Table I: Sulfite-free Developers Using Ascorbic Acid or Sodium Ascorbate (Vitamin C) Original Improved A Improved B Borax A Borax B Stock A Stock B Sodium Carbonate 1 tsp - - - - - - Sodium Bicarbonate - 3/4 tsp 3/4 tsp - - - - Sodium Hydroxide - 15.5 ml 11 ml 17 ml 12.5 ml 68 ml 50 ml Borax - - - 1.5 tsp 1.5 tsp 2 tbs 2 tbs Ascorbic Acid 1/2 tsp 1/2 tsp - 1/2 tsp - 2 tsp - Sodium Ascorbate - - 3/4 tsp - 3/4 tsp - 1 tbs Metol or 1/16 tsp 1/16 tsp 1/16 tsp 1/16 tsp 1/16 tsp 1/4 tsp 1/4 tsp Phenidone solution 2.5 ml 2.5 ml 2.5 ml 2.5 ml 2.5 ml 10 ml 10 ml Add water to make 1 quart. Dissolve in order given. Sodium carbonate is PH-Plus. Substitute 30 ml of 20 solution of monohydrated sodium carbonate if desired. Sodium hydroxide is 10 solution. Use either metol or Phenidone but not both. Phenidone solution is 1/4 tsp in 80 ml denatured alcohol or 91 isopropyl rubbing alcohol. Table II: Sulfite-free Developers Using Ascorbic Acid or Sodium Ascorbate (Vitamin C) Improved A Improved B Borax A Borax B Stock A Stock B Sodium Bicarbonate 2.8 g 2.8 g - - - - Sodium Hydroxide 15.5 ml 11 ml 17 ml 12.5 ml 68 ml 50 ml Borax - - 6.1 g 6.1 g 24.4 g 24.4 g Ascorbic Acid 2 g - 2 g - 8 g - Sodium Ascorbate - 2.25 g - 2.25 g - 9 g Metol or 0.2 g 0.2 g 0.2 g 0.2 g 0.8 g 0.8 g Phenidone solution 2.5 ml 2.5 ml 2.5 ml 2.5 ml 10 ml 10 ml Add water to make 1 quart. Dissolve in order given. Sodium hydroxide is 10 solution. Use either metol or Phenidone but not both. Phenidone solution is 0.65 g in 80 ml denatured alcohol or 91 isopropyl rubbing alcohol. Dilute stock solution 1+3 for film, 1+1 for paper.

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