Re: Uranotypes


Mike Ware
 

Bob -
In 1985 a 3rd year chemistry undergrad, Miss O. B. Wellesley-Cole, at Manchester did a project for me on "Uranyl carboxylates as photochemical imaging systems".
Her report has this tipped-in specimen, which was contact-printed from a 6x9 cm rollfilm negative of mine, one hour exposure to a small UVA lamp.
She possibly has made the first Uranochrysotype since C.J. Burnett in 1857!
You can see her sensitizer formulation: the molarities convert to 14% uranyl acetate + 10% sodium tetrachloroaurate, mixed 1:1. Very simple. It seemed pretty stable mixed.
The exposed print was stabilised in 5% sodium bisulphite solution, NaHSO3, to prevent highlight fogging, then washed in water. Easy to process.
Allow for colour inaccuracies in my scanning: I'd say the original was a claret or garnet red, 11D8/11E8 in the Methuen Handbook of Colour.
 


The title, BTW, is: "The Pike Pool, Beresford Dale, 1982."
A Derbyshire anglers' paradise!

Mike

P.S.Yes the acetate fluoresces more.
--
Mike Ware
https://www.mikeware.co.uk

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