"polly filler" wrote in message
o.uk...
Hi All
Just bought some Agfa Viradon,, and on the instructions it
says to dilute1 to 50 for usage.
Then it says After toning wash thoroughly Na sulphite 10%,
prevents posttoning.
Could someone please explain the "Na sulphite10%" as I do
not understand.
Also what is the best way to use this toner to get the
best results? I have never used it before.

Many thanks in advance
Current Agfa Viradon is a polysulfide toner similar to
Kodak Brown Toner. Polysulfide has the odd property of
toning faster as it becomes diluted or exhauseted. That
makes it tend to tone quickly when washed until a
substantial amount of the toner is washed out. In addition
it can cause staining if not washed out quickly. Sodium
sulfite acts as a sort of stop bath, stopping the toning
immediately and also clears the yellow stain from the toner.
While its usually recommended that a 10% soluton be used I
find a working solution (about 2%) of Kodak Hypo Clearing
Agent works fine. Polysulfide also has the property of
toning all densities equally so it will provide considerable
protection to images when only partial toning is used.
Kodak published formula T-8 is a similar toner but not so
concentrated.



--
Richard Knoppow
Los Angeles
WB6KBL