"recycling" old fogged film-an experiment

yulia_s_rey · Mar 18, 2013

Cleaning out my darkroom I found a half-used spool (~50') of +40 yr old film Valca 6 DIN Ortho (my Dad's) inside a box w/ no can, it was just out in the open. Being ever so curious I decided to try an experiment: Can it be "recycled?"
With the lights on, I fogged the heck out of it and developed it in Dektol 1:1. Once it was all black I washed it well, put the cover on the dev. tank and bleached. It was then washed well again and left it overnight to dry. The next day I put it in my slr and did some exposure tests in my backyard:
fast lens, long exposure: f 1.8 for 7 secs on a nice and bright sunny day. Dektol 1:1 for 3 min/wash/fix. I wonder now how other stocks would do, for example would a PAN still be panchromatic afterwards? Anyone ever played around w/ this?

dorff · Mar 18, 2013

What did you bleach with? I suppose the drying afterwards was done in darkness?

yulia_s_rey · Mar 18, 2013

CuCl for 15 min. All steps after bleach were done in darkness.

antmar · Mar 18, 2013

I really can't understand how you did it. Could you please tell us more about the procedure that you followed? Sounds very interesting.

PhotoJim · Mar 18, 2013

If I understand it right... he ruined it by fogging it and processing it... then in the dark, chemically bleached it and washed it, but leaving the now bleached silver salts remaining, which made them, once again, sensitive to light. It's an interesting idea.

yulia_s_rey · Mar 18, 2013

PhotoJim said:
If I understand it right... he ruined it by fogging it and processing it... then in the dark, chemically bleached it and washed it, but leaving the now bleached silver salts remaining, which made them, once again, sensitive to light. It's an interesting idea.

that's it... although just for the record, the film was already ruined when it was found.
here's the process at 68F:

1) You'll need old film that has been fogged or accidently exposed
2) Fog it under a strong light source
3) Spool it onto a tank reel & develop in strong developer until completely black (metallic silver)
4) Wash 2 min
5) Placed lid on tank and put in CuCl bleach (from B&H) for 15 min (silver halide, AgCl I suppose?)
6) Washed for +5 min
7) Opened inside the Darkroom and hung it to dry overnight.
8) Spooled it into a cartridge and did exposure tests.
I figured it be very slow working off reversal re-exposure as my guide. My initial guess was about 15 secs full daylight, but half of that was needed.
9) Developed & Fixed.

epatsellis · Mar 18, 2013

Interesting, this might help me salvage the box of 11x14 Efke 100 that accidentallly got fogged...I just can't bear the thought of throwing it away.

newcan1 · Mar 18, 2013

This is bogus. Bleaching the exposed, developed emulsion doesn't render it light sensitive again. Nice try.

AgX · Mar 18, 2013

Oxidizing and rehalogenizing metallic silver to gain a light-sensitive emulsion again is a well established process in photography.

Though one should not expect the sensitivity of the original emulsion.

newcan1 · Mar 18, 2013

I take it back then .. I didn't know this....so if I tried to sepia tone a print, and bleached and toned it in the dark, I would end up with no image? Or if I develop a black and white print, then bleach and redevelop in the dark, I would end up with no image? How do you "oxidize" the silver as well as re-halogenating? Does bleaching in CuCl oxidize as well as bleach?

Could this be done to remove base fog from film/paper? Say you had 400 ISO film with some fog. Could you develop and bleach it, and would the unexposed emulsion retain its former speed, and the rehalogenated base fog would no longer be fog, but a halide with very low speed?

I have some 1950's Ilford HP3 with so much fog that this would make an interesting experiment.

Interesting.

yulia_s_rey · Mar 18, 2013

no worries newcan1. To answer your questions from above: a) a latent image within a silver halide emulsion is lost in re-halogenizing. b)only the oxidized metallic silver is converted back to a halide. c) the film will not retain the same speed nor sensitivity to color. (although I could be wrong on the last one in terms of color sensitivity.) I like to think of it as starting from scratch with the stock, essentially it is just recycling something that would've otherwise gone to waste. The key is to intentionally fog your paper/film under a lot of light and develop it well (to oxidise the Ag fully) and then bleach it. Then run your exposure/dev tests.

Athiril · Mar 19, 2013

You can also expose the film to fumes of hydrochloric acid, or mix a little sulfuric acid + potassium permanganate + sodium chloride in a 'gassing tank' (tank reserved for the process), load it in, a spacer reel at bottom so film doesn't get wet, that's a dry process and works well too.

The other idea to do, is sleeve some film in plastic and leave it out in the sun for a week, to 'print-out', the grain will be much much finer. Gas bleach it back, ultra slow very fine grain film.

AgX · Mar 19, 2013

Interesting idea of that dry bleaching.

This is what PE wrote on the matter of rehalogenisation for re-using halide materials for first stage exposure:

Photo Engineer said:
This can be done, but it causes the film to lose all of its original sensitivity due to the destruction or disruption of the grains and the original chemical and spectral sensitization placed on the grains by the manufacturer. The film emulsion reverts to a simple blue sensitive emulsion with low speed, usually in the ISO 3 - 40 range if you are lucky. If it is high enough in iodide, you may actually fog the emulsion totally.

This subject comes up from time to time. It is a common minconception.

Also, no rehal bleach should be attempted with a color film or paper bleach. The ammonia content is enough to dissolve a fair portion of the finer grains rendering the film or paper useless. Any rehal process must be conducted in an environment free of any silver halide solvent.

