COLOR PHOTOGRAPHY 647 



Yellow Toner A Working Solution 



Yellow toner A — No. 1 1 oz. 25 cc. 



Yellow toner A — No. 2 1 oz. 25 cc. 



Standard ferricyanide solution IJ-z drams 5 cc. 



Add No. 1 to No. 2, stirring gently until any precipitate that maj^ appear is com- 

 pletely dissolved. 



This solution does not keep well when mixed, and onlj^ sufficient should be prepared 

 for prints in process. 



Toning the Red and Blue Prints. — The stripped-off black-and-white positive prints, 

 intended for the red and blue images, are placed together in one tray, and the red and 

 blue working solution (red and blue toner A), made up as outlined above, is added. 

 This preliminary A toning is actually a bleaching process. Care should be taken 

 that the films are thoroughly saturated with the solution. It is advisable to turn 

 them over repeatedly and to rock the tray to remove any air bubbles. 



A swab of absorbent cotton or a wide rubber-set varnish brush is very useful to 

 prevent all kinds of smear marks and uneven toning. The brush or swab should be 

 used almost continuously and must not be transferred from one solution to another. 

 The swabs can be thrown away after use and the brush thoroughly washed before 

 reuse. This practice is valuable in the first toning stages of all three colors. 



Swab the back to remove adherent back coating which may cause fading by 

 contamination. 



Keep the toning solutions cool. Their temperatures should not exceed 70°F. 

 With higher temperatures, loss of high lights may occur. 



Immersion in the A solution should be continued for at least 15 min. and, in any 

 case, until all the black silver is removed. When a print is thoroughly toned, it will 

 appear as a light greenish-brown image. It is then placed in running water and 

 thoroughly washed for about 10 min. As an alternative the print may be washed in 

 five complete changes of water in a tray. The washing operation after toning is of the 

 greatest importance and must not be slighted. 



It is also very essential that the hands be kept clean at all times in order not to 

 contaminate one solution by transferring another solution to it. 



After this washing, the red image is placed in the red toner B and allowed to tone 

 for about 10 min. (the toning proceeds to completion in this time; a little longer time 

 in the bath will do no harm). The solution is then poured off for use a second time, 

 and the print is immersed for 3 min. in a standard hypo solution. It is now washed for 

 about 15 min. in running water or in five or six complete changes of water. It is then 

 ready for assembling. 



Similarly the blue image is placed in the blue toner B and allowed to remain about 

 10 min., after which the toner is poured off for use a second time and the print is 

 immersed in a tray of weak hydrochloric acid solution for about 1 min. : Use one part 

 dilute solution with two parts water. The print is thoroughly washed in running water 

 for about 10 min. or in five complete changes of water, after which it is placed in a tray 

 containing standard hypo solution, made up as directed, until greenish tones have 

 changed to blue. It is then washed for about 20 min. or in six complete changes of 

 water. It is then ready for assembling; 



Toning the Yellow Image. — The yellow toning solution (yellow toner A) is supplied 

 in two solutions and must be made ready for use as described. The print to be toned 

 yellow is immersed in this solution for about 10 min. This work may be carried on 

 simultaneously with the blue and red toning operations, separate trays being used. 



After about 15 min. the solution is poured off into a graduate, and 10 cc. (3 drams) 

 standard hypo solution is added to every 50 cc. (2 oz.) working solution, and thor- 

 oughly mixed. Next wash the print for 1 min. in running water, or in one complete 



