Re: Papers

Date view Thread view Subject view Author view

From: Linas Kudzma (lkudzma@earthlink.net)
Date: 02/22/02-10:34:33 PM Z


Eric,
 I have not used any such ammonium based salts of platinum. Are you asking
about ammonium based Pt(II) salts, or an ammonium version of the Pt(IV)
salt? I belive that the higher oxidation state Pt(IV) in the so called
"NA2" from B&S is the reason for the contrast effect I was discussing. The
counterions, whether they be K+, Na+ or NH4+ may be mostly irrelevant to
the redox chemistry of the platinum. The way I see it, they should only
play an important role if they drasticly effect solubility of the salts.
I'm speculating here ....

Where do you get ammonium based Pt salts? I might want to give it a try.

Linas

> [Original Message]
> From: Eric Neilsen <e.neilsen@worldnet.att.net>
> To: <lkudzma@earthlink.net>
> Date: 1/16/2002 10:15:34 PM
> Subject: Re: Papers
>
> Linas, Have you tried using the ammonium based platinum salt or just the

> potassium based salt? I believe that you will see a rather large shift in

> contrast with it as well. I showed these results to Sullivan back in 1995

> in Santa Fe. I did not see, or remember a comparison to the ammonium
based

> salt in the paper you speak of. Did I miss something?

>

>

> Eric Neilsen

> Eric Neilsen Photography

> 4101 Commerce Street, Suite 9

> Dallas , TX 75226

> 214-827-8301

>

> Web Sites : www.ericneilsenphotography.com

> http://e.neilsen.home.att.net

> ----- Original Message -----

> From: "Linas Kudzma" <lkudzma@earthlink.net>

> To: "alt-photo-process-l" <alt-photo-process-l@sask.usask.ca>

> Sent: Wednesday, January 16, 2002 6:20 PM

> Subject: Re: Papers

>

>

> >

> > Witho,

> > I have not done extensive tests, but I have done some, and can say
with

> > absolute certainty that the so called NA2 platinum (Na2PtCl6) available

> > from B&S raises contrast considerably more that "normal" platinum. In a

> > test with 1:1 ratios of Pd/Pt, with each type of platinum, the so called

> > "NA2" complex gave a 3-4 step compresion of the scale when printing a

> > stouffer step tablet.

> >

> > The chemical explanation offered in the technical paper at the B&S site

> > makes perfect sense to me. It takes twice the amount of ferrous oxalate
to

> > reduce the Pt(IV) of the "NA2" complex to metalic platinum Pt(0). The

> > Pt(IV) complex uses up the available ferrous oxalate rapidly in areas of

> > lower exposure, and this compreses the scale.

> >

> > Linas

> >

> >

> > > [Original Message]

> > > From: Witho Worms en Jorien van Santen <verzet13@xs4all.nl>

> > > To: <lkudzma@earthlink.net>

> > > Date: 1/16/2002 2:52:22 AM

> > > Subject: Re: Papers

> > >

> > > I am curious if anyone has researched this contrasting agent except
for

> >

> > > Sullivan ? I was not able to detect significant changes in contrast
with

> >

> > > this product.

> >

> > > As far as I know and experienced the contrast is not more influenced

> than

> > by

> >

> > > adding just the 'normal' platinum solution to the palladium.

> >

> > >

> >

> > > Witho

> >

> > >

> >

> > >

> >

> > > ----- Original Message -----

> >

> > > From: "Linas Kudzma" <lkudzma@earthlink.net>

> >

> > > To: "alt-photo-process-l" <alt-photo-process-l@skyway.usask.ca>

> >

> > > Sent: Wednesday, January 16, 2002 4:13 AM

> >

> > > Subject: Re: Papers

> >

> > >

> >

> > >

> >

> > > > Wendy,

> >

> > > > What I was talking about was using what B&S calls NA2 platinum as
a

> >

> > > > contrast agent in place of B&S Sol#2. There is a good technical
paper

> >

> > > about

> >

> > > > this special platinum complex on the B&S web site.

> >

> > > >

> >

> > > > I'm surprised you can hang the sheets with B&S Sol#2 overnight. I

> found

> >

> > > > that anything with chlorate (as in sol#2) needed to be used promptly

> (a

> >

> > > few

> >

> > > > hours). It may be paper dependant? I don't use Platine.

> >

> > > >

> >

> > > > Linas

> >

> > > >

> >

> > > >

> >

> > > > > [Original Message]

> >

> > > > > From: Wendy Gollihue <wgolli@flash.net>

> >

> > > > > To: <lkudzma@earthlink.net>

> >

> > > > > Date: 1/15/2002 1:26:06 PM

> >

> > > > > Subject: Re: Papers

> >

> > > > >

> >

> > > > > Linas,

> >

> > > >

> >

> > > > >

> >

> > > >

> >

> > > > > I use the B&S palladium solution no. 3 that uses NaCl. I use the

> >

> > > Ferric

> >

> > > >

> >

> > > > > oxalates 1 $2 from B&S at 27%.

