Clearing Type 55 with Sodium Sulfite - What's the procedure?

Discussion in 'Film and Processing' started by bohdan_pryszlak, Oct 27, 2010.

  1. I just received a pound of powdered sodium sulfite. Two questions: 1. What proportion of chemical do I use with water to make a clearing solution. 2. How much time is needed to clear the Type 55 negs?
     
  2. I tried sodium sulphite before and it worked but it was too much trouble. I can't remember the strength but it took about 30 mins I seem to remember.
    I now do it by just soaking in plain water. It takes longer but works just as well and its easier. Grab a tray of water and place the neg in it. Leave it for 30mins and then come back, tip the water, refill and wait another 30 mins. After about 2hrs of doing this with some agitation every now and then, you will get rid of all the purple gunk and paper that was stuck to the neg and be left with a clean and neutral neg. Any traces of purple can be removed with more soaking in water. Dry as normal or you can treat with a hardener then wash some more etc. Don't be tempted to rub the gunk off or you will probably scratch the neg and remove the emulsion. I have soaked films up to 6 hours and more in some cases and they are all fine. Also don't use water that is too warm. The emulsion might just float off!
     
  3. to make the 18% soln, take the 16 ounces and mix it into 2000ml (70 ounces) of water. use it at around 70 degrees or so. doesn't take that long to clear a negative--couple of minutes. usually a little bit of gunk will be holding on--you can lightly pull that off. wash it for about 5 minutes, dip in wetting agent and dry. you can reuse the solution for a pretty long time, basically until it stops working.
     
  4. Thanks. I asked the question because prior to getting the sodium sulfite, I used Kodak Hypo Clearing Agent (and could only guess how long to leave it in). Then, because I was busy and didn't really care about the neg (bad shot) I left a neg in a cup of plain tap water for around two weeks. When I got around to checking it, the image had completely dissolved. Imagine that!
     
  5. I have a Polaroid tech pub for Type 665 (the baby brother of T55), and it says that you only need 60 seconds to sufficiently clear. It also recommends (as an optional step) giving it 2 minutes in hardened fixer, not to clear anything, but just to harden the emulsion. This step is after the clearing step, but before the 5 minute running water wash.
    P.S. As long as you keep air from the bottle, the sodium sulfite will last indefinitely.
     
  6. I can't remember the dilution either, but it did clear quickly. What messy stuff though. Used to keep a jug of it in my trunk at all times and put my negs in it until I got back to my darkroom. My trunk was always white from the dried sodium.
     
  7. i never used a hardener with it, but the emulsion is very touchy when you work with it. still have a bunch of type 55 in the studio I work in, but we mostly use the negs for proofing. on the occasions when we did use the neg, I just processed it immediately back in the lab. used a small tray to soak it in the soln, and used the same tray to wash it in, or I put it on a hanger and ran it through the wash tank & LFN in our deeptank. the pack film 665 uses a 12% soln and is a little different, mostly in the proofing end. the 55 you can proof without clearing. I shot a ton of type 55 when it was in production. it's pretty forgiving in terms of clearing. the only trick is to wear some gloves or else you'll track sodium sulfite all over the place. it dries as mentioned above--a fine white powder. very slippery stuff on your hands as well.
     

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