DEM
How to Create a 3D Rendition of a DEM With a Draped Image
NOTE: Prior to performing these steps with your data you would want to ensure that the DEM and image have the same geographic extents.
3D Terrain Model using Geographic Imager
We created a video to show that it is possible to use geospatial data and the 3D capabilities of Adobe Photoshop. It performs very well with a decent computer and video card.
In this video, a combination of Geographic Imager and Adobe Photoshop functions are used to open a DEM file using a script. The script also transforms a DEM into a 3D model and allows for an overlay of a colour model based on the data or a custom image (e.g. ortho image). Video after the jump.
Geographic Imager: Using Photoshop Info panel to explore elevation values
After importing a DEM file, you can always check the elevation value of a specific pixel in the Georeference dialog window. When you hover your mouse over the DEM image in the preview windw, you can get the image XY coordinate, latitude and longitude values, eastings and northing values (if the map is projected), as well as the elevation value.
Geographic Imager 3.2: Introduction to Terrain Shader, Part 3 - Applying Terrain Shader to multiple DEM files
If your workflow involves Terrain Shader, specifying a DEM schema is an important step, especially when dealing with mulitple DEM files.
When importing a single DEM file, Geographic Imager converts elevation values to gray scale values. For example, if the elevation range in your DEM file is between 0 and 2500 meters and the "Auto-stretched" option is selected, this range will be converted to the Adobe Photoshop gray scale range between black and white. As shown below, the black color is assigned to the lowest elevation value (0 meter) while the white color is assigned to the highest elevation value (2500 meters). For elevation values between 0 and 2500, Geographic Imager calculates and converts them into gray scale.
Geographic Imager 3.2: Introduction to Terrain Shader, Part 1
The upcoming release of Geographic Imager 3.2 introduces a new feature called Terrain Shader, used to apply color gradients and shaded relief to imported DEM images. Color gradients can be exported so that you can use them for other images or share them with other people.
You might want to take a look at our brief video about the Geographic Imager Terrain Shader on our Avenza YouTube channel.