PE

Herzeleid · Mar 19, 2013

Out of curiousity. This is all a wild guess bases on the idea that the silver in the emulsion is AgCl after CuCl bleach.

You expose the hell out of it, develop to black, bleach it so I assume no dyes were left in the gelatin emulsion that make the film panchromatic.
Assuming, CuCl bleach turns the silver halide in the emulsion to AgCl. This is the same silver halide in salt print/albumen.

If so, it is probably more sensitive to UV than visible light. But, salt prints are much more sensitive to visible light than most of the other alternative processes.
If so I would expect a visible image on the film before developing, if it is AgCl in the emulsion. Even developing might not be necessary.

If anybody would enlighten me, Is it possible that silver halide is AgCl in the emulsion after CuCl bleach?

Athiril · Mar 19, 2013

Logically it should be, in the presence of copper ions, the Br- can recombine with the Ag+ (ala transition lenses). But logically Chlorine should displace Bromine and Iodine in salts, and Bromine should displace Iodine if using a Bromide bleach.

Though, that's mostly assumption.

Also afaik, the simple act of washing doesn't remove spectral sensitisation (at least not all of it), haven't investigated bleaching though. Saw another user wash the antihalation out of some IR film, and the film maintained it's pan and IR sensitivitiy. Though I suppose it'd be dependant on how well fixed in place the sensitisation dyes are.

Herzeleid · Mar 19, 2013

Athiril said:
Logically it should be, in the presence of copper ions, the Br- can recombine with the Ag+ (ala transition lenses). But logically Chlorine should displace Bromine and Iodine in salts, and Bromine should displace Iodine if using a Bromide bleach.

Though, that's mostly assumption.

Also afaik, the simple act of washing doesn't remove spectral sensitisation (at least not all of it), haven't investigated bleaching though. Saw another user wash the antihalation out of some IR film, and the film maintained it's pan and IR sensitivitiy. Though I suppose it'd be dependant on how well fixed in place the sensitisation dyes are.

If the film is exposed to enough light to develop maximum black, and then developed in dektol 1+1, how much bromide would remain or would it even remain. Isn't bromide supposed to be removed during the development.

I agree, this is all based on assumptions, but sounds very plausible. Having an AgCl film is quite an interesting idea to me.

AgX · Mar 19, 2013

The adherence of spectral sensibilisator dyes differs between materials.
Not the least in dependance of the intented use of the emusion.

newcan1 · Mar 19, 2013

Why do you need to fully expose the film? I have some old HP3 that has a very dark fog, but I can get an image from it. Couldn't I develop some before using, bleach it, and presto - the fog would be gone? Wouldn't the rest of the emulsion (ie minus he fog) still work at its "original" (ie pre-treatment) speed? I wouldn't get any better image than before, but I wouldn't have to print through thick fog.

Also, would ferricyanide bleach work for this? Or EDTA bleach?

yulia_s_rey · Mar 19, 2013

From what I gather, it is essential to fully expose the film/paper in order to "recycle" it. I would think if your HP3 is partially fogged and you develop it, you won't achieve a "max black" before re-halogenization, otherwise the bleach will only act on the grains which are partially oxidized and you'll still have the same problem (only in reverse). In no way would it be possible to bring the film/paper back to its former glory. It is, as PE is quoted beforehand, "reverts[ed] to a simple blue sensitive emulsion with low speed, usually in the ISO 3 - 40 range if you are lucky." which makes sense. Initially, I wasn't sure about the color sensitivity. But now after reading the previous posts and a bit of research it makes sense as well as why it would not retain its original spectral sensitivity.
Not sure about the other bleaches as I have very limited experience with them as I usually use a Blix provided in kits.

newcan1 · Mar 19, 2013

Well I find this all very interesting. I have tons of waste imagesetter output; now I can scavenge all the pieces that are fully black, cut them into 6.5x9 cm rectangles, and bleach them to play with in my old Zeiss Ikon Maximar A. I could probably rustle up 100 or more cut sheets like this from the scrap output I have.

The film is imagesetter film, it's been developed and fixed, but that should not matter, should it? The imagesetter produces high contrast graphic output, so black is very black.

yulia_s_rey · Mar 19, 2013

As long as they are washed well (ideally no trace of fixer left) you're good to go. I'm going to continue doing this with scraps as well, I still have the Valca roll and countless feet of 16mm film that "spaghetti-ed" in my Canon Scopic- a pinhole camera is now in the making. While not an ideal stock, I like the whole recycling aspect of doing this. Some craft-makers make beautiful jewelry from stay-tabs from aluminum cans, no doubt the same can apply for a photographer using recycled scraps of film/paper to make a unique photograph.

Herzeleid · Mar 20, 2013

I can't seem to find the formula for copper chloride bleach. what is the formula you used for this process?

yulia_s_rey · Mar 20, 2013

I used Photographers' Formulary Cupric Chloride (from B&H here in New York) I remember a few years ago trying the diy method, it was 100g/100g copper sulphate/sodium chloride (pure) in 1 L h20, leaving it overnight and filtering it, it worked quite well.

Herzeleid · Mar 20, 2013

Thanks, I happen to have copper (II) chloride. I will try that in similar amounts.

newcan1 · Mar 23, 2013

Would it be at all safe to assume that the bleached film would be orthochromatic? If I take exposed imagesetter film that was red sensitive (open only under green safelight), and I develop it then bleach under a red safelight for re-use? It would be fun to cut a piece to use as 120 roll film, but it would be hard to bleach, wash and dry in total darkness.

"recycling" old fogged film-an experiment

Privacy & Transparency

Privacy & Transparency