[Alt-photo] Re: DAS

[Loris Medici]

Wow, great info. Thanks very much! Doesn't sound too difficult; are
those clearing solutions harmless in terms of longevity in some way?

BTW, what can you say about 6% sensitizer per gram of gelatin? My aim
is to pour a thick but lightly pigmented tissue for high relief...

Regards,
Loris.


2013/4/17 Kees Brandenburg <workshops at polychrome.nl>:
> I have to test this more systematicly, but this is what I have found now.
>
> Single transfer carbon transfered on:
>
> - RC fixed out photopaper - little or no stain
> - Fixed out baryta paper - some stain also in the parts were the tissue was covered by the negatives safe edge.
> - Gelatin coated, glutaraldehyde hardened water color paper: very visible stain, difficult to clear.
>
> Double transfer carbon on (albumen cioated) polyester or polycarbonate
>
> - no visible stain, maybe spectral measuring should reveal some I think
>
> DAS caseïn on:
>
> - gelatin/glutaraldehyde sized watercolor paper - some stain bulding up at consecutive layers
> - PVA sized paper - I have the impression staining is less on these but I have to test more to be sure
>
> Clearing
> =======
>
> The ultrastable clearing bath recipe is:
>
> Stock Clearing Bath A:
> Water (at 110 F) 930 ml
> Potassium Permanganate 6 g
> Sodium Chloride (Table Salt) 14 g
>
> Stock Clearing Bath B:
> Water (at 110 F) 940 ml
> Sodium (Meta)Bisulfite 30 g
> Sodium Sulfite 30 g
>
> To make working solutions of A and B, dilute each in cold water at 1:20. Prints are immersed in Clearing Bath A for
> 1 minute, followed by a brief cold water rinse and then placed in Clearing Bath B for an additional minute. After a final rinse, the
> print is dried and ready for finishing.
> Quote from Charles Berger in this thread: http://www.apug.org/forums/viewpost.php?p=1182350
>
> Kees
>
>
>
>
>
> On 17 apr. 2013, at 08:46, Loris Medici <mail at loris.medici.name> wrote:
>
>> Kees, can you tell us a little more about the stain? I plan to use
>> (thin but strong) Masa paper as tissue support and want to do single
>> transfer. Will I have to use permanganate for clearing? If yes, what's
>> the down side of this procedure?
>>
>> Regards,
>> Loris.