The file B3208Fullerton_3_dem.tif contains a linear stretch of the DEM. To reconstruct the z-axis of the DEM in units of mm, 1) multiply TIFF by 0.0416389 2) Add -10.6179 The x & y scales are 0.030 mm / pixel. Maximum value for DEM, corresponding to TIFF value of 255: 0.00000 Minimum value for DEM, corresponding to TIFF value of 0: -10.6179