Re: Pt./Pd. question acid pre-soak

From: Sandy King ^lt;sanking@clemson.edu>
Date: 08/09/05-12:19:50 PM Z
Message-id: <a06020408bf1ea420a1fe@[192.168.2.2]>

Mark,

You probably could have saved the potassium oxalate by adding back
oxalic acid to lower the pH.

Sandy

>Content-type: text/html; charset=UTF-8
>Content-language: en
>
>Kerik,
>
>I would agree. I tried some FAEW and used an oxalic acid presoak
>with it. I got good prints, but switched back to COT 320 because I
>did not like having to do the presoak. Once I began printing with
>the COT 320 again, I noticed I was not getting as good as results as
>before and determined that the Potassium Oxalate that I was using
>had somehow changed drasticly when using the FAEW. My guess was
>that it had gone very alkaline and PH tests supported this. I threw
>out that batch of Potassium Oxalate and mixed fresh developer and
>experienced no further problems.
>Mark Nelson
>Purchase the eBook & PDN System for Your Own Custom Digital Negative
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>
>In a message dated 8/9/05 11:39:29 AM, kerik@kerik.com writes:
>
>>I'm not interested in getting in a chemistry debate here. Note I said
>>*apparently* and perhaps I should have said alkaline rather than
>>*buffered*. But, I use a pH test pencil (Google it if you want to see one)
>>to check the pH of papers. I realize this is a rough estimate and there
>>are probably better and more precise ways to measure this, but FAEW shows
>>higher pH prior to acid treatment than most other papers I've tried.
Received on Tue Aug 9 12:20:03 2005

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