Ordnance Survey DEM

Lidar DSM/DTM at 2 m, 1 m, and 0.5 m resolutions.  This is so much better than the older data, you should use this if at all possible.

MICRODEM reads the United Kingdom Ordnance Survey DEM in NTF v.2.0 format, in several variants:

The program will ignore a leading DT for 5 km tiles and a DTM for 20 km tile file names. You cannot rename the files; the registration information is in the file name. If you want descriptive names, put the files into directories.

The import assumes the grid size and spacing, and gets the DEM location from the file name. It ignores the header portion of the file, and jumps directly to the data grid. It has been tested with a number of  DEMs (at least 5 for the 50 m posting, 1 for the 10 m, and 2 for the 5 m postings.). Should there be importing problems, I would need a copy of the offending DEM to fix the code.

The British National grid uses a transverse Mercator projection, but differs from UTM:

For the British National Grid, see

Landform Panorama:

OS Terrain 50


Last revised 10/24/2017