From: Sandy King (sanking@clemson.edu)
Date: 12/08/02-02:19:22 PM Z
Liam,
I have been printing kallitype today and just out of curiosity tested
the theory that toning with gold, platinum and palladium in effect
"locks up" the image. I believe the results would pertain also to
VDB, though I am not absolutely positive. The actual VDB test would
be easy enough to conduct but I am currently in a "make print mode",
concentrating on kallitype and carbon and would like to avoid further
distraction.
In any event here is what I did.
My normal working procedure with kallitype is:
1. Expose
2. Develop
3. Two separate clearing baths, 3% citric acid, 2 minutes each
4. Tone
5. Two separate fixing baths
6. 1% sodium sulfite bath
7. Wash
When the two clearing baths are carried out one after another the
image will continue to bleach throughout the entire period. Toning
will then return much of the bleached image back and essentially lock
in the image for the remaining processing steps. That is, after
toning the image is essentially as it will look after processing is
complete, except for dry down.
For this print I did the following:
1. Expose
2. Develop
3. Clearing Bath #1, 3% citric acid
4. tone
5. Clearing Bath #2, 3% citric acid
Rest same ......
In this case the image was toned after Clearing Bath #1, meaning that
it had bleached much less than in the first case. It was then toned,
and after toning placed in Clearing Bath #2. However, there was no
further change in the image in Clearing Bath #2 after it had been
toned, and none thereafter. Dmax was considerably improved. So
clearly, in the case of kallitype the toner does appear to set the
image and prevent further fading of bleaching so I think logic makes
sense that it be done as soon as possible.
Sandy
>Sandy,
>
>Sorry, I do not tone very often and was thinking about the big "pop" when an
>untoned print hits the fixer. This, I think, might be lost. However, if
>this does not occur with toned prints, and *IF* it is something to do with
>iron (as it is with trad. Pt/Pd), then maybe toning "locks up" the iron in
>some way that could make clearing ineffective.
>
>
>
>Liam
>
>-----Original Message-----
>From: Sandy King [mailto:sanking@clemson.edu]
>Sent: 08 December 2002 18:45
>To: alt-photo-process-l@sask.usask.ca
>Subject: RE: VDB test results: related concerns
>
>
>
>Liam,
>
>I am not sure that the premise of your question is correct. When one
>tones a VDB print the image, whatever it is (silver, or gold,
>platinum or palladium plated silver?), is fully produced. Placing it
>in the hypo does not change the appearance in the least. This being
>the case, as I at least have observed, what advantage do you see in
>clearing after fixing?
>
>Sandy
>
>
>
>
>
>
>
>
>
>>Sandy,
>>
>>If image silver is produced by "solubilising" the iron with hypo, then
>>wouldn't the clearing stage would be better following the fix?
>>
>>
>>
>>Liam
>>
>>-----Original Message-----
>>From: Sandy King [mailto:sanking@clemson.edu]
>>Sent: 08 December 2002 17:32
>>To: alt-photo-process-l@sask.usask.ca
>>Subject: Re: VDB test results: related concerns
>>
>>
>>Ed Buffaloe wrote:
>>
>>
>>>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...
>>
>>
>>
>>I would expect some loss of density because acid bleaches the silver.
>>However, if the clearing baths are used after toning with gold,
>>platinum or palladium it is possible that there would be no fade back.
>>
>>What I would propose as an alternative VDB processing procedure for
>>maximum image permanence would be this:
>>
>>
>>1. Expose the print.
>>
>>2. Wash for a couple of minutes to get rid of most of the soluble
>>silver halides.
>>
>>2. Tone.
>>
>>3. Brief rinse.
>>
>>3. 2 minutes in clearing bath #1 = 3% citric acid.
>>
>>4. Brief rinse.
>>
>>4. 2 minutes in clearing bath #2 = 3% citric acid.
>>
>>5. Brief rinse.
>>
>>5. 2 minutes in fixing bath #1 = 5% sodium thiosulfate
> >
>>6. Brief rinse.
>>
>>6. 2 minutes in fixing bath ##2 = 5% sodium thiosulfate
>>
>>6. Brief rinse.
>>
>>7. 2 minutes in 1% sodium sulfite solution.
>>
>>8. Final wash of 30 minutes
>>
>>This is obviously a much more complicated procedure than what is
>>normally used for VDB but in theory it should establish the acidic
>>conditions that would assure maximum elimination of residual iron
>>salts. Is this necessary to get image permanence? I don't know.
>>Richard Knoppow has provided information on how to test for residual
>>silver salts. Does anyone know how to test for residual iron salts?
>>
>>
>>
>>Sandy King
>>
>>
>>
>>
>>>
>>>>
>>>> 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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