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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)
