#Joining #GIS #digital #elevation #models #tiles

#Mosaic tool, the lifesaver tool for combining multiple #DEMs.

Back in my undergraduate engineering days, I struggled with unifying multiple DEMs–especially when my “study area” had a spread over multiple DEM tiles.  In this video, you’ll see how to combat this dilemma.  This video was made using the amazing and freely available data from Geogratis.

Now, when using the mosaic tool, make sure you do some due diligence.  I always advocate checking your projection.  That means that if you are mosaic-ing a small area, try converting your data to a planar projection (like UTM).

Another tip is to break up the mosaic process.  This means that if you have 20 tiles to mosaic, try doing two to three at a time instead of all at once.

Lastly, if you are finding the processing is slow, try changing your default ArcMap 10 Background Processing to Foreground Processing (click here to see my WordPress posting).  You will find this processing will make your ArcMap 10 experience very much like ArcMap 9.3 with the pop-up progress.  Personally, I like this pop up because I can see the processes and helps optimize my experience in ArcMap — rather than overtaxing the program.