e of
itted
laf]
ii
P
Le nd
—
ps me
er
F
T
he dis-
an (6pm.
ion is
istance.
ange of
ng.
and the
fect is
erms in
nent of
to the
(4)
Where Xs, Ys, Zs, f, Xo, Zo, the internal and the
external orientation elements; kl, k2, the coeffi-
cients of radial distortion; ds, df, the
parameters of the offine deformation error; X,Y,Z,
the known coordinates of control points; x,y, the
image coordinates; 31,bi,ci(iz1,2,3), the
direction cosine; r, the radial radius of
distortion.
The indoor control field in which the survey
accuracy of control points reaches up O.1mm, in
the Photogrammetric Department of Wuhan
Technical University of Surveying and Mapping is
used to photograph and the program of space
resection of a single photograph for camera
calibration to resolve. The image coordinates are
measured on Stecometer and twenty or more marked
points on each photograph. the calibration results
are listed in table 2.
The distortion correction (dr=kle.r2+k2-.r4) of
different radial radius (r) for three photographic
distances (D) are presented in table 3.
Table 3 Distortion of 19/1318 after refit
r(mm) 10 20 30 40 50 60 70 80 90
D (m)
8.0 00 00 00 300 -01.-01. O0 03 211
4.0 00 -01—-04 ——-09 16 -25 -35 -41 43
2.5 00 -01 -06 -11 -21 -32 -43 -53 -55
It is shown from table 3 that (1) The closer the
photographic distance, the bigger the distortion
effect; (2) The biggest distortion effect is
0.01mm when the photographic distance is about 8m,
and now, the pair of picture photographed is yet
tolerated to operate in analogue mapper. But the
distortion effect must be corrected when
processing the picture photographed in distance
less than about 6m.
4 APPLICATION OF REFITTED PHOTOTHEODOLITE
19/1318 TO CLOSE RANGE PHOTOGRAMMETRY
4.1 Architectural photogrammetry
A lot of ancient architectures in China, such as
the temple, the tower and the courtyard and
others, are suited to photography by 19/1318. Many
ancient architectures and historical relics in
Summer Palace of Beijing have been taken. It is
found in photography that the middle-sized objects
(dimensions 1-10m), like the individual memorial
gatsway, and the decorated archway in architec-
tures and the copper lion, the stone horse and the
earthen figurines in the sculptures and so on, are
especially fitted to photography by refitted
19/1318.
A typical example, the copper lion at door of
Summer Palace, is taken by 19/1318 applying the
washer no. A. The photographic distance is Six
meters and the mean photographic scale 1:35. One
of photographs of copper lion is shown in Fig. 2
and its elevation map-
ped on stereometrograph
G in Fig. 3. The eleva-
tion has been checked
in field and accepted
up to standard.
It is of pratical
significance to point
out that if the object
as if cylinder is
photographed by UMK
10/1318 imported expen-
sively and the same
image scale is
wanted, the photogra-
phic distance shoud be
reduced by hal£. |
However, the dead area A B
is led to rise
because of the shorter Fig.4 The closer the
photographic distance phtographic distance,
(refer to Fig.4). the bigger the dead area
Fig.3 Elevation of the copper lion
mapped on the Steresmetrograph G
4.2 Industrial Photogrammetry
The application of refitted phototheodolite
19/1318 which is provided with the medium focal
length, to the industrial photogrammetry has the
great potentiality, too. Using it, the determina-
tion of the design location of engineering model
and the test of the hydranlic model etc. are
worked. These photographic distance are very
short, about 3-5m.
Table 2 Calibrated results of phototheodolite 19/1318 after refit
Mean photo. Calibrated internal element Coefficients of lens distor.
dis. D(m) f (mm) Xo (mm) Zo (mm) K1 K2
.0 198.69 0.127 -0.062 -2.492*1077 4.970-10^"
0 203.30 -0.021 0.211 -1.624-10-7 1.269-10-!!
5 209.65 0.147 -0.049 -2.054-10-7 1.602.101
