AHA!!! WAS Trivia time: room temperature solubility of platinic acid

DEAR LIST,
        Finally an answer to the question I asked last year!!! I asked the
list if I could use Na2 as a contrast control agent when using a mix of
PT/PD in DOP prints. I mentioned that I used about 4 Pd to 1 Pt ratio. I
don't recall getting a definitive answer but the gist was that it should
work and that I should try it. Below Clay states that if there is any Pt in
the mix it won't work. Sooooooooooooo... CHEERS! BOB

 Please check my website: http://www.bobkiss.com/

-----Original Message-----
From: Clay [mailto:wcharmon@wt.net]
Sent: Friday, December 09, 2005 10:12 AM
To: alt-photo-process-l@sask.usask.ca
Subject: Re: Trivia time: room temperature solubility of platinic acid

The problem is that using Na2 as a contrast agent only works with
pure palladium prints. Any platinum in the mix and the Na2 reverts
from the +4 oxidation state to the +2 oxidation state.

Yes, it will still cool the tone in a lithium palladium print.

On Dec 9, 2005, at 7:57 AM, Eric Neilsen wrote:

> Maybe in my brevity I should have included a platinum (oops
> palladium) terms
> like the recent Gum thread. When I used Na, it meant Sodium the
> element;
> when I used Na2 that was in reference to the contrast agent. Those
> would
> have two different impacts on a print.
>
> Na2 can also be part of the chemical expression for the palladium
> salt,
> Na2[PdCl4]. That is not how Na2 was being used here.
>
> Clay, have you see your mixed prints, platinum and palladium,
> showing the
> same quick cool down? Or only those where the only metal salt was
> Na2[PdcCl4]? And have any of you, seen a significant cooling of a
> print made
> with NH4 as your base for the palladium solution? Or for lithium?
>
>
> I agree with everyone about Na2 - it takes only a small
>> amount to
>> significantly cool down a palladium print, ceteris paribus
>
> I haven't seen it with my ammonium palladium prints. It may be that
> with all
> palladium prints made with sodium based palladium only, that ceteris
> paribus, applies. I would also add that before one can start
> attributing
> too many characteristics to a particular part of a palladium print,
> all
> components need to be listed and accounted for. The ferric oxalate
> will play
> a roll in the color of your print. The full interaction of all the
> components have not been tested by me recently, but about 6 years ago,
> sutble differences in color could be achieved by using a ferric
> oxalate from
> B&S, The Formulary, Artcraft or my homemade brew.
>
> The color shift may in part be due to interactions not based on
> sodium but
> pH changes. We all wait your test.
>
>
> Eric Neilsen Photography
> 4101 Commerce Street, Suite 9
> Dallas, TX 75226
> 214-827-8301
> http://ericneilsenphotography.com
>> -----Original Message-----
>> From: Clay [mailto:wcharmon@wt.net]
>> Sent: Friday, December 09, 2005 5:33 AM
>> To: alt-photo-process-l@sask.usask.ca
>> Subject: Re: Trivia time: room temperature solubility of
>> platinic acid
>>
>> I'll let you know. The stuff is still in a small plastic bag in
>> the
>> form of crystals. So experimentation is forthcoming.
>>
>> I agree with everyone about Na2 - it takes only a small
>> amount to
>> significantly cool down a palladium print, ceteris paribus.
>>
>> Clay
>> On Dec 8, 2005, at 11:46 PM, Eric Neilsen wrote:
>>
>>> Well, Yes. Perhaps my point missed both you and Sandy. Does
>> the Na2
>>> produce
>>> prints of warmer color than prints made using Platinic Acid,
>> where
>>> the Na is
>>> replaced in the compound by H. Discounting the effect that PT
>> would
>>> have on
>>> the image tone by cooling it down a bit, and since the same
>> amount of
>>> platinum is in both the magical Na2 and in Platinic Acid,
>> what then
>>> accounts
>>> for any difference in image color?
>>>
>>> So Clay, have you used both? What say ye?
>>>
>>> Eric Neilsen Photography
>>> 4101 Commerce Street
>>> Suite 9
>>> Dallas, TX 75226
>>> http://e.neilsen.home.att.net
>>> http://ericneilsenphotography.com
>>>
>>>> -----Original Message-----
>>>> From: Kerik [mailto:kerik@kerik.com]
>>>> Sent: Thursday, December 08, 2005 5:52 PM
>>>> To: alt-photo-process-l@sask.usask.ca
>>>> Subject: Re: Trivia time: room temperature solubility of
>> platinic
>>>> acid
>>>>
>>>> On Thu, 08 Dec 2005 17:18:43 -0600, Eric Neilsen
>>>> <e.neilsen@worldnet.att.net> wrote:
>>>>
>>>>> In fact I can see no reason why it wouldn't
>>>>> work as well or better than Na2. Better? More neutral. Na
>> has a
>>>>> tendency
>>>>> to warm up palladium prints, so I'd expect the elimination
>> of it to
>>>>> reduce the warmth of your print.
>>>>
>>>> Hmmm... no. Na2 causes Pd prints to shift towards neutral.
>>>>
>>>> Kerik Kouklis
>>>> www.kerik.com
>>>
>
Received on Fri Dec 9 08:35:44 2005