LP360 Digital Elevation Model Edge Mismatch

It may seem that there is an edge mismatch between Digital Elevation Model(s) (DEM) created with LP360 that is showing up when the grids are viewed in different software platforms. For instance, a user might see an offset between grids such as in the example below:

An example of two DEM raster files that appear to have an edge mismatch

An example of two DEM raster files that appear to have an edge mismatch

After further research into the matter it turns out the issue is purely a display problem. Each program displays the data using different methods. In the example above the value from a grid cell in one grid file does not get interpolated across the boundary to the neighboring grid cell in the neighboring grid file. The result is more dramatic when there is a big difference between the cell values manifesting itself as a drop off since the single grid value is used to display the entire cell.

Profile across grids

Profile across grids

A user can see this dramatic effect in the profile as seen in the example above.

If a user creates a single tile over the area same area and compares the two a user can see the display will now interpolate between the cells since they reside in the same grid file, but the original cell values will match, and in turn match the data from which it was generated.

Interpolating across cells in full file

Interpolating across cells in full file

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