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View Full Version : Some Musings on Fixing and Toning



Paul Metcalf
9-Aug-2009, 21:08
First a confession - I got lazy tonight. (I feel better already.)

I've used rapid fixer for film and paper, both RC and fiber, and never really thought much about it (I know there should be a lot to think about, but I ignored most of it due to laziness. Is this a trend?). So tonight, rather than mix up my usual 10% solution of hypo for fixing saltprints, I mixed up a 1:9 solution of rapid fix (brand is not important I don't think). Wow, I was impressed with the reduction in the prints, almost rapidly. So I dumped that and went back to 10% solution of hypo, which works great and done in two baths (per Wynne White's process) but there is the smallest of reduction even with this.

But that got me thinking why don't I see any reduction in using rapid fix with commercial papers like Forte or even Azo. Azo is a silver chloride paper but so is a saltprint (sodium chloride + silver nitrate = silver cloride for the light sensitising agent). Is there something else in these papers that inhibits reduction from fixer?

Also tonight I toned some of the saltprints using a strong solution of rapid selenium toner, and there was quite a bit of reduction again (Wynne mentions this in his Vandyke tutorial due to ammonium thiocyanate in the rapid toner mix). But you don't here anyone talk about reduction in selenium toning commercial papers, usually the opposite is mentioned with an increase in Dmax (along with tone change and archival properties). So I ask again, what's in the commercial papers (esp silver chloride) that makes them act differently in terms of reduction to hand-coated papers?

Are any of the other alternative (aka hand coated sensitiser) processes subject to reduction in fixing and selenium toning?