is the product of over twenty years of work by Peter Guth, Professor
of Oceanography at the US Naval Academy in Annapolis, MD. It contains
a staggering number of options and functions, to the point where
it may be overwhelming to the new user. But stick with it ...you're
almost certain to find multiple functions that are unique to it,
or that you'd have to pay quite a bit of money to duplicate with
other software. MicroDEM is 100% free.
Partial Display of the
Menus and Tools in MicroDEM
at least three versions of MicroDEM currently available:
5.1: An older version from 2001, back when it was also being
supported by the US Army as "Terrabase II". Available
from Fort Leonard Wood (http://www.wood.army.mil/TVC/DefaultPageContents/MicroDEM_TBII.htm).
May work better for slower computers.
6.03: The last official and fully debugged version of Terrabase
II; contains most of the functions of version 5.1, plus
new ones. Available at
7/8/9: Successive versions of MicroDEM have been released
as alpha software, with version 9 first appearing in September
2005. As alpha, the software does have bugs and quirks, but it
also has far more features than version 6.03. Available at
There is a full setup file for version 9 that is updated every
few months; updated versions of the executable and help files
are released on a fairly regular basis.
You can have different versions of the software installed on the
same computer (e.g. both version 6.03 and version 9), but it's
probably best to install the older version first so that the data
folder is updated properly for the newer version upon installation.
State Cartographers Office offers a simple tutorial
for creating perspective views with MicroDEM.
Extensive documentation exists for the older versions, most of
which is applicable to the most recent version as well. PDF
for versions 5.1 and 6.03 are available at
as are short video demonstrations of many
of the functions. Tip: Make sure you install the Camtasia Codec,
available at the site, in order to view the videos. Both versions
5.1 and 6.03 come with large help files as part of the installation.
There is no corresponding PDF manual for version 9, but the help
file is large and generally comprehensive, though newly-added
functions may take some time to be fully documented.
Guth also maintains a MicroDEM forum on Delphi (http://forums.delphiforums.com/microdem/start),
where you can post questions and bug reports.
There are simply
too many capabilities in MicroDEM to describe all of them fully.
What follows is an incomplete listing of many of its current capabilities.
The program's help file has more information. The functions listed
are those available in version 9; many, but not all, are also
available in version 6.
2-D DEM display
directly read in DEMs in many standard formats, and also includes
converters for other formats that it doesn't support natively.
It also writes DEMs in several different formats, including GeoTiff,
ASCII, DXF and ArcGrid. MD will re-interpolate DEMs to UTM or
geographic coordinates with the spacing of your choice.
Tip: MicroDEM will save DEMs in .DEM format, but
it's a native format that many other programs won't recognize
(one exception is Global Mapper).
sun angle and altitude
of aspect-based shading or sun angle shading
in greys, blue/green, six colors, and IHS
water coloring for flat areas / sea level
stereo anaglyph with user-adjustable exaggeration
variations from Display Parameters
(with user-definable colors for slope ranges)
variations from Tinted Maps
compass direction the slope is facing): Available in two different
forms from the Display Parameter menu and the View => Tinted
Maps => Aspect menu
when viewing or saving overlays
options from Tinted Maps include:
- Plan convexity
- Base level
Tip: If you export an image from MicroDEM, it will
be in screen resolution; to export in full resolution, make sure
you zoom the display to 1:1 using the "1" button at
the top of the map display.
Creates an overlay for a specified range of parameters, including
slope, elevation, aspect and relief. For example, you could find
all areas on DEM with slope between 20 and 45% on north-facing
slopes above 3000 feet.
Works with TARDEM to do drainage basin operations. Under this
menu item, will also plot downhill vectors on DEMs.
