Dry Plate Photography

The Light Farm Negative Emulsion Recipe #2

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'Rosie's Place'
TLF #2 Negative Emulsion

Enlargement of 5"x7" plate on Ilford Multigrade FB

  August 5, 2012
'TLF #2' is now updated.

  'TLF#2, 2nd ed.' Negative Emulsion — Pep Talk
  'TLF#2, 2nd ed.' Negative Emulsion — The Basics
  'TLF#2, 2nd ed.' Negative Emulsion — The Recipe

1st Edition Commentary:

I haven’t done as much work with TLF#2 as with TLF#1, although both 'Sunbow Over the Bayfront' (the image heading Section 7) and 'Rosie's Place' were made with the following recipe.   It is considerably faster than TLF#1 emulsion.  It is also prone to grain and fog, but I’m looking forward to learning its full potential.  I know I liked being able to catch the seagull in 'Sunbow...'  (The plate was shot at 1 sec and f/32.  I seriously overestimated the required exposure.  A second plate shot at 1/2 sec was better, but still a little dense, except the seagull lost patience with me.

At 1 sec and f/32, the plate is so dense it looks almost black on a light table, but it still produces a decent enlargement.  More work with this recipe is coming soon.

Full-Ammonia Bromide Emulsion Formula ("TLF #2, 1st edition")

(For an updated 2nd edition version of this recipe, please see the links from the glass-green box above)

1) Preheat a waterbath jacket on a magnetic hot plate to 45C. 2) Hold a waterbath pan at 40°C on a temperature-controlled hot plate. 3) Weigh out all chemicals.
Part I: In a 250ml beaker, prepare and hold at 40C:
  Distilled water, cold 22.5 ml
  Potassium bromide (KBr) 5.5 g
  Potassium iodide 1% (KI) 20 drops
  Gelatin 2.0 g

Procedure: Allow gelatin to soak in cold water 30 min; place in 40C waterbath, then stir while warming to 40C to dissolve. Add KBr and KI solution. Cover and leave sitting in the waterbath. Watch the temperature.

Part II: In a 80ml beaker, prepare and hold at room temperature:
Part A: Distilled water 15 ml
  Silver Nitrate 6 g
  Ammonium hydroxide, AR 29% 5ml *plus

Procedure: Add the ammonium hydroxide slowly with stirring until the brownish-black silver hydroxide precipitate that forms has just re-dissolved. Avoid excess ammonia. (*After 5ml, add the ammonia by the drop, stirring thoroughly after each addition, until the solution clears.)

Part III: In 250ml beaker, soak gelatin in cold water 15 minutes. (See procedure below.)
  Distilled water, cold 15 ml
  Gelatin 5.0 g

Precipitation, emulsification and first/physical ripening:

Procedure: Under safelight. Stir Part I rapidly* and with a syringe add half (10 ml) of Part II near the bottom of the beaker. Ripen 45 minutes at 45C, stirring for 30 seconds after 15 minutes and again 15 minutes later. (Procedure for Part III gelatin: Right after the second stirring, pour the cold water over the gelatin.)

Then, stirring rapidly, with a syringe add the rest of Part II to Part I. Stir 30 seconds and then add 2 drops 1% KI. Stir for one minute.

Pour this mixture over Part III and place the beaker in the waterbath. Warm to 45C with gentle stirring, then ripen 15 minutes. Pour into a ziploc sandwich baggie set in ice water in a lightproof container. Store overnight to a week under refrigeration.

Second Session

Preheat magnetic hot plate to 40C. Under safelight: Noodle the cold emulsion. Wash in ice water with twelve x 5 minutes each, water exchanges. While the noodles are still in the jelly bag, after the last washing use the rinsed out potato ricer to squeeze out as much water as possible. Then, roll the bag in a clean, dry terry towel and knead for a minute to get out more water. Open the jelly bag and turn the noodles out into a cold, stainless steel, lightproof container. (A 16oz film developing tank works great.) Sprinkle 7g dry gelatin over the top of the noodles and gently stir. Don’t worry about completely mixing it in. Store the noodles up to a week, or let rest at least 30 minutes under refrigeration, before digestion and coating.

Digestion/Chemical ripening and coating:

Preheat magnetic hot plate waterbath to 52C, with 250 ml beaker and stirring rod. Under safelight: Add the noodles to beaker and bring up to 40C with gentle stirring. Add 4 drops Steigmann’s gold sensitizer, stir one minute. Bring temperature up to 52C as quickly as possible without the waterbath ever overshooting 53C. (When the emulsion hits 50C, start to bring the temperature of the waterbath up to 53C. The emulsion will probably hit 52C before the waterbath hits 53C.)

With stirring, add 6 ml Everclear. Strain through two nested gold mesh coffee filters into a clean beaker. Coat at 32-35C. Experience with your own workflow will determine whether you need to keep the emulsion nested in a waterbath while you coat.

  • ‘stir rapidly’ is fast enough to see a vortex forming in the center of the beaker, but not so fast as to splash up emulsion. On my magnetic hot plate this is the #3 (of 9) setting. If you are a river person, it’s more of a riffle than a rapid.

Recipe modifications to try
  1. Increase silver and potassium bromide by same percentage (5% at a time).
  2. Split the Part II silver into three parts for three separate additions, maintaining same total ripening time.
  3. Vary the amount KI and/or the split of the additions.
  4. Increase the stirring during the first ripening.
  5. Vary the time between the first ripening and the second (time in refrigerator).
  6. Add the Steigmann’s sensitizer at a higher temperature (for example, 43C) and/or vary the amount added.

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