Last Updated 00/01/19 1200 PST


Processing of Old Kodachrome K-12 Film as a Black & White Negative in the G-3 Rewind Tank by Martin W. Baumgarten ©2000

Let me quickly review the processing steps and times. It should take you one minute to pass the film from one reel to the other, regardless of film volume. Thus, if only processing ONE 50ft reel, the film will move slower thru the solutions, and the processing times will be cut down to 75% of the times for 100ft of film. The times mentioned in this breakdown and all information relative to rewind processing is based on a full 100ft load of film at 68°F (20°C). The steps outlined are for archival quality long term keeping of the film. Some short-cuts can be made for less-than-long-term keeping of the processed film. (e.g. just a quick exposure test or something etc) I do RECOMMEND that you splice film 2ft-3ft of film leader onto either end of the film. This will help insure even processing consistancy throughout the roll, otherwise, you'll get severe chemical effects on either end of the roll (meaning the entire roll to be processed, e.g. 50ft or 100ft).

  1. PRE-BATH Step - This is generally a solution to allow for even wetting of your and may contain an anti-fogging compound if you scratch-mix Kodak's PB-3 (Pre-Bath Formula #3) from Kodak's instructions. (A Photo-Flo or similar wetting agent can be used otherwise)...........4 minutes(passes)
  2. RINSE - Water only, four passes of the film..................4 minutes
  3. HIGH CONTRAST DEVELOPER - Recommended is Kodak formula D-19, but you can also use D-11 or D-8, or another manufacturer's high contrast developer which is similar in composition and strength. Your own results may vary. KODACHROME-II(old Process K-12, 1962-1973) - 5 minutes (5 passes). KODACHROME (old pre-1962 Process K-11 films) - 4 minutes (4 passes).
  4. RINSE - Water or use a simple Stop Bath made from 28% Acetic Acid mixed at 125ml per liter or quart of water. (ALWAYS add Acid to Water, not the other way around!) - 4 minutes (passes).
  5. FIXER - Fix in a hardening fixer similar to any rapid fix or Kodak's F-6 Fixer formula - 10 minutes.
  6. PRE-FINAL WASH - The remjet anti-halation backing on the Kodachrome film will not remove entirely during the developing process. You need to physically wipe it off using a piece of clean soft cotton cloth or flannel, that is kept very saturated with water and wipe it off a foot at a time. This will be tedious - but it has to be removed. Transfer the film to a plastic takeup reel and using a set of rewinds with a tray of solution between them, a photo grade sponge or chamois or soft white cotton flannel - prepare to wipe off the backing. If the backing is very stubborn to remove...then bath the film in a solution of simple BORAX and Water (made up at least 2 Tablespoons Borax per liter of water), and run this for 5 minutes (5 passes). Then with the Borax solution still on the film - wipe it off a foot at a time, applying firm pressure only to the base side of the film, taking care not to damage the emulsion. Once completed, return the film to the rewind tank for the Final Wash (first rinse & wipe out the rewind tank and reels since residue will remain from the backing).
  7. FINAL WASH - Washing in a rewind tank is incredibly long! (40 minutes/passes), so it's best to use Kodak Hypo Clearing Agent to shorten this time significantly. Rinse-in-water for one pass - 1 minute. Change to fresh water and Rinse-in-water for one pass - 1 minute. Change to fresh water and Rinse-in-water for two passes - 2 minutes. The above are necessary to remove the Borax solution and any Fixer residue compounds in high concentrations the following is to shorten your wash time overall. Pass-twice-thru in Hypo Clearing Agent 2 minutes Rinse-in-water for 6 passes - 6 minutes.
  8. DRYING AGENT - Although not mentioned in some steps/procedures, use Photo-Flo (or similar) wetting agent to aid in even drying. A few drops in a water bath of a liter or two to cover the film and run the film for two passes, will aid in preventing water spots. This helps especially in hard water areas - in very hard water or poor water areas - use distilled water for your final rinse and wetting agent (also consider mixing your developers in distilled water as well) - 2 minutes.
  9. DRYING THE FILM - Attach the end of the film to a film drying rack via a rubberband/paperclip combination, emulsion side up/base down. You can even use a film chamois dampened with the wetting agent and rung out, by very carefully pulling the film through the chamois. Keep the film in the wetting agent bath the entire time as the film is being pulled out of the tank and then onto the drying rack. Attach the paper clip and rubberband to the end of the film. Loop film as needed so that the clip will reach the next dowel. IF too much of a loop is required, then just add another rubberband/paperclip to compensate for the gap, to carry you to the next dowel. This will help prevent you from having to snip off too much of your film, especially if there are images towards the end.

Since the times for certain steps are long, I would recommend having a timer or large clock to watch so that you can keep-the-pace of the one-full-wind-per-minute method - music helps too. This way you aren't in the middle of the roll when all of a sudden, it's time to dump and move on to the next step. The "normal" photographic method of including the draining time within each step doesn't apply here, since sections of the film wouldn't receive the full treatment. So DRAIN after each processing step is complete - not a big rush - there is plenty of leeway - but do try to be consistent.

Best wishes,
Martin W. Baumgarten
Super8mm@aol.com


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