My SRTM tiles have their elevations ranging from sea level i.e. 0m to 5,300m in Tanzania. My problem is that when I mosaic any two or more tiles, the elevation displayed on the Table of contents changes and the range becomes unbelievably high e.g. 0 - 65,000 and so the mosaic can't represent the terrain in my country.
SRTM data have pixel type of signed integer and pixel depth of 16 bit. The following image shows the property of an SRTM sample covering a region in Tanzania:
When you mosaic the data using Mosaic to New Raster tool, you need to define the output pixel type to be similar to the input raster data type which are signed integer and pixel depth of 16 bit, as you can see below:
The output should be correct:
Here is the property of the output final DEM: