Is it possible to achieve paper-white when using pt/pd bostick & sullivan na2 formula

[bredd]

Also using Dan Burkholders ​Negative Companion 2013.

 

[Vaughn]

Hello. First, just in case -- one does not use the regular platinum salts when using Na2...one should use Na2 with just palladium. Something to do with the regular platinum salt and the Na2 cancelling each other out. It certainly was the case when I did it...I kept raising the number of drops of Na2 without seeing much of a contrast change.

And yes, I have achieved paper white with Palladium/Na2. I was using camera negatives (120 film and sheet film), tho...not inkjet negs.

 

[Ian Leake]

Yes. Although, as Vaughn said, Na2 only works for palladium.

There are three common reasons for not getting paper white:
1. Over-exposure
2. Insufficient clearing
3. Fogging

The first is easy to test - just reduce your exposure time and see what happens. Negatives of any type can be too thin for Pt/Pd. High quality inkjet negatives can be quite difficult to make for pure Pd prints because of the high Dmax needed.

Some papers can be hard to clear with straight EDTA. If you have a slight tone in your highlights then try extending your clearing time and/or, if you're using EDTA, add some sodium sulphite.

It is quite easy to fog your paper during coating and drying. You should work under the dimmest light you can. If you leave paper to dry in any light then it can fog slightly and give you tone in your highlights. A very slight warmth in the highlights can often be very attractive, so it may be more sometimes be good to accept a little fogging and aim for a 'convincing white' rather than a 'paper white' (so long as this isn't caused by poor clearing).

 

[Vaughn]

I use EDTA and Kodak Hypo Clearing Agent - which is basically Sodium sulphite (~75%), Sodium metabisulphite(~15%) and the remainder (in about equal amounts) citric acid and, ta da, EDTA. Depending on what continent you live on, the HCA is easy to use...there are other brands out there. But I might just start buying the Sodium sulphite bulk as Ian mentioned -- but Kodak HCA seems to be one of the cheapest washing aids out there.

A step wedge is a handy little thing if you have one. DPUG (digital photo companion to APUG) would be the place to discuss creating digital negatives (and step wedges) and fine-tuning such for various alt processes.

 

[pschwart]

Some papers can be hard to clear with straight EDTA.

I have actually never been able to completely clear any paper using just EDTA or citric acid. My first bath is citric acid, my second bath is EDTA + sodium sulfite, and I often use a third bath of HCA or something equivalent. Sounds pretty much like Vaughn's workflow, and it works for me.

 

[bredd]

I would like to thank you all for the replies to my query.