CHAPTER XVII 



DEFECTS IN NEGATIVES AND PRINTS 



By Beverly Dudley 



DEFECTS IN NEGATIVES 



In the ideal case, defects in negatives do not occur; in practice defects of one kind or 

 another occur with sufficient frequency that the perfect negative is somewhat of a 

 rarity. It is seldom that the fault can be laid to the photosensitive materials. In 

 nearly every case the defects could have been avoided by cleanliness and complete 

 and proper attention to details in the exposing, developing, fixing, washing, and drying 

 of the negative. The best assurance that perfect negatives will be obtained 

 therefore is to take all precautions toward the prevention of occurrence of possible 

 defects. 



But even under the best of conditions, blemishes of one kind or another will occur, 

 and, when they do, a corrective or remedial measure is desired so that the film or plate 

 may be made to produce a satisfactory print. The prevention of defects in negatives 

 and the correction of these defects so as to produce satisfactory prints are, conse- 

 quently, two separate and distinct problems so far as the technique of manipulating 

 negatives is concerned. It is not always possible to find a remedy for certain types of 

 defects or blemishes in negatives, however, so that prevention of the cause of the 

 defect is the only true "remedy." But whether or not a defective negative can be 

 corrected through remedial measures, it is desirable to know the visual and photo- 

 graphic characteristics of the defect and the actual or probable cause, after which the 

 method of prevention and remedy can often be determined. This chapter deals with 

 such matters. 



To make this chapter as useful as possible the various defects which may occur in 

 negatives are classified into eleven groups depending (usually) upon the visual appear- 

 ance of the defects as seen by transmitted or reflected light. ^ The 1 1 groups into which 

 the defects are somewhat arbitrarily classified are: 



Blotches, lines, and streaks (page 508) 



Blurred negatives (page 512) 



Distorted images (page 514) 



Fogged negatives (page 517) 



Incorrect contrast (page 520) 



Incorrect density (page 522) 



Markings and spots (page 523) 



Mechanical or physical defects (page 529) 



Scum, slime, and deposits (page 532) 



Stains and discolorations (page 534) 



Uneveness (page 537) 



By determining into which of these 11 groups the defect falls and then further 

 following up the individual listings given under this grouping, information on a specific 

 defect may be obtained quickly. 



I See also Defects in Development, p. 361. 



507 



