DEFECTS IN NEGATIVES AND PRINTS 509 



Branched Lines with Black Spots. — (See Static Markings, page 511.) 

 Brush Marks. 



1. Distinguishing Characteristic. — Streaks and blotches resembling brush marks. 



2. Cause. — Incorrectly compounded or exhausted developing solutions are the 

 most probable causes for such streaks. 



3. Prevention. — Use of correctly compounded developing solutions of full concen- 

 tration for the negative being processed. Prepared developers are available which, 

 when dissolved in the proper amount of water will give solutions of the proper strength 

 and compounding. Certain developers for tray development are not recommended 

 by the manufacturers for tank development when diluted. 



4. Remedy. — Probably none other than retouching the negative or print. 



Dark or Black Streaks or Blotches. 



Streaks and blotches occur in several different forms, so that it is not possible 

 to identify the cause of the defect quite so readily as in the case of certain other defects 

 of negatives. For this reason, means for the prevention of the defect sometimes may 

 be difficult to determine. The streaks and blotches may take various shapes, may be 

 sharply defined with sharp edges, or may be poorlj^ defined with edges of varying 

 gradation. 



lA. Distinguishing Characteristic. — Dark or black streaks or blotches, usually 

 with shaded edges. 



2A. Cause. — Uneven development which may be due to: (o) failure to immerse a 

 portion of the film during development; (b) protection of a portion of the negative 

 against development by intimate contact with another negative or the surface of the 

 developing tank or tray; (c) failure to provide relative motion between negative, solu- 

 tion, and developing tray or tank. 



SA. Prevention.- — Immerse negative quickly and completely in developing solution. 

 During the first few minvites of development, maintain relative motion between nega- 

 tive and developing solution by agitating solution, moving the negative in the solution, 

 or rocking or tilting the developing tray or tank. 



4A. Remedy. — ^Local intensification of the less dense portions of the negative may 

 be employed to assist in bringing the negative to its proper and uniform densitj\ 



IB. Distinguishing Characteristic. — Irregular dark blotch, resembling splashed 

 or spattered liquid. 



2B. Cause. — Developer splashed on negative prior to development. The action 

 of this splash of developing solution for a longer time than developer acting on the rest 

 of the negative produces a darker spot, otherwise uncolored if nonstaining developer 

 is used. 



35. Prevention. — Cleanliness and careful habits in developing. Do not permit 

 negatives to lie around the darkroom, especially if unprotected. 



4:3. Remedy. — ^Local reduction may sometimes be used to advantage in this case 

 (see chapter on Intensification and Reduction). 



IC. Distinguishing Characteristic. — Dark or opaque streaks or blotches. 



2C. Cause. — Dirty developing tray or tank or, perhaps, the use of fixing tray or 

 tank for developing. 



3C Prevention. — Cleanliness and systematic habits in developing. Where a single 

 tank is used for carrying out all processing of the negative, it may be advisable to run 

 clear water through the tank between processing solutions. For single-tank process- 

 ing, special care should be given to the matter of thoroughly cleaning the tank and 

 plate or film supports after each use. 



4C Remedy. — Probably none, other than local reduction. 



