RE: Oxalic Acid for Pt./Pd.

Don, I believe the Rudiak/Kennedy work was done shortly after I had ask
Sullivan to discuss the FO powder that he was selling, it's Sp Gr and
relative printing speed. It may have been in the works but this was quite a
number of years back.

Rudiak's developer that we used while our partnership business was active in
Taos, included some oxalic acid as well as Sodium Phosphate Di Basic.
John's formula work fine, except that is was slower and tended to give
grainy prints when it was remotely tired. Fresh batches were always better
than seasoned work. I usually used standard Pot Ox with extra Ox Acid.

Eric Neilsen Photography
4101 Commerce Street
Suite 9
Dallas, TX 75226
http://e.neilsen.home.att.net
http://ericneilsenphotography.com
 

> -----Original Message-----
> From: Don Bryant [mailto:dstevenbryant@mindspring.com]
> Sent: Wednesday, September 15, 2004 11:22 AM
> To: alt-photo-process-l@sask.usask.ca
> Subject: RE: Oxalic Acid for Pt./Pd.
>
> Sandy,
>
> Yes adding oxalic acid to the FO solution has been suggested most notably
> by
> David Kennedy and the late John Rudiak. If you have a copy of "The New
> Platinum Print" refer to the 'Notes from the field' section on page 78.
> According to that section an increase in speed should be expected with the
> addition of oxalic acid to the FO solution but there is no mention of
> increased DMAX.
>
> Also if you check Rudiak's web page he lists a developer formula that uses
> oxalic acid as an ingredient.
>
> I may be wrong about this but I believe I've read somewhere about printers
> who have brushed on or first coated the paper with a solution of oxalic
> acid
> before coating with the standard palladium solution.
>
> I've not tried any of these methods.
>
> Don
>
> > -----Original Message-----
> > From: Sandy King [mailto:sanking@clemson.edu]
> > Sent: Wednesday, September 15, 2004 12:02 PM
> > To: alt-photo-process-l@sask.usask.ca
> > Subject: Oxalic Acid for Pt./Pd.
> >
> > I get higher Dmax by about 0.10 - 0.20 with most papers in Pt/Pd.
> > printing by first soaking in a 1% solution of oxalic acid, then
> > drying without rinsing.
> >
> > Soaking papers this way is not terribly inconvenient, but I am
> > wondering if anyone has experimented with adding oxalic acid directly
> > to the sensitizer before coating?
> >
> > Sandy King
> >
> >
>
Received on Wed Sep 15 18:01:40 2004