Ferri bleaching

Can a print be bleached in a dilute ferri to bring out the highlights if it has already been selenium toned?

Roger Pellegrini said:

Can a print be bleached in a dilute ferri to bring out the highlights if it has already been selenium toned?

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Yes. Selenium toner changes the image silver into silver selenide, a much more stable compound. Of course, this happens more in silver-rich shadows than in the silver-poor highlights. The toning actually protects the shadows from the bleach and makes highlight bleaching easier. However, people have reported tonal changes and staining, which I have not experienced.

Remember to thoroughly fix and wash after bleaching.

iirc, i did it once (following the advice of barry thornton: selenium-tone first, then bleach for more stable shadows) and an ugly brown color in the toned areas. this was with kentmere fineprint vc baryta paper.
(this was my experience and i never tried it again since. it's definitely possible that i made an error somewhere and that it will bleach fine with a better technique.)

Do the bleaching before the toning.

Ian

I use this stuff which is listed in Ansel Adams' book the print:
Solution A
Water (20°C)
(I use distilled water) 300ml
Potassium ferricyanide 62.5g
Potassium metabisulphite
(or potassium bisulphite) 4.2g
Water to make 500ml
Solution B
Water (20°C) 600ml
Ammonium thiocyanate 330g
Potassium bromide 30g
Water to make 1000ml



Adams also gives these instructions:

"Mix 1 part A, 2 parts B, and 10 to 15 parts of water.

Immerse dry print face up with vigorous agitation for 5 to 10 seconds, Place immediately in water and agitate until the bleaching solution has been removed from the surface of the print. Examine the print, and return if necessary to the bleaching bath (recommended only for a few seconds).

I actually use it these amounts to 30 parts of water and it is a brilliant method for brightening prints. The caution is that the procedure needs to be done as specified (quickly in and out of the tray and into rinse water)and the solution is good for one print, but it is very dilute. It should also be made fairly freshly due to poor keeping qualities. It is well worth doing...Evan Clarke

A points being missed, the OP has already Selenium toned the image, any bleaching back will leave a noticeable reddish brown tinge, the highlights must have already been to dark before toning, perhaps not noticed if the paper had a significant dry-down factor.

Ian

Roger

It looks like you just need to try it with your paper.

I don't often bleach but when I do either spot bleaching or the entire print I always mix the potassium ferricyanide with both water and some fixer and then refix, clear and wash. I've never had a problem with staining, only over aggressive bleaching. So I always make at least one extra print as a backup.