and displays contour lines with user-definable spacing and colors
Locates all points between user-specified values
- Finds slope
between two specified points
- Finds excessive
and steepest slopes on DEM
slope at a particular point
is actively working on these functions, and they may or may not
be working with any particular build of the program:
Line-of-Sight (slopes in green are visible from the selected vantage
LOS graph between two user-specified points
visible as green, invisible as red
mouse cursor along graph moves corresponding cursor along
available for arbitrary shape as Stream Profile
Fan (aka Viewshed)
area visible from a specific point on DEM
visible, hidden or both with user-specified colors and opacity
angle and distance of horizon blocking, plots on DEM
sun blocking for any day or days of year (when sun is visible
or masked by topography)
sunlight visibility DEM maps for user-defined area for any
day/days of year (very slow)
- Route coverage
what areas are visible as you travel along a route, as a
static map and animation
- Target coverage
percentage of a target area visible from a specific point
- Route observation
when a target area is visible
selection (arbitrary shape)
- Area calculation
- Range circles
- Offset plotting
(distance and bearing from a point)
- Datum shift:
Calculates shift between Primary and Secondary datums for any
point on map.
variation values: Calculates magnetic declination for any point
- UTM Grid
/ True north declination: Calculates variation between UTM grid
and true north
earth curvature: Calculates true distance compensating for earth's
- SPCS: Converts
location to State Plane Coordinate System
Many options leave drawing traces on DEMs and maps; to remove
many of these, use the Force
Redraw button. Overlays can be removed using the Overlay management
loads in multi-band Landsat, Quickbird and IKONOS imagery
band display (i.e choose which bands to display as Red, Green
- Band histograms,
scattergrams, ratios, differences
normalized differential indices NDWI, NDVI, NDSI, NBR
filtering for sharpening, edge detection
image component matrix and principal component calculation
"training" for category classification
of 30m color data with 15m panchromatic imagery
(Above) For a location double-clicked on a DEM,
the red curve shows the time for sunset; the green curve the time
for sunrise, and the blue curve the duration of daylight.
coordinate converter (projection/datum)
variation (both deviation and dip as function of position
DEM for holes
loading of databases (shapefile, DBF, CSV) associated with
loaded map. For shapefile DBF databases, you can plot the
features based on database variables with a variety of symbols
and colors, directly edit database entries, filter the database
using standard queries and then create a subset shapefile
of those filtered features.
Tip: While MicroDEM can handle raster files in
UTM or geographic coordinates without intervention, it requires
shapefiles and coordinate-related databases to be in geographic
coordinates (latitude/longitude). The Data Manipulation section
contains utilities to convert shapefiles from UTM to Lat/Lon and
View Menu (used
when DEM is loaded, with or without associated map):
- LOS: Calculates
elevation profile and line-of-sight visibility (green for
visible, red for not).
Creates a static oblique 3D view
Creates a rotatable and modifiable 3D view
Creates a 3D landscape as viewed from a particular location
(with the ability to drape photos or maps on top)
Similar to perspective, but creates 360-degree view
If you have installed the Gazetteer data, you can use it to
label peaks in the Panorama and Perspective views
Around: Creates an animation where you move around a point
while constantly looking in the direction of the point.
- Fly Through
/ Live Flying: Creates a fly-through animation that can be
saved as a movie. Fly Through follows a pre-determined route,
while Live Flying allows you to control the flight with keyboard
controls. VRML 3D Viewer (from toolbar): Allows creation of
3d VRML views
options (can be used on maps, photos and DEM views):
Draws a UTM or lat/lon grid on map
Allows several options, including downloading of TerraServer
map imagery for a particular location (DOQ or DRG); loading
of catalogued DEM or DRG imagery that correlates with the
currently displayed map; downloading of JPL TM imagery (432).
Allows overlay of US Census TIGER data or USGS Gazetteer info
(if properly installed and indexed)
If installed, loads in full USGS Gazetteer database 3D Map
Options: Sets parameters for 3D anaglyph display; also allows
de-collaring of USGS 24K topo quads
from USGS seamless server: Automatically creates DEM download
links that work with USGS seamless server (seamless.usgs.gov)
with GPS for real-time tracking, waypoint download/upload.
A separate section with many useful functions, including:
Export and Merging of a variety of types and formats of data
Numerous shapefile/database utilities, including projection/datum
conversions, adding field (including those from linked fields),
merging shapefiles, etc.
- See a
short tutorial on adding datum information
to a GeoTiff file with MicroDEM.
to index map data (raster, TIGER, Gazetteer) for easy data index
display and retrieval
of scanned raster files
creator and editor (points, lines and areas), but no advanced
features such as snap, drill, etc.
and marginalia tools, including many designed specifically for
geology and oceanography applications
and panorama views can be produced in anaglyphic or side-by-side