-37- 
Cyrax. 10 mm point-to-point spacing@60m 
Standard dev. 
Max error 
Number of 
points 
Target 1 
3 
16 
481687 
Target 2 
3 
12 
135449 
Target 3 
2 
16 
15944 
Target 4 
3 
17 
4221 
Target 5 
4 
20 
1954 
Table 4. Modelled precision for Cyrax 2500. 
The Cyrax show figures close to what can be found in the 
specification for the system. The modelled surface precision in 
the specifications is set to ±2 mm. Though good modelled 
precision, it can be noticed that maximum error, representing 
the point furthest away from the modelled plane, is as much as 
16 mm for two targets, both targets well within the 
recommended scanning range for the system 
Optech. 30 mm point-to-point spacing@60m 
Standard dev. 
Max error 
Number of 
points 
Target 1 
8 
35 
59131 
Target 2 
9 
46 
13959 
Target 3 
12 
43 
1751 
Target 4 
10 
65 
512 
Target 5 
11 
37 
92 
Table 5 
. Modelled precision for Optech ILRIS-3D. 
Optech. 10 mm point-to-point spacing@60m 
Standard dev. 
Max error 
Number of 
points 
Target 1 
8 
49 
307148 
Target 2 
8 
54 
72519 
Target 3 
12 
55 
9054 
Target 4 
9 
45 
2499 
Target 5 
8 
19 
156 
Table 6. Modelled precision for Optech ILRIS-3D. Only six 
repetitive measurements included. 
In the specifications for Optech ILRIS 3D the single point 
position accuracy is set to ± 7 to 10 mm. The test shows similar 
results. The maximum error, however is relatively big, but 
corresponding to the result for for the relationship between 
standard deviation and maximum error found for both the Cyrax 
and the Riegl systems 
Riegl. 75 mm point-to-point spacing@60m 
Standard dev. 
Max error 
Number of 
points 
Target 1 
20 
75 
7469 
Target 2 
19 
73 
2483 
Target 3 
20 
52 
285 
Table 7. Modelled precision for Riegl LMS-Z210. 
For the Riegl system only three of the test targets could be 
resolved. The standard deviation indicates a correspondence to 
the defined range accuracy specified for the Riegl system. The 
maximum error, however, must be considered quite big even 
though the relation between the maximum error and the 
standard deviation is smaller then for the Cyrax and Optech 
systems. 
“True distances” between the test targets were determined and 
used in comparison to distances decided with each system. This 
was used in evaluating the systems range accuracy. The result 
from the Trimble measurements was considered as the “true 
distances”. 
The modelled planes of the test targets for each system were 
used and between specific positions on the targets, point-to- 
point distances were recorded. Five different distances between 
each target were recorded. 
Cyrax 
Optech 
Riegl* 
Target 1 to 2 
2 mm 
2 mm 
24 mm 
Target 1 to 3 
1 mm 
10 mm 
16 mm 
Target 1 to 4 
1 mm 
9 mm 
- 
Target 1 to 5 
2 mm 
22 mm 
- 
Target 2 to 3 
2 mm 
8 mm 
7 mm 
Target 2 to 4 
1 mm 
8 mm 
- 
Target 2 to 5 
2 mm 
20 mm 
- 
Target 3 to 4 
1 mm 
1 mm 
- 
Target 3 to 5 
2 mm 
12 mm 
- 
Target 4 to 5 
2 mm 
12 mm 
- 
*The Riegl system point-to-point spacing was 75 mm at a range 
of 60 meter. 
Table 8. Differences between “true distances” and distances 
measured with tested systems. The figures are the 
average of five differences between each target. 30 
mm point-to-point spacing at a range of 60 meter. 
Cyrax 
Optech 
Target 1 to 2 
2 mm 
2 mm 
Target 1 to 3 
1 mm 
17 mm 
Target 1 to 4 
1 mm 
12 mm 
Target 1 to 5 
2 mm 
19 mm 
Target 2 to 3 
2 mm 
12 mm 
Target 2 to 4 
1 mm 
10 mm 
Target 2 to 5 
1 mm 
17 mm 
Target 3 to 4 
1 mm 
2 mm 
Target 3 to 5 
2 mm 
5 mm 
Target 4 to 5 
2 mm 
7 mm 
Table 9. Differences between “true distances” and distances 
measured with tested systems. The figures are the 
average of five differences between each target. 10 
mm point-to-point spacing at a range of 60 meter.