High Resolution 1:10,000 scale Mapping Strategy of Multi ... - NDMA

3) DEM 10m contour
interval has been
generated.
4) Contour
Generation
Manually digitized
for 10m
2m contour
interval has
been
generated.
Manually
digitized for 2m
5) Ortho Image 2.5 m GSD 0.5 m GSD 0.5 m GSD
Task Force Observations :
Table 11.5: Comparison of different satellite data
2m contour interval
generated.
Manually digitized for
2m
1. From the accuracy achieved during the process so far indicates that the
Data captured in 3 D mode from both the data will satisfy the positional
accuracy level required for 1 : 5,000 scale.
2. The accuracy of orthophotos evaluated against the limited ground points,
mainly in the plain area, indicates that Data captured in 2 D environment
will satisfy the positional accuracy level required for 1 : 6,000 – 1 : 8,000
scale
3. The height accuracy achieved indicates the accuracy level of 1 – 1.5
meters.
4. In general contour agrees if DEM is generated using manual mass points
and Break lines (2 m contour interval from DTM of Geo Eye and
Worldview – I; and 10 m contour interval from DTM of Cartosat – I).
5. Mass points need to be measured carefully at all strategic points and
Break lines need to delineated carefully.
6. Level of identification is better that Cartosat – I data in the study area.
7. But Field Verification is a must to Pick up Point features and Attribute other
features.
8. The final conclusion can be drawn only after evaluating the aspects of
identifying the features (Points and Linear) required for large scale, 3 D
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