Arches Platine paper is sucking back sensitizer in Winter (lower humidity.)

I have heard similar things about COT 320 being Platine that has been slightly altered. But it seems to have a different surface and feel, unlike Platine. According to Bostick and Sullivan COT is sized with Gum Arabic. I have only gotten one problematic batch in all the years that I've been using COT. That batch I gel sized and have been experimenting with it for carbon transfer. Works well, although my technique definitely needs some improvement. I also read somewhere, recently, that the Herschel paper from Ruscombe Mills was made using linen due to problems with available supplies of cotton. It's a real shame so few papers are compatible any more. Not counting Asian exotic papers, there are very few, maybe a half dozen papers that I know of that work for Pt/Pd printing. Pardon my dark thoughts.

Artonpaper, your dark thoughts are tending towards Dmax.

So then, if Platine has consistency issues, what are peoples thoughts and experience with other papers, (and let's just start with the one's easily ordered through Bostick and Sullivan or normally locally available at a big at supply shop in a large city).

Here is the list from Bostick and Sullivan:

Arches Platine
Bergger COT-320
Japanese Mullberry Papers (Kozo)
Lana Aquarelle
Revere Platinum
Rives BFK
Stonehenge

Please forgive the delay Doug.

Good advice on the papers. Lovely image by the way, with interesting geometry and feel. Pt/Pd suits it well.

One quick question: Does the paper shrink, and do you either pre-treat the paper so that shrinkage has already occurred before applying your first coat, or make two negs of slightly different size to deal with shrinkage. (Registration can be challenging if shrinkage occurs.)

Best holiday wishes,

Nick.

Hi Nick, No problem reply-wise, it is after all a time of year full of distractions.

Glad you like the image, it is my "test negative" for most things. I have carbon print scans of that among my APUG images.

I am only using a single exposure. I double coated the Stone henge in hope of getting a deeper D-max, which I think it did yield. So I coated, dried it, coated again, dried it again and then made a single exposure. I know Irving Penn used two different coatings, one low contrast one higher, and two separate exposures and developments. I understand he mounted the paper on aluminum sheets as some gum printers do to keep the paper size stable.. Seems like a lot places for things to go wrong.

Happy holidays to you too,

Doug

PS, I do not pre-treat. I have experimented with it and found no appreciable difference when using it with those two papers. I may experiment with BFK one of these days, just out of curiosity.

Here is a quote from an e-mail from Ron Reeder, regarding pre-treating paper.:

"mix up a solution of 1.5% oxalic acid plus 5 % glycerol (glycerin is the same thing). Brush this liberally on your paper, dry it, and then coat with the palladium solution. The oxalic acid keeps the surface of the paper acidic (which platinum/palladium likes) and the glycerol holds water. I use this method in the winter when I think my prints are getting a little gray in the blacks."

I wrote him originally because I was getting solarizing (lighter, bronzed looking shadows) when I switched work areas and switched over from a metal halide lamp to a fluorescent unit. But after cutting back on my base exposure I haven't had a recurrence of solarization and I've been skipping the pre-treatment with no ill effects.

Doug, that's interesting. I find I have to pre-treat Stonehenge, and I use only a single coat. Details here:
dennis spector - Platinum Workflow
I get really good blacks, and since I humidify my paper, I don't need to resort to glycerol. After some testing I found I can dilute the Pt/Pd emulsion with up to 20% water (the acidified Stonehenge turns into a sponge) with no loss of D-max. Also, I do mount on aluminum for gum-over-platinum prints and larger gum prints, so I think it's no problem if you're inclined to do multiple exposures. I'll be adding my how-to mount and register details on the website soon, I've got a cheap and easy bullet-proof system. All I need is some time to take a few photos and write it up.

Happy New Year!
Denny

Hi Denny, Thanks for sharing your Stonehenge info. I'll give it a try. I believe I still have some sheets.

I have never done gum over Pt/Pd, but I have done quite a bit of gum printing from camera negatives. Multi layer with varying amounts of color changes, some of that is on APUG, same screen name. Gum printing really is a wonderful medium.

I really liked your "Portraits in Stone." For some reason "Group Seven" really stood out for me. Maybe its the stone against the solid sky. great work.

Best, Doug

Thanks, Doug. If you get around to trying the acidified Stonehenge let me know how it goes.