Anginapectoris
Hello,
Does anyone know whether the colour developing agent for the RA-4 colour process (positive processing) can be made at home cheaply and without too much effort? There are plenty of guides online for making your own photographic chemicals, but none for the colour developing agent.
Kind regards,
Bypass
Wolfgg
Hello,
Try this:
800ml water
4ml Fotoplex 1
0.5ml Fotoplex 2
30g potassium carbonate
0.2g anhydrous sodium sulphite
4ml diethylhydroxylamine
10ml triethanolamine
2g table salt
0.01g potassium bromide
5g CD3
Top up with water to 1000ml
Development time at 20°C: up to 2 minutes.
Best regards, Wolfgang
Wolfgg
Here is another RA4 formula using CD4:
800ml water at 20°C
5ml Fotoplex 1
0.5ml Fotoplex 2
6ml diethylhydroxylamine
100g potassium carbonate
10ml triethanolamine
3g table salt
6g CD4
Top up to 1000ml
Development time approx. 1 min at 20°C
Regards, Wolfgang
Anginapectoris
Hello,
Try this:
800ml water
4ml Fotoplex 1
0.5ml Fotoplex 2
30g potassium carbonate
0.2g sodium sulphite (dry)
4ml diethylhydroxylamine
10ml triethanolamine
2g table salt
0.01g potassium bromide
5g CD3
Water to make up 1000ml
Development time at 20°C: up to 2 minutes.
Regards, Wolfgang
Hello,
thanks for the quick reply. The preparation seems straightforward enough. But where do I get hold of the ingredients? I haven’t the faintest idea.
Kind regards
Bypass
CPD
Hello Bypass,
There is a collection of recipes by a Mr Raffay, which also includes a few recipes for colour bears. The book – which is actually a bound set of photocopies – is (or was?) available from Brenner at a high price. This supplier also stocks a selection of photochemicals, though they aren’t exactly cheap.
The recipe collection is riddled with errors in places, and the author admits that he has never tried out many of the recipes himself. It would have been nice if he’d added which ones he has experience with and which ones he doesn’t. In many areas, the recipe collection simply seems to me to have been copied and pasted, and is full of spelling mistakes and incorrect translations. For instance, he consistently spells the American photographer Weston as “Westen” and translates the term “edge effect” as “Eckeneffekt”. For the price, I’d expect a bit more care. But if you’re set on it, I’d be happy to share a few of the recipes with you sometime soon.
But – do you really want to put yourself through that? As for the colour toners, it might be justifiable to make your own with black-and-white toners, but I don’t think it’ll work out any cheaper, not to mention the consistency of your toners.
Regards, CP
Wolfgg
I have used the above formula with CD4 successfully for years.
Here is some additional information:
http://www.bonavolta.ch/hobby/en/photo/c41_ra4_chemicals.htm
or Kodak patents:
http://www.patentstorm.us/patents/5578431-description.html
Best regards, Wolfgang
Wolfgg
I've just happened to come across someone else here who also does their own hair colouring:
http://www.fotolaborinfo.de/fotolabor/fselans.htm
Best regards, Wolfgang
Wolfgg
And if you want to build the scales yourself, here’s the link:
http://www.geocities.com/ResearchTriangle/...693/waage2.html
Best regards, Wolfgang
ravebenni
Can I use black-and-white fixer to remove the silver from RA4 paper?
I have a roll of 158m × 10cm laminated RA4 paper here. From what I’ve read, I shouldn’t expect any usable results from it anymore. Now I’m wondering if I can at least recover the silver. As I have black-and-white fixer to hand, it would be great if that were possible. The fixer would then need to be de-silvered afterwards.
Apart from the effort involved: does the SW fixer extract the silver from Ra4 paper?
cfb_de
Hello Benjamin,
Yes, that’s possible. However, the cost of the fixer, the subsequent desilvering and cleaning of the silver is considerably higher than the value of the silver itself.
You’d also need to fix the paper in the dark. How would you go about that in practice? After all, it’s nearly 16m².
Best regards,
Franz
ravebenni
Thanks for your reply.
I don’t understand, though, why I’d have to do this in the dark. When I test my silver-based fixer using a piece of undeveloped film, it does turn clear. A tiny, invisible amount of silver remains, caused by the light leak – the latent image, so to speak.
Please correct me if I’m wrong.
I realise I can’t make a profit from this. I’m thinking more about the environment. If the chemicals I take to the collection point end up as incineration ash in the air anyway, I’d rather extract the silver first. It’s all just theory for now, anyway. I don’t have a desilvering plant yet.
cfb_de
Hello Benjamin,
Fixing in the dark increases the yield by the amount of the latent image. In daylight, not only is a latent image produced, but it is also already developed quite strongly physically.
Regarding the environment: Incinerators have exhaust gas purification systems and emit practically no dust. And even if they did: the volume of flue gas produced by burning the paper substrate is far greater than the tiny amount of silver in the emulsion. I consider the environmental impact of self-desilvering to be far greater.
Throw the roll in the general waste unless you want to desilver part of it beforehand purely out of academic interest.
Best regards,
Franz
