April 12, 2012

Fixer

There's absolutely no way to invent an environmental safe fixer. No way at all! Problem are the unused and removed silver salts from the emulsion, they come from the film and they are toxic for micro organisms. If you don't remove these salts, you do not fix! The commonly used thiosulphates (hypo) alone are of very, very low toxicity, the silver ions are the problem.
Kitchen salt doesn't work at all as a fixer, beleave me, I tested it. And I don't know of any reliable source that can confirm kitchen salt works as a fixer with modern films. And even if it should work (again, it doesn't!) still you would have to dispose the used fixer environmentally safe!!!

So use your regular fixer without bad consious. A "bio"-fix does NOT  and can NOT exist. Proper disposal and re-using the toxic and expensive silver is the only way that makes sense, for us AND the environment.

I'm really getting tired answering this question: salt does NOT work as a fixer. No matter how often it is claimed. This is a myth coming from the 19th century!!!

Important update, see next post: Fixer 2. I don't delete this post, it's part of my own Caffenol history.

6 comments:

Anonymous said...

Kitchen salt works as a fixer... at least somewhat. I made a test with film leader from a roll of tri-x. I made a developed black spot on it with some used developer, washed it and let it sit in heavily salted water.

Eventually it cleared... But... It took between one and two weeks to clear! And I also changed the salt water a few times as some of my earlier tests showed that the clearing process will stop if it isn't changed.

Another problem was the it seemed to start bleaching the developed silver back to gray undeveloped stuff... Not fully but a bit anyway.

So... It seems to work, but it is very, very , very unefficient!

Anonymous said...

I have read (but not tried)of a method that causes the silver to precipitate out. It involved placing "steel wool" in a bucket and pouring the fixer through it. The silver ions in solution exchange with the iron ions in the steel wool. The silver ions combine with sulfur and form a precipitate that falls to the bottom of the can as 'sludge'.
This can be sent for processing to decontaminate.

Cheers,
Glenn

Tobias Pohl said...

That´s really true! I worked on the same issue, but no chance to do it. I talked to ex agfa chemicans and engeneers. NO WAY!

But there is a alternative dev.
Wineol - Film developing with red wine

http://analogdigital-ganzegal.blogspot.de/2012/02/wineol-redwine-for-bw-film-developing.html

Cheers
Tobias

imagesfrugales said...

"But there is an alternative dev."

There are many, many, many alternative devs ;-)

Tobias, 100 g/l (that is a huge amount!) anhydrous washing soda with 2 g/l Vit-C and 60 minutes rotation = permanent agitation probably make a developer from everything, be it red wine, dino blood or pebbles :-DD

imagesfrugales said...

Anon: after 2 weeks "fixing" with salt you probably have already dissolved parts of the emulsion and/or bacteria have eaten it :-D

Glen: it works, but: you must use staining steel wool, stainless steel wool won't work. Still you have to dispose the silver mud, and are you sure you removed all the silver or just a part?

If you have no possibility to dispose the used fixer, you might ask a lab. They should be happy, you bring them money, the silver price is high. They will recycle the silver.

Tobias Pohl said...

"...probably make a developer from everything, be it red wine, dino blood or pebbles :-DD"

Your are right, this was my first trial and a starting point. During my Holiday workshop at Cote Azur a bought a huge amount redwine and did some normal agitate and stand dev´s. After reducing the time i will reduce the washing soda as well. I will blo the new results soon.
And shure i will also taste the dino blood as well :-)