superfix

unregistered · 10-31-2006, 09:01 PM

Here is the exact formula and other details of the super fix that I
outlined in the thread on stop vs wash.

Formula:

Ammonium Hypo solution 200 ml/l

Sodium Sulfite (anh) 10 g/l

Ammonium Thiocyanate 10 g/l

Thiourea 10 g/l

As mixed the pH was 7.8 at 22.3 deg C. I adjusted it to 6.6 at 22.6
deg C with about 12 ml of 28% acetic acid. As mixed, it has a faint
ammonia odor, but after the pH is adjusted, it has no odor of
ammonia. The pH range of this fix should be about 6.3 - 6.7.

Test:

I compared it to F5 using Ilford HP5 plus film. At 22.6 deg C, the
film is cleared by the F5 in 5 mins and appeared fully fixed in 10
mins. The super fix cleared the film in 25 seconds, and fully fixed
it in 50 seconds. (it appeared completely fixed in the first 30
seconds but I let it go for the full 50 seconds)
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Sean · 10-31-2006, 09:02 PM

Comments from previous article system:

By David A. Goldfarb - 05:11 PM, 10-07-2004 Rating: None
Before trying it out, it would be a good idea to read the full thread, particularly the safety recommendations concerning Ammonium Thiocyanate--

http://www.photo.net/bboard/q-and-a...g?msg_id=009fBA

It's an interesting formula. I don't think I would use it, though, unless I were really developing film in quantity, where a couple of minutes of fix time saved might be more meaningful. TF-4 is fast enough for what I do.

By jdef - 03:26 PM, 02-22-2005 Rating: None
I've been using this fixer with My Rapid Universal developer, and getting fully developed and fixed film in less than 2min. Amazing. Absolutely no odor, and very simple to mix. I've been going from developer, to a quick fill and dump with water, and into the fix, and haven't seen any pinholing in my negatives. Thanks Ron!

By Photo Engineer - 10:23 PM, 02-01-2006 Rating: None
I am now up to Super Fix VII.

The goal of this project is to develop a fixer (no pun intended) that is faster fixing film and paper, but also is faster washing and gives better image stability. SFI shown above, does not achieve that goal yet.

SF VII seems to achieve that goal. I hope to release it ASAP.

BTW, the safety recommendations for thiourea are a concern due to reports of carcinogenicity notwithstanding the fact that thiourea is a common chemical produced by a variety of flowering plants. The concerns for thiocyanate are overstated in the thread due to confusion among some between thiocyanate and cyanide. Thiocyanate is present in many photographic processing solutions.

PE