On 11/21/2013 01:47 AM, wrote:
On Monday, July 9, 2001 5:45:19 AM UTC-4, Klaus Schmaranz wrote:
Hi,

Ammonium thiosulfate is quite difficult to get (and expensive!)
because it's quite unstable... sofar, so good...

Is there any alternative to be used for a fixer that will be
capable of fully fixing modern emulsions (such as rapid fixer)?
Sodium thiosulfate doesn't do a perfect job on them, at least not
if they contain silver-iodide.

BTW - is there any source where I can find out which films and
papers need ammonium thiosulfate because of the iodide, and which
don't?

Thanks, Klaus.

There is a tiny but growing sub-culture alternative to ammonium
thiosulfate as a fixer, not spoken of in polite erudite professional
spaces. Everybody knows this elephant in the room is as brown as
Cafenol-C. Pardon my vulgarity, but iodized Sea Salt or Portuguese
Kitchen Salt (NOT TABLE and NOT REFINED) plus distilled water
supersaturated and filtered at 1.2 kg/litre density at 25-40 degrees
C for 4 to 18 hours has been used with some degree of success. An
odd thing is that a particular seaweed called "Dulse", rich in
potassium iodide, may be added to the soup for an extra special
secret "kick". Of course that's off the main highway off some back
road of electronic information, face down in a ditch with a tinfoil
hat kind of stuff. Not exactly something you would use for a
Presidential inauguration or anything other than art. You didn't
here it from me! Keep it on the D-L!

I used to use F-9 fixer. It is not as fast as Kodak Rapid Fixer, but it
is faster than F-5.

Water 600ml Hot water
Sodium Thiosulfate 360gr crystalline or 230gr anhydrous
Ammonium sulfate 60gr
Sodium Sulfite (anhydrous) 15gr
Acetic Acid 28% 48ml
Boric Acid 7.5gr
Potassium Alum (fine dodecahydrated) 15gr Do not use anhydrous
Cold water to make 1000ml

It is a hardening fixer. If you do not want hardening, you could reduce
or omit the Potassium Alum.


I prefer F-6 fixer for most things.

Water, about 50 Celsius (125° F.) 600 ml
Sodium Thiosulfate (Hypo) 240 g
Sodium Sulfite, desiccated 15 g
Acetic Acid, 28%; 48 ml
Kodalk 15 g
Potassium Alum 15 g
Cold water to make 1 liter

Here, too, you can omit the potassium alum if you do not need hardening.

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