> >

> > > >

> >

> > > > >

> >

> > > >

> >

> > > > > Is your finding also true with palladium as the component. I
truly

> > have

> >

> > > > had

> >

> > > >

> >

> > > > > no problems hanging it (platine) all night in the dark but will

> listen

> >

> > > and

> >

> > > >

> >

> > > > > am willing to change to prevent upcoming difficulties that others

> have

> >

> > > >

> >

> > > > > experienced.

> >

> > > >

> >

> > > > >

> >

> > > >

> >

> > > > > Wendy (TX)

> >

> > > >

> >

> > > > >

> >

> > > >

> >

> > > > > ----- Original Message -----

> >

> > > >

> >

> > > > > From: "Linas Kudzma" <lkudzma@earthlink.net>

> >

> > > >

> >

> > > > > To: "alt-photo-process-l" <alt-photo-process-l@sask.usask.ca>

> >

> > > >

> >

> > > > > Sent: Monday, January 14, 2002 10:38 PM

> >

> > > >

> >

> > > > > Subject: Re: Papers

> >

> > > >

> >

> > > > >

> >

> > > >

> >

> > > > >

> >

> > > >

> >

> > > > > | Carl,

> >

> > > >

> >

> > > > > | Paper coated with only FeOx and metals, with the Pt component

> > being

> >

> > > >

> >

> > > > > | Na2PtCl6, can sit in the dark for days without any bad effect.
I'm

> >

> > > using

> >

> > > >

> >

> > > > > | Na2PtCl6 (sodium chloroplatiATE) as the contrast agent
(typically

> > 20%

> >

> > > of

> >

> > > >

> >

> > > > > | the metals). In fact, sometimes I like the prints better from

> such

> >

> > > > paper

> >

> > > >

> >

> > > > > | that sat in the dark overnight. Maybe this is due to a slower,

> more

> >

> > > even

> >

> > > >

> >

> > > > > | drying? This is for DOP prints on Cranes Cover 90 Natural.

> >

> > > >

> >

> > > > > |

> >

> > > >

> >

> > > > > | Previously, when I used chlorate for contrast, letting paper sit

> >

> > > > overnight

> >

> > > >

> >

> > > > > | was not possible. This was without a doubt due to side reactions

> of

> >

> > > the

> >

> > > >

> >

> > > > > | chlorate, which is a very reactive oxidizer. The Na2PtCl6 salt
is

> > very

> >

> > > >

> >

> > > > > | stable and a nice contrast agent.

> >

> > > >

> >

> > > > > |

> >

> > > >

> >

> > > > > | Linas

> >

> > > >

> >

> > > > > |

> >

> > > >

> >

> > > > > | > [Original Message]

> >

> > > >

> >

> > > > > | > From: Carl Weese <cweese@earthlink.net>

> >

> > > >

> >

> > > > > | > To: <alt-photo-process-l@sask.usask.ca>

> >

> > > >

> >

> > > > > | > Date: 1/14/2002 12:35:02 PM

> >

> > > >

> >

> > > > > | > Subject: Re: Papers

> >

> > > >

> >

> > > > > | >

> >

> > > >

> >

> > > > > | >

> >

> > > >

> >

> > > > > |

> >

> > > >

> >

> > > > > | > > Wendy: Internally sized. Very textured surface -- not good

> or

> >

> > > bad,

> >

> > > >

> >

> > > > > | just a

> >

> > > >

> >

> > > > > |

> >

> > > >

> >

> > > > > | > > question of whether you want that or not for a given image.

> >

> > > Tough,

> >

> > > >

> >

> > > > > | heavy

> >

> > > >

> >

> > > > > |

> >

> > > >

> >

> > > > > | > > paper. YOU HAVE TO "RE-ACIDIFY" IT for pt/pd printing,

> >

> > > >

> >

> > > > > |

> >

> > > >

> >

> > > > > | >

> >

> > > >

> >

> > > > > |

> >

> > > >

> >

> > > > > |

> >

> > > >

> >

> > > > > |

> >

> > > >

> >

> > > >

> >

> > > >

> >

> > > > Linas Kudzma

> >

> > > >

> >

> > > >

> >

> > > >

> >

> > > >

> >

> >

> >

> > Linas Kudzma

> >

> >

> >

> >

Linas Kudzma


Date view Thread view Subject view Author view

This archive was generated by hypermail 2b30 : 03/08/02-09:45:22 AM Z CST