chemical quantity question

[nlochner]

Hello, i just bought a "colour by beseler" RA-4 11x14 printing drum, and i was wondering how much chemical i should put in it every time. My 8x10 drums require roughly 1.5 oz chemical.


Thanks very much

nlochner

 

[donbga]

Hello, i just bought a "colour by beseler" RA-4 11x14 printing drum, and i was wondering how much chemical i should put in it every time. My 8x10 drums require roughly 1.5 oz chemical.


Thanks very much

nlochner

3 ozs.

 

[nlochner]

I just printed a photograph, and it's perfect, so 3 oz. worked well.

Thanks, alot

nlochner

 

[Mike Wilde]

Not all chemicals are treated equally in RA-4

Your question pertains to how much to put in the tank.

There is also the issue of how much chemistry the print actually consumes.

If you buy your chemistry in a kit it may not matter, but if the individual dev, stop , and blix are bought separately then there is the opportunity for economies.

Use 3 oz developer, fresh every time.

Use fresh stop every time . You may be able to make your own stop from
diluting conventional B&W stop bath stock solution. I make mine using 10ml of 80%+ glacial acetic acid per litre.

Use 3 oz of fresh blix for the first print. Save it in a jug. For the second print add 2 oz of fresh blix, and the balance of re-used blix.

The major cost of the process is the ferric ammonium EDTA in the blix, and it is not all consumed, but the 80ml is needed to wet the print.