ISSN:
0741-0581
Keywords:
Photography
;
Point source enlarger
;
Electron micrograph
;
Life and Medical Sciences
;
Cell & Developmental Biology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Natural Sciences in General
Notes:
Point source enlargers may cause unusual types of printing defects. One type is a large spot in the center of the enlarged picture field that sometimes appears when the edges of negatives are not adequately masked during printing. Another type is a blurry image caused by a defect in the polycontrast filter. The defect appears in the filter as a small spot of about 1/8-inch diameter, formed, presumably, by heat from the focused beam of the point source light. A spot defect of this type is difficult to see by a cursory visual examination of the filter and may develop unnoticed and persist for months before it is finally recognized.
Additional Material:
6 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jemt.1060010104
