Na2 method for Palladium printing

[Pete Suttner]

I'd like to try out this method having tried and experienced the short comings of the "ratio" method. Looking for smooth grain in the highlights and trying to avoid dichromate. My Internet searches yield only older threads and lots of conflicting information. Is there anyone out there currently printing Na2? What are your experiences with it? Any new discussion or experience would be appreciated!

Thanks - Pete

[Payral]

Have a look to Dick Arentz book Platinum and Palladium Printing
and there:
http://www.dickarentz.com/na2.html

I print mostly Platinum Palladium for more than 15 years and if I need/use contrat agent (not very often) I use Na2.
You can have a look to my prints to see results:
http://payral.pagesperso-orange.fr/selection_galeries2.html

[Pete Suttner]

I have Arentz book. He seems pretty fussy about measurement.

Enjoyed your work Philippe! Thanks

[peter schrager]

do a workshop with with tillman crane;it will save you time and money...he is doing one with the formulary very soon
Best, peter

[Eric Biggerstaff]

While I am not an expert, I use the Na2 method and get great results. I keep three different bottles with different solutions, one is 20% (full strength), a second at 10% and a third at 5%. This allows me to play with contrast a get the look I need. I find that I most often use the 10% solution. Also, I find that Na2 at 20% increases the exposure time.

Call up Bostick & Sullivan, they will give you great advice.

Eric

[Doug Howk]

You might also check B&S forum (http://bostick-sullivan.invisionzone.com/)
The only problem I had with the NA2 method is inclusion of platinum tended to cool the image tone, whereas I prefer a warmtone image. I therefore switched to the Dichro method as described in Ian Leak's workshop book.

[Pete Suttner]

I love warm tone look too. Ian Leake has a wonderful subtle touch. I have no fear of dark tone neutral.

[Cletus]

Peter - I've been pt/pd printing for a little over a year now and have only used "The Na2 Method" to this point. Early on I had a nice correspondence going with Carl Weese, a very accomplished platinum printer, and his advice got me off to a pretty good start. I also have D. Arentz, which is an essential reference IMO. Here are a few of the things I've begun to understand about using Na2 as a contrast agent - hopefully this isn't too "101" to be of any use -

I use pure Potassium Oxalate with a very small amount of Potassium Dichromate (10ml 10%\L of PotOx) and heated to ~30-40C as developer for all prints.

Start with pure Pd for the first print of every negative and use the result to determine the negative contrast and hence, whether and how much Na2 to add to subsequent prints. I sometimes make test strips with varying degrees of Na2, but I'm starting to question the efficacy of doing this. Metal salts are expensive!

Na2 is actually a restrainer and I believe it basically works by holding back the highlights and thus increasing contrast in the print. Also explains why exposure times tend to increase with more Na2 added. This may not be entirely accurate, but this is the way it appears to me.

I usually buy 10ml of 20% Na2 and then dilute with distilled water (using accurate pipettes) to end up with dilutions of 20, 10, 5 and 2.5%. Some people even go to 1.25-1.5% which might actually not be overkill. It's unusual for me to use it stronger than 10%. A few drops of 5 or 2.5% is usually sufficient for my negatives.

I expose HP5+ at ISO320 and process in Pyrocat HD 1:2:100 @ 22C for 15-18 minutes. This typically results in a very dense negative with print times between 12 and 15 minutes. I'm using an Edward's Engineered UV Box.

I once bought a densitometer to try my hand at pt/pd sensitometry ala Dick Arentz, but the densitometer I had wouldn't read pyro negs and I never really understood how to come up with a numerical value for negative contrast index or density range. Basically I've learned how to expose and process my negatives consistently and have been getting to the point where I don't think the numbers will really matter that much once you nail exposure and development.

I've never tried the other methods of pt/pd printing, so no good frame of reference there. I think it's safe to say that the goal is to use as little Na2 as possible and then only to 'compensate' for the negative CI. This means a little Na2 goes a long way but you will use a lot of palladium.

I've gone on a good long time now and I'm not sure whether I've imparted anything of value from my little experience with Na2 pt/pd printing. Maybe if there were a specific question I might could answer?

[Jim Noel]

I have been printing Pt/Pd for over 20 years. Early on I decided the ratio method had its' limitations. I use as little dichromate in my dark room as possible so looked for another oxidizer and settled on Hydrogen Peroxide which is now recommended by more than a few people. I add it directly to the sensitizer before coating. A little goes a very long way so I generally use one, or at the most two, drops of 1.5% for an 8x10.
I have not used NA2 because of its cost.

[Vaughn]

I have used Na2 a little bit. I have looked at Na2 as more of an accelator than a restrainer...building up blacks faster. But I suppose it does not matter as long as it works!

I prefer to use no contrast agent at all, and 99% of the time do not. Instead, I expose and develop my negs to the desired contrast. I got into that habit when I was teaching myself carbon printing and applied it to platinum/palladium printing. What is nice is that if a neg has too much contrast for pt/pd, it will have a great contrast range for carbon printing! I have used Na2 primarily for printing MF negatives that I have not processed the negs specifically for alt processes.

I use pt/pd at a ratio of about 1 part pt to 3 parts pd. I develop in warm Potassium oxalate, which gives me a rich warmth to the prints, yet nice solid blacks.

[Pete Suttner]

Cletus, Jim, Vaughn, thanks for the input. It's all helpful to pick through some of the many variables. I'm sure there are other folks out there asking some of the same questions.

I've been printing / experimenting with 5% solution per Bostic and Sullivan's drop count recommendations. Gone is the graininess. A drop or two on 8x10 print seems to give the pop that I was looking for. Also been heating Potassium oxalate developer for a warm tone so my inexperienced panic about Na2 being stone cold neutral has been relieved.