D- 19. • .Rapid contrast for films and plates 



DK- 20.. Fine grain for films and plates 



DK- 50 .. General and Professional use on films and plates 



D-72. . .General use for films, plates and papers 



D- 76. . .Maximum speed with normal contrast and 



good shadow detail on films and plates 

 Note: ''Microdol'' is DK-20 with preservative added. 



''Dektol'' is D-72 with preservative added. 



Developers are prepared in 8-liter batches. For this purpose, an 

 automatic stirrer and a graduated 8-liter jug (with pouring lip) are pro- 

 vided for the use of the Chemist. The warm water is heated to about 50 C 

 in a 4-liter beaker over a Fischer burner, and then placed in the jug. The 

 stirrer is set in motion and the weighed chemicals added in the order listed , 

 each constituent being added only after the previous one has dissolved. When 

 all the chemicals are in solution, cold water is added to make 8 liters. The 

 inaccuracy in judging this from the graduation mark on the side of this jug 

 is not crucial. The solution is then poured into the stock bottles with the 

 aid of a large funnel provided for this purpose. 



Ingredients D-11 D- 19 DK-20 DK-50 D-72 D-76 



Distilled Water (50**C) 4L 4L 6L 4L 4L 6L 



Elon, Metol, or Photol 8.0 g 17.6 g 40.0 g 20.0 g 24.8 g 16.0 g 



Sodium Sulfite, anhydrous 600 g 768 g 800 g 240 g 360 g 800 g 



Hydroquinone 72.0 g 70. 4 g xxxx 20.0 g 96.0 g 40.0 g 



Kodalk xxxx xxxx 16.0 g 80.0 g xxxx xxxx 



Sodium Thiocyanate xxxx xxxx 8.0 g xxxx xxxx xxxx 



Sodium Carbonate, Monohydrate 234 g 449 g xxxx xxxx 632 g xxxx 



Potassium Bromide 40.0 g 40.0 g 4.0 g 4. g 15.2 g xxxx 



Borax (granular) xxxx xxxx xxxx xxxx xxxx 16.0 g 



Dissolve completely and dilute to 8 liters with cold distilled water. 



Preparation of Acid Fixing Bath with Hardener F-5: 



This is the only acid fix kept in stock since it is the general purpose 

 fixing bath, suitable for films, papers, and plates. For reasons of stability, 

 it is stored as two solutions which are mixed to order. One is a 30% Hypo 

 (Sodium Thiosulfate) solution and the other is the Hardener F-5A. Both are 

 kept in bottles on the pressure system, and mixed in a graduated cylinder in 

 the ratio 1 part Hardener to 4 parts Hypo. Solutions must be cool before 

 mixing. 



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