und 
is 
age 
cient. 
“hina 
id 120 
alysed. 
nation, 
aph is 
th the 
imation 
spans 
ass of 
ves of 
Fig.1 
greater 
e along 
and in 
y. The 
ement. 
rrected 
gramme- 
ger the 
owever, 
larger 
ts. We 
g-force 
n that 
as the 
rve of 
smaller 
dicates 
part of 
nds. 
  
  
  
56.317 um 
- Length change along x 
56.29r 
56.277 
Se zs NO. of film 
. + 1 4 6 A “3 i L 12 
56.91r 
Length change along y 
56.89} 
56.87F : ; 
Fig.2 Change of film 120 
  
2.2 Determination of Internal Orientation (Inclu- 
ding the Lens Distortion) of Non-Metric Camera 
The determination is aimed at a research for the 
change of the internal orientation (including the 
lens distortion) of non-metric camera in all 
course of photography. For this purpose, the same 
external geometric condition should be kept in 
photography. Thus, the camera is fixed as far as 
possible; The 3-D control field is repeatedly 
photographed; the points with same number and 
location in each photograph are used (19 points 
every picture) and image coordinates measured by 
same operator. The season for adopting these steps 
is due to the fact that the influences of changes 
of internal and external orientation for camera 
are correlated each other. The application of same 
photographic condition could be deemed that the 
effect of change of external orientation is 
basically same for each film. Equally, the 
selection of similar number and location of 
control points and the observation by same 
operator could be thought that the effects of the 
distribution of control points and the 
jdentification and measurement errors of picture 
points are primarily similar for each film too. 
Thus it is good for us to compare the relative 
variation of parameters (including the lens 
distortion coefficients) of non-metric camera 
computed by each film and appraise their stability 
in the process of photography of all film roll. 
The film are measured on the large tool microscope 
which can read by estimate the coordinate up to 
0.1um. Then the solution is done with following 
procedure 
(1) correction of film deformation 
xsx'(dx'/dx), y=y'(dy'/dy) 
Where x',y', measured image coordinates;  X,Y, 
corrected image coordinates; dx,dy, frame spans 
measured in film along the lines of x and y; dx’, 
dy*, corresponding practical frame spans of 
camera. 
(2) The internal and the external orientation ‚of 
camera are calculated by the space resection with 
a single photograph: 
ai (X-Xs)+b1 (Y-Ys)+c1(Z-Zs) 
  
x-x,+Ax= f 
a2 (X-Xs) *b2(Y-Ys) *c2(Z-Zs) 
a3 (X-Xs) *b3 (Y-Ys) *c3 (Z-Zs) 
Y-Y. tAy- Î 
  
a2(X-Xs) *b2(Y-Ys) *c2(Z-Zs) 
where axsk1(x-x.)r?,ys-kl(y-y.)r?,r?z(x-x.)?*t(y-y. )? 
Every symbol in equation is known to all. 
The photographs are measured and calculated about 
three intervals. The computational results are 
listed in table 1 and 2 separately 
Table 2 Principal distance and lens distortion of 
  
  
"seagull"4D 
NO. of film i. 4 6 9 12 
f (mm) 75.820 375.993 75.831 75.879. 75.850 
k1-1076 4.730 5.480 5.938 6.113 5.835 
residual(mm) 0.016 0.014 0.014 0.014 0.013 
  
Note * The residual of point means the standard 
error estimated by the coordinate residuals of 
image points in space resection computation 
according to equation m-t/my7*my? 
** The coordinates of principal point is not 
listed in table because there aren't collimation 
marks in camera and a known point is used to be 
origin in computation. 
2.3 Discussions 
2.3.1 The effect of lens distortion in non- 
metric camera: Based on the results calibrated 
above, The effect of lens distortion of two non- 
metric camera made in China is shown in table 3, 
in which the data of a Japanese camera is also 
given for comparison. 
Table 3 The Mean Calibrated Data and The Biggest 
Influence of lens Distortion of Three Camera 
  
  
Model formal Princ. Pho. Distor. biggest dr 
of dis. dis. coef. influence 
camera (mmemm) (mm) (m) (k1) (mm) 
MAMIYA C330 36-24 55 6 1.2:107°* 0.095 
(Japan) 
Seagull DF-1 36-24 58 6 .1.7-10% * 0.292 
(China) 
Seagull 4D 55:55 75 6  5.6-10 ^ 0.208 
(China) 
  
*The data is supplied by photogrammetric Depart- 
ment of Wuhan Technical University Of Surveying 
And Mapping 
Table 1 Principal distance and lens distortion of "seagull" DF-1 
  
  
NO. of film 4 7 11 . 14 20 22. 24 23) .30 .32 36 
f (mm) 58.765 .786 .843 .853 .801 .811 .840 .802 .840 .795 .832 
K1:1075 3.510 .958 .728 .653 ‚675 .845 .774 .557 .669 .668 .791 
residual(mm) 0.007 .007 .008 .006 .008 
  
   
.007 .008 .008 .005 .007 .008 .009