From: Ed Buffaloe (EdBuffaloe@UnblinkingEye.Com)
Date: 12/08/02-04:30:20 AM Z
3% citric acid might be too strong for VDB. After 2 minutes each in 6
successive trays of water with only a pinch of citric acid, I find that my
VDB has become visibly less dense. Of course, it seems to gain much of it
back in the fix...
>
> This is an interesting observation, and one that could explain why
> with similar processing my VDB prints fog when exposed to strong UV
> light, while kallitypes do not. The primary difference in my
> processing procedures is that the kallitypes go through two separate
> clearing baths of 3% citric acid, a step that is omitted in
> processing VDB. If this difference alone explains the fog then it
> would appear to result from residual ferric oxalate, not residual
> silver salts.
>
> Two questions. First, I wonder what would happen if one followed Ed's
> clearing procedure but carried it out in the conditions I described,
> afternoon shade where there would be still a lot of UV light. Second,
> has anyone tried to process VDB using Kallitype clearing procedures?
> I suspect that the use of a citric acid clearing bath before fixing
> would bleach the image quite a bit, but perhaps if the clearing was
> used after toning there would be no bleaching?
>
> Sandy
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