Anyone have experience using Na2 Pt/Pd and regular Pt/Pd ?

I understand the Na2 is used mostly as a contrast boost, and it can be a significant increase. If I'm looking for contrast change, is it easier to control that by just adding a drop or two of Pt vs using Na2 ?

I'm working with in camera negatives if that matters (5x7 up to 7x17)


tia
freddy

Yes, in an Na2-based process it is used to increase contrast. If you buy pre-mixed, it typically comes in either a 5% or 20% solution. And, yes, it's powerful stuff so you need to be careful. I don't use it much anymore, but back when I did I had several dilutions available to me down to 2.5%. Just don't mix Na2 with any mix that includes platinum. If you want to go with straight palladium or a pt/pd mix, potassium dichromate can be used to increase contrast. Also, you might research a bit on the ABC method.

thanks Alan ! I may get the Na2 kit cuz Bostick and Sullivan can't ship Potassium Dichromate up here. Cld try and find it locally but might be easier to get the Na2 and adjust the dilution.

For about a year now, I've been successfully using the formulas found here: http://texaschrysotype.com/pdfs/21stCenturyAlchemy.pdf
I have found they are easy to adjust for contrast, and the fact that they print-out take much of the guesswork out of it. No need for test strips or any of that, just check it as it's printing out and stop when it looks good. Development is just a matter of washing out the iron. Overall contrast is similar to develop-out platinum, so a negative suitable for that works well with this.
If you're interested in trying it, I'm more than happy to give advice.

Fred - Ian Leake wrote an excellent article on Pt Pd printing, you are welcome to drop by and borrow my copy to see if it fits your needs, If I did not go down the digital negative route I would have used his method of having different contrast developers, makes a ton of sense to me.

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Originally Posted by martiansea

For about a year now, I've been successfully using the formulas found here: http://texaschrysotype.com/pdfs/21stCenturyAlchemy.pdf
I have found they are easy to adjust for contrast, and the fact that they print-out take much of the guesswork out of it. No need for test strips or any of that, just check it as it's printing out and stop when it looks good. Development is just a matter of washing out the iron. Overall contrast is similar to develop-out platinum, so a negative suitable for that works well with this.
If you're interested in trying it, I'm more than happy to give advice.

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thanks ! more reading material :)

Quote:

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Originally Posted by bob carnie

Fred - Ian Leake wrote an excellent article on Pt Pd printing, you are welcome to drop by and borrow my copy to see if it fits your needs, If I did not go down the digital negative route I would have used his method of having different contrast developers, makes a ton of sense to me.

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thanks Bob. I really should sit down with Dick Arentz's book since it's in my pile of *have to reads* haha

While I want to stick to in camera negatives, I do see a time when I might have an image that I want larger than say 2 1/4x 2 1/4 and will need to go digital.

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Originally Posted by Fred L

While I want to stick to in camera negatives, I do see a time when I might have an image that I want larger than say 2 1/4x 2 1/4 and will need to go digital.

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Not necessarily...you could enlarge a small negative on to Ortho Lith film (creating a positive), then contact print that for a negative to be printed conventionally.