User manual

FastSCAN 29
5 Generating A Basic Surface
5.1 Basic Surface
Creating a Basic Surface removes redundant points in overlapping
sweeps. The scanned points can be repositioned and the minimum dis-
tance between them fixed to determine the amount of detail present in
the final surface.
When you have sufficiently edited your Raw Data click on the Basic
Surface icon to generate the Basic Surface. This uses default parame-
ter settings—you can change these parameters via the Generate Surface
dialog box—as outlined in the next section.
5.2 Basic Surface Parameters
Clicking on Edit/Generate or the Generate icon on the toolbar will bring
up the Generate Surface dialog box (Figure 19). This enables the user to
alter the characteristics of the Basic Surface before processing it.
5.2.1 Smoothing
When scanning, you will probably scan some parts of the surface with multiple
sweeps. These sweeps may not always align perfectly. Possible causes can include:
• small errors in the scanner measurements
• metal objects interfering with the magnetic locater
• the object or reference moving unintentionally during scanning.
The Smoothing parameter controls the degree of smoothing FastSCAN
TM
uses when
aligning sweeps. A low value creates a more detailed surface, but will fail to merge
the more widely separated sweeps. A higher value will merge sweeps better, but
remove more surface detail. Typically the smallest possible value that merges sweeps
correctly is ideal. Figure 20 shows the effect of different values.