GCP Distribution in the Survey Area
This article will describe the best practices for marking and measuring Ground Control Points based on the area to be measured.
GCP Distribution for elongated areas
Ground control points spreading recommendation in relation to desired topographic mapping scale for elongated projects:
|
Num. |
Map Scale |
2 GCP in both project side in each DL or DW [m] |
Accuracies in MSE in 95% [cm] |
Pixel foot print [cm] |
|
1 |
1:250 |
50.0 |
± 12 |
2.5 |
|
2 |
1:500 |
100.0 |
± 25 |
5.0 |
|
3 |
1:1250 |
250.0 |
± 30 |
12.5 |
|
4 |
1:2500 |
500.0 |
± 40 |
25.0 |
|
5 |
1:5000 |
1000.0 |
± 80 |
50.0 |
|
6 |
1:10,000 |
2000.0 |
± 120 |
100.0 |
GCP Distribution for polygonal areas
Ground control points distribution recommendation in relation to desired topographic mapping scale for polygonal (area) projects:
|
Num. |
Map Scale |
1 GCP in each square DL X DL in [m] |
Accuracies in MSE in 95% [cm] |
Pixel foot print [cm] |
|
1 |
1:250 |
50.0 |
± 12 |
2.5 |
|
2 |
1:500 |
100.0 |
± 25 |
5.0 |
|
3 |
1:1250 |
250.0 |
± 30 |
12.5 |
|
4 |
1:2500 |
500.0 |
± 40 |
25.0 |
|
5 |
1:5000 |
1000.0 |
± 80 |
50.0 |
|
6 |
1:10,000 |
2000.0 |
± 120 |
100.0 |
- Convex hull polygon consisting of GCP’s must cover the entire ROI circumference.
- User must add one control point in each DLxDL.
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