COBBLER'S PAGE

By Brian Asquith (Librarian)

Rapid Access (RA)

The club seems to be happy with the E6 formula although it does not always work as well for me with ELITE as with other makes, being rather harsh in rendering and taking a lot ofbleach/fixing. 

The formula for developing RA paper is under discussion now. I have used Ilford and Fuji paper with the formula I published some time ago in the CRC magazine which was taken up and circulated by Rayco. I assume it has been used with success by many, being so simple and using easy to get hold of chemicals. I have had no reason to change or experiment being quite happy with results. However, Bill has passed on comments made by Bill Broadhurst that he uses 5ml of Glycerine instead of 50ml  and it works but does not keep well. The Glycerine helps the flow and also improves the keeping properties. Although I do not consider keeping properties all that important as I mix immediately before use and use it till it is exhausted OR I have a stock solution of everything but CD4 mixed to double strength, so it is a quick job to mix 1-1 add CD4 and you're  away. I had an enquiry from a RAYCO customer about staining. 

He was getting a pink stain using this formula. I went through it with him but could not come up with the answer. He said he used the same paper with a kit and had had no problem so it must be the formula. I remember in the early days another member had a similar problem. I use dishes and do not get stain so I put it down to contamination in tank processing, but this does not answer the fact that with a kit it works OK. Now for further experiment. I have not tried the following method which was sent to me some time ago: 

TO MAKE 1/2 Litre RA DEV.
GLYCERINE                                                  25ml
HYDROX.SULPHATE                    10%sol    5ml
SOD.CARBONATE                      10%sol  150ml
CD4.STOCK SOL.CD4                               10gms
SOD.METABISULPHATE              10%sol/15ml
WATER                                                           50ml
CD4                                                               12.5ml
WATER                                                        500 ml 

Use at 35deg for 1min The sample print I received was superb. The remarks sent with the sample were:
"I USED THE SAME FORMULA IN THE DISH AND IT WORKED WELL. I HOPE IT MAKES YOU
HAPPY TO KNOW THE FORMULA WORKS WELL WHEN DILUTED AND TIMES EXTENDED
 BY THE WAY AGAINST ALL ADVICE I FREEZE THE SOLUTION AND IT THAWS OUT
WITHOUT ANY CRYSTALISATION. THIS METHOD EXTENDS THE LIFE CONSIDERABLY". 

I find the formula published in the last CRC magazine unnecessarily complicated by the use of % by weight formulation instead of equivalent in solid chemicals. Such high saturation of % solutions will surely lead to crystalisation of stock solutions. 

In answer to a letter in the 'DARKROOM TECHNIQUES' magazine for Nov/Dec 1993 the following was given; 

GENERIC RA 4 DEVELOPER
WATER                                                    800 ml
TRIETHANOLAMINE (TEA)                5-7 ml
CD.3                                                        5-6 gms
POT.SULPHITE                               0.5-1.5 gms
POT.CARBONATE                         3.4-4.5 gms
POT.CHLORIDE                             0.5-1.5 gms
ADD WATER TO BRING UP TO 1 LITRE.
PH 10.10-10.30 

It seems flexible but I have not used it yet! 

How do members find RA paper? I find that it does not seem to have the consistency of PE paper or is it that short development times lead to larger errors when temperature and time have small errors?

(Brian comments (page 5 on producing Sepia B&W slides, textured prints and the new Chrome Six Kit).