Bas, Hüseyin Gazi
The diferantial equations for the influence of small errors of inner and outer orientation on the
image coordinates x, y are
dx = dxo - (x/f)df ^ (f/z)bx + (x/z)bz * (xy/f)do - f (1+x2 /f 2)d¢ + ydx
(1)
dy = dyo - (y/df * (f/z)by * (y/z)bz * £ ( 1* y?/P) do - (xy/f) do - xdx
(2)
where dx and dy represent the differences, at photo scale, between the corrected and measured
image coordinates of any point; x and y are measured comparator coordinates of point; f is
principal distance; dxo and dyo are the error of the determination of position of the principal point
from the fiducial marks in the photograph; df is the error in the principal distance; do, dó, dx are
small rotations about the X, Y and Z axes respectively; bx, by, bz are translations of the camera in
the X, Y and Z directions; and Z is object istance. In a similiar way differantial formulas can be
derived for arbitrary cases of photogrammetry. The differantial formulas of convergent case which
is fundamental importance for the terrastrial photogrammetry have been derived following:
dx = dxo - (x/f)df * (f/z)bx + (x/z)bz + y/f (x coso - f sin )do - f (1*x? /f 2)d6 * y/f( f cosb * x
sino )dx (3)
dy = dyo - (y/8df * (f/z)by + (y/2)bz + {(x/f sine ) - (1+ y2/f cost )}f do - (xy/f) dé - {x cose - f
sino (1* y?/P )}dx (4)
In equations (1) and (2) the unknown orientation errors dixo , dyo, df, ...... etc. are solved by means
of the same equations to correct the measured image coordinates. Control points are used in
solving these elements. Then corrected photo coordinates of all points on photo are obtained by
using these elements in matrix equations (5). The detail of application is explained in the Practical
Application paragraphs.
b X X dxo
- f/f* P y cf by bz/ y |-dflf y + dyo
(3)
f 0 0 0
Where f* = dD; (xy, IT
dD; = (do -do 1)
x*,y*- corrected image coordinates
X,Y = image coordinates measured in comparator and corrected for systematic
errors.
4 PRACTICAL APPLICATION
The present mathematical model has been applied to the normal case of close-range
photogrammetry. The used data in this application have been obtained from the test field the
detail of which was explained by Müftüoglu (1980). The application has been performed following
steps:
a. 25 test points were chosen from the test field.
b. Theoretical correct image coordinates of these points were computed by using the
geodetic coordinates of related points and the interior and exterior orientation data of
camera. The equations (6) and (7) have been used to compute these coordinates.
aii( X - Xo) * aio( Y - Yo) * ais( Z - Zo)
40 International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part B5. Amsterdam 2000.
(6)
(7)
Table
correc
photo
Tesi
poin
numb
3-
3-
6-
9-
9-