A developer and a fixer question for RC paper

[Terrence Brennan]

Two questions for Those In The Know...

First, what (if any) chemical would be suitable as an additive to a standard B&W paper developer, such as Dektol or Bromophen, to make the D-Max higher on RC paper? Would an alkali like sodium carbonate work, and if so, how many grams per litre, for a start?

Second, I am looking for a rapid fix formula, for RC paper, for machine use. I need a formula for both a fixer and a replenisher. I have one formula, Kodak F-10, and F-10R, but they were designed for film, and F-10 does not appear to be a rapid fix.

Any information would be greatly appreciated!

 

[Mike Wilde]

To accelerate development, increase the alkalinity. The restrain development, lower alaklinity (by diluting the stock developer), or add a 'restrainer'.

Any developer can give a high DMax, on any paper if the paper is given sufficient exposire, and then nleft in the developer long enough.

Since you are hinting at the processing time with the fix machine use time, I suspect that you are having weak Dmax with short developer times that machine roller speed sets. Yes, more concentrated stock, used like Dektol 1:1 can help, as can adding measures of 10% soduim carbonate going only far enough until the whole print starts to develop, which leaves the mid tone and highlights looking muddy. Another way to get Dmax strong faster is to raise the temperature

'ordinary' developers used in a roller machine can oxidize easily, and thus 'poop out' early. There are commerical RT developers designed to combat this.

I have a roller transport, and when I load it with chems to process b&w I use home mixed Ansco 130 1:1. The glycin in the 130 is resistant to areial oxidation once in solution, but only works if warmer than the usual 20C. My machine with pumps running but no heaters on settles at 24C, which gets the glycin active enough that prints are good at RA speed of 45" per tank.

For fixing at 45" I fill my tank with DIY TF-3 at film strength of 1:3 (I think.. notes are not at hand.) I run developer in tank1 water in tank 2, and fix in tank 3. More washing happens in the wash/dry unit after the processor.

I have sucessfully run fibre prints through the machine as well. I prewet them with 30'" in a tray of water, then stick them face out to waste RC prints I keep for the purpose that are larger than the FB print. I pull the print sandwich apart after the processor, and do a hand fix2, and extended wash. RC carriers get soaked ina pail of water so that they don't carry too much fix in and kill of the developer with contamination when they are re-used.