We have generated a large contour file on a 14 mile long project, encompassing 1500 acres flown in several missions. We have generated one large project, then split it into 3 projects. We have about 80 GCP’s done by surveyors that include elevation.
The issue is that the large single project has contour lines that are off, some by hundreds of feet vertically, while most are spot on. However, it seems that the contours to the split projects are all fine. What could be the reason? Aren’t the contour elevations derived from the GCP elevations? Each contour file also has the contour lines going different ways. If it is mapping the topography, shouldn’t they all lay the same way?