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These innovations and improvements in automated navigation may
result in the production of
« gap-free coverages
. Symmetrical block photography ("symphotblocks" )s see
figure 1, 2 aid 3; see (6) and (7)
». pre-planned and pre-programmed exposure stations
("pin-pointed symphotblocks"); see figure 4; see (6) and (7)
3e Airborne sensor orientation,
(3a)...
(3b)...
being the technique of determining and recording some or
all of the six elements or outer orientation” of the
camera or sensor, at the instant of exposure or sensing
- either in space or in an earth coordinate system.
These elements are:
Xand Y ...... planimetrioc position,
Zecsosco0c00. altitude, or height, or both
«ouo e». angles of pitch and roll, or
deviation from verticality.
..0000000000 angle of yaw or azimuth, or northing,
J heading and drift
(see figures 5, 6, and 7)
Of the large number of combinational possibilities, three may
be of major importance in future:
determination of the "present position" (X,Y) of each exposure
station or data sensing, and recording of position. coordinates
(e.g. latitude and longitude ), together with the time instant,
along the frame of each aerial photograph, and on tape.
recording all six elements of outer orientation, at the
instant of each exposure or sensing (i.e. position X, Y;
altitude Z; attitude Œ, Q ; azimuth x) and recording
these, together with the time instant, along the frame
of each photograph.
5)
In case the data are recorded on a "rigid frame" recorder - e.g.
a photogrammetric camera - the three "elements of inner orientation"
are supposed to be known by means of camera calibration:
principal point ( x, y) and principal distance (c)