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2. Paramétrés of camera and sensitometric device: internal 
orientation elements; diameter of objective aperture; conventi 
onal number of spectrum zone where survey has been conducted; 
the transmission coefficient of the optical system along the 
principal optical axis; the law of luminance fall over the 
frame field; the earners light dissipation coefficient; effec 
tive exposure times during surveying and sensitometric wedge 
exposure; logarithms of* illumination intensity in energy units 
corresponding to sensitometric wedge fields ; corrections for 
deviation from the reciprocity lav/ and for differences in the 
spectral analysis of radiation during surveying and sensito- 
gram exposure. 
3. Survey conditions: date and Moscow time of the survey; 
declination of the Sun; height of photographing; atmospheric 
pressure at ocean level; terrain albedo; optical thickness of 
the atmosphere for the wavelength of 550 nm; tabulated values 
of the zonal terrain luminance in energy units as functions 
of the height of the Sun; tabulated values of haziness factor 
as a function of optical thickness of the atmosphere and height 
of the Sun; albedo of terrain, angle of sight on the object 
and azimuth of sighting plane relative to the Sun vertical. 
In addition to the above-mentioned data the following con 
ditions for statistical processing of the found values of 
photometric parameters should be present; coefficient of reduc 
tion of the size of the initial optical density values matrix; 
coordinates of the centers of the objects being studied (ter 
rain sections) and the number of elements of the initial matrix 
to be statistically.processed within the limits of each object. 
The algorithms for solving the problems of establishing 
relationships between various systems of coordinates, computa 
tion of the height and azimuth of the Sun during surveying are 
based on conventional photogrammetry and astronomy formulae. 
The algorithms for computation of brightness characteris 
tics of the terrain are based on the following two formulae: 
the formula establishing relationship between the brightness 
of the object and luminance of its image: 
e =x(fT Tr ° C '( B+ (1)