>
> >
> dots + white dots) can often appear on lith PAPER as well - this is said by
> some to be cured by adding some sodium sulphite to the dev... something to
> do with restraining the process without deactivating the dev.... but I find
> it a very erratic and difficult problem to predict. Sometimes it's there,
> sometimes it isn't. I wonder what theory people have for the black dot
> problem?
>
> By the way, I have found that different paper types are much more or less
> prone to these problems...
>
> Jonathan Anderson
>
>
Sodium sulphite is not a restrainer, if anything while being a
preservative, it is a accelerator. For example when Rodinal is mixed in a
5%solution of sodium sulphite instead of water, the development times are
almost cut in half. Litho developers are usually pretty concentrated and
very alkaline. I have noticed black specks arising from minute
undissolved particles of developing agent that sit on the paper and really
cook it. This may or may not be the case in your case. Are you using a
concentrated liquid developer, or mixing from powder?
John
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