Panchromatic Negative Film for Motion Pictures

Photographic materials, from the standpoint of their sensitivity to light of different color, may be divided into three classes: ordinary, orthochromatic, and panchromatic. Those belonging to the class designated as ordinary, or blue sensitive, are sensitive only to blue and blue-green and do not respond appreciably to green, yellow, or red. As typical of this class may be mentioned Eastman Commercial Film and Eastman 40 Plates. By the use of suitable sensitizing dyes photographic materials can be made which, in addition to the blue sensitivity of the ordinary type, are sensitive also to green. They are usually referred to as orthochromatic and the Par and Super Speed Motion Picture Negative film fall in this class. The use of additional dye sensitizers gives a material which is sensitive also to yellow, orange, and red, thus providing photographic film which responds to the entire visible spectrum. These materials are designated as panchromatic and of this class Eastman Panchromatic Motion Picture Negative is a typical example. All of these materials in addition to their sensitivity to visible light are sensitive to those invisible radiations commonly referred to as the ultra-violet. By the use of certain sensitizing dyes the sensitivity can also be extended into the region of longer wave-lengths known as the infra-red. For a more complete discussion of this question of the color sensitivity of various types of photographic materials reference should be made to a paper by C. E. K. Mees.¹

Print ISSN

0096-6460

Published

1926-10

Content type

Original Research

DOI

10.5594/J06636