542 HANDBOOK OF PHOTOGRAPHY 



Fading. 



1. Distinguishing Characteristic. — Fading upon aging of the print, especiallj^ when 

 accompanied by yellow or brown discoloration. 



2. Cause.— Incomplete fixing or washing of the print. 



3. Prevention. — Proper fixing and washing. 



4. Remedy. — None. 



Finger Marks. 



1. Distinguishing Characteristic. — Imprint of fingers on the print, the finger marks 

 being (a) lighter or (6) darker than the rest of the print or (c) showing up upon aging 

 as a discoloration. 



2. Cause. — Impressing the fingers on the emulsion side of the print, especially 

 when the print is wet with processing solution, (o) If the finger marks are lighter 

 than the rest of the print, grease from the fingers may have been deposited on the 

 print prior to development. White fingerprints may also be due to touching the print 

 with hypo-contaminated fingers. (6) If the fingerprints are darker than the rest of 

 the print, grease from the fingers may have been deposited prior to development but 

 after fixing, (c) The appearance of finger marks, upon aging, as a discoloration indi- 

 cates inadequate washing, which may be due to grease preventing full action of the 

 wash water in removing hj'^po. 



3. Prevention. — Cleanliness in handling prints. Wearing rubber gloves or rubber 

 finger tips will prevent grease from fingers from reaching the print and, since the 

 rubber is smooth and nonabsorbent, will assist in keeping the hands clean. 



4. Remedy. — Make a new print. 



Freaks. Uneven Marks and Spots. 



1. Distinguishing Characteristic. — Uneven marks and spots, sometimes appearing 

 as if deposit of oil or grease has been made on the print. 



2. Cause. — (a) This may be due to uneven development, (6) a weak developing 

 solution, or (c) an actual deposit of oil or grease. 



3. Prevention. — Causes (a) and (6) may be prevented bj* proper development. 

 The developer should be properly compounded from pure and fresh materials. The 

 print should be immersed quickly and thoroughly in the developer and should be 

 agitated in solution so that even development, without the formation of air bells, 

 may result. In case (c) cleanliness is the only preventative. 



4. Remedy. — None; make new print. 



Greenish-brown Spots. 



1. Distinguishing Characteristic. — Greenish-brown spots on print. 



2. Cause. — These spots may be caused by (a) excessive amount of potassium 

 bromide in developer, (b) exhausted or old developer, or (c) overexposure. 



3. Prevention. — In (a) and (b), the defect may be prevented by using fresh and 

 properly prepared developers and by discarding exhausted or oxidized solutions. In 

 (c), correct exposure is the preventive. 



4. Remedy. — Make new print. 



White Spots on the Print. 



1. Distinguishing Characteristic. — (a) Small irregular white spots with sharply 

 defined edges. (6) Round white spots with fairly well-defined edges. 



2. Cause.— (a) These spots are often caused by dust or dirt either on the negative 

 itself or upon the glass top plate of the printer. If the particles of foreign matter are 

 on the emulsion side of the negative, they will produce sharp images on the print, 



