Pig. 1. Schematic Diagram of Photometric Measurements 
Process 
1 - radiation reflected by object 
2 - transformation of radiation by atmosphere and photo 
system optics 
3 - optical image of object 
4 - photo-chemical treatment of film 
5 - photo picture of object 
6 - optical image of sensitometric wedge 
7 - photo-chemical treatment of sensitogram 
8 - photo picture of sensitogram 
There exists a functional relationship between the bright 
ness of the object and intensity of illumination of its optic 
image in the focal plane of the photo camera. In view of this, 
the idea of the photographic photometry technique is reduced 
to determining the intensity of illumination of the optical 
image of the object through comparing the values of optical 
density of the images of the object and sensitogram fields on 
one and the same instrument. 
Photometric measurements technique 
The automated version of the photometric measurements 
technique developed by the State Center "Priroda" makes it 
possible to determine the values of the zonal luminance factor 
(ZLP) and contrast between adjacent elements of terrain and 
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