IMAGENEX DT101Xi, Technical Manual

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Another output is shown below (Figure 4-13) and is produced by Hypack. The X axis shows the distance
from nadir and Y axis (left) shows the residual (or uncertainty) between computed reference average depth
and check lines at the 95% confidence level. As can be seen (and expected), the residual increases with
distance from nadir. The right axis shows the depth bias and shows a similar trend.
Figure 4-13 Hypack example
A number of other statistics and graphs (e.g. histograms) are produced by most MBES processing packages
and it is difficult to specify definitive acceptable statistical criteria since depth, bottom types, swath angle, etc.
all contribute to a changing picture. The Surveyor will make the decision as to whether the system is
performing within tolerance.
Note that Hypack (MBMAX64) provides a feature to process and analyse data from a single and dual head
MBES.