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Figure 50: Aerial view of marsh test 2
One of the advantages of using vector data which has already been controlled to
cut the photography into a mosaic of polygons is the extent to which the set data
points mirror detail that would be extremely difficult to identify using automatic
methods (such as the outline of the drain, visible in the indent on the eastern edge
of the above polygon). The values for this larger sample area, although it
contained more tree cover that the first sample, remained consistent with all four
samples with a gradual incline from shade values to the expected values for marsh
in the red colour band (following page):
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