives, because there's a wealth of information about platinum printing, and film, and developer, and... and... and...

Go to:

http://members.nbci.com/_XMCM/altphotoprc/index.html

for more info. There's a link on there on 'how to sign up', and all the archives are listed. There's also a searchable list at:

http://www.listquest.com/lq/search.html?ln=altphotoprocess

you can do a search for 'pyro' or whatever, and probably find some real useful info.

One last thing, I think Carl tends to print a little flatter than I would like, so he may be using a bit less time than I would use. He is also printing using Ziatype, which, as a print-out process, is selfmasking, which can affect the results.

One of these days, I'll get down to DC for an evening of photography.. . maybe in April, I'll email you to see if you want to join in the fun. Maybe by then you'll have the 12x20, (not likely, I know).

---Michael

[David Richhart]

There is an interesting online article on the technique of platinum/palladium printing at www.onlinephotography.com/plat.html

It sounds like you may be more experienced in the process and the article might be a bit too simple to help you, Nathan, but I am sure there are many on this forum that will find it interesting...-Dave

[Michael_527]

Nathan,

I just came across the entire article I had mentioned above. It's at the Photo Techniques website at:

http://www.phototechmag.com/previous-articles/nov99-weese/nov99-weese. htm

So, you can read it for yourself...

---Michael

[Carl Weese]

Most recent development (yesterday) was some 7x17 HP5+ done in PMK in trays for 16 min at 72 degrees, and some TXT for 12 min at 70 degrees. The TXT looks perfect for Pt/Pd but will also print beautifully on VC silver papers, or a soft graded silver paper. The HP5+ could have used 20 minutes (or a higher temp) but will again be perfect for VC silver and just fine for develop-out Pt/Pd. Probably a bit soft for POP without contrasting agent.

Crossover negatives from pyro are indeed real. "Normal" pyro negs intended for silver aren't bad for Pt/Pd, but some extra development helps the platinum prints and doesn't hurt the silver as long as you use variable contrast papers (which have a favorable response to the color of the pyro stain, lowering the contrast). That same stain color is what raises the effective contrast for Pt/Pd or other UV-sensitive processes. What I wrote in PT in fall of 1999 remains valid, though I'll add that in addition to Agfa Multicontrast Classic, I now find that Kodak Polymax Fine Art (fiber) and Ilford Multigrade Warmtone (fiber) also do well. Note that VC filters don't work in quite the same way with pyro negs as with plain silver negs so experimentation will be needed when using filters or colorhead settings to adjust printing contrast of pyro negs. The different papers have quite different responses as well. Happy expe