Negative Exposure Control
It would be desirable to have negative exposure control on the basis of an exact science. Toward this end the functioning of the eye as it views a subject and the photographic reproduction of the subject is studied. The brightness of the subject is broken down into its components of reflectance (a constant) and incident illumination (a variable). The eye compensates for changes in the illumination. The “tone” of the object is based on its reflectance. It is this that determines the print density used to portray the object. Between the subject's fixed reflectance and the print's fixed density lies the variable of negative density. — A system is proposed whereby given reflectance in the subject is represented by fixed density in the negative. Operation of the system involves negative exposure control by measurement of incident light. Measurement of effective incident illumination is accomplished by a photoelectric meter specifically designed to respond to the three-dimensional characteristics of incident illumination. The system is free from many of the influences which tend to cause undesirable variations and errors in negative exposure. It provides a means of putting negative exposure control on the basis of an exact science.
- Print ISSN
- 0097-5834
- Published
- 1941-04
- Content type
- Original Research
- DOI
- 10.5594/J12915