Temperature coefficient of Phenidone?

[neelin]

Can anyone lookup/tell me the TC of Phenidone alone? I haven't been able to locate a resource that includes that number. I've been using it in a simple sulfite/carbonate developer & getting out of the heating season in the Great White North, the apartment temperature will be fairly variable.

Thanks.

 

[Alan Johnson]

What developer contains only phenidone,sulfite and carbonate?
As you may know,as a rough guide the rate of development doubles for every 10 degrees C increase in temperature.
In the case of phenidone sulfite (POTA) the relevant data, if it was measured, may have been filed away by the inventors,that would be about 1967.

 

[neelin]

What developer contains only phenidone,sulfite and carbonate?
As you may know,as a rough guide the rate of development doubles for every 10 degrees C increase in temperature.
In the case of phenidone sulfite (POTA) the relevant data, if it was measured, may have been filed away by the inventors,that would be about 1967.

ahhh...that would be my RW1 pretty much Crawley's FX-1 with 1/10 Phenidone instead of Metol.

I tried POTA (P/Sulfite) & Delagi#8 (P/Sulfite/Borax) on my Agfa Scopix 35mm X-ray film. It's an ortho "T-grain style" emulsion with extremely high contrast. I shoot it at EI 80. Delagi#8 was not bad, but the carbonate gives me the most attractive contrast/grain combination from my experimental results. My starting pH is somewhere over 9.5 (where my test paper gives up).

I'll probably use Metol's TC of 1.3 for starters. From Basic Photographic Materials and Processes, Stroebel, Current, Zakia. They had also listed 1.9 for both Pyrogallol & MQ formulations & 2.5 for Q only formulations. IIRC Mees & James had listed p-aminophenol at 2.6.

I'll take a quick peek at D-23 (Metol/Sulfite) to see if it is anywhere near 1.3 on any published charts they may have.