The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. Vol. XXXVII. Part Bl. Beijing 2008 
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Fig.7 the small object model 
Fig.8 One high precision 3D control field 
3.2 Experiments 
Fig.4 The forth four images of the model plane. 
They are photographed with the object distance 
further than the former. 
At the same time, we photographed a 3D control field with the 
same focal length so than we can compare the calibration 
precision of the plane calibration and the 3D calibration. And 
we make three-dimensional calibration result as a reference 
standard. 
Fig.5 one image of the model plane, 
where the model is not in the centre of the image. 
In order to analyze the influence factors, we designed several 
experiments. 
First, in order to analyze the influence of the camera model, we 
take three coefficients into account: the skewness, the ratio of 
focal length in the two axises and the distortion coefficients. In 
this experiment, we use the images in fig. 1. There is a table 
which can descript the result. 
In the table 1, we can get that: the coefficients: y, k3 and the 
ratio of the two focal length, effect on the calibration result 
slightly in the camera, and the appropriate model can get the 
right result quickly. In fact, we can choose approximate camera 
model without experiment one by one. We can choose the 
coefficient by significant analysis, which we won’t introduce 
here. 
experiment 1 
experiment 2 
experiment 3 
experiment 4 
experiment 3 
f*= fy, Y=0 
fx= fy, Y * 0 
f* * fy, Y=0 
fx=fy, y=0 
f x ^ fy, Y=0 
gr 
Il 
o 
k 3 =0 
k 3 =0 
k 3 ^ 0 
k 3 =0 
f* 
4093.1739 
4094.4707 
4093.5196 
4093.2611 
4093.2611 
fy 
4093.1739 
4094.4707 
4093. 1395 
4093.3723 
4093.3723 
Uo 
1593.6447 
1624.5627 
1624.2831 
1593.4418 
1593.4418 
Vo 
1199.3241 
1193.4379 
1193.2168 
1199.5787 
1199.5787 
ki 
-0.1196 
-0.1428 
-0.1276 
-0.1211 
-0.1211 
k 2 
0.0233 
0.3238 
0.0667 
0.0347 
0.0347 
k 3 
0 
0 
0 
0 
0 
Pi 
-0.0011 
-0.1273 
-0.0011 
-0.0021 
-0.0021