1. A concise explanation of the problem you're experiencing.
I am using global DEM from USGS. I have a globe setup and terrain exaggeration is "working". I am placing pins on the map using actual elevations from USGS.
If i set the terrain exaggeration value to 0[Flat Map] and offset the elevation so it is exactly 0, my pins lay directly on the surface like they should. The problem is that negative elevations are inside the planet. With exaggeration of 0[Flat Map] this is expected. When i set terrain exaggeration to 1 the terrain is exaggerated. The point is now inside the planet. The point is at 0 elevation which is actually about 4km above the surface due to this point being 4km below "sea level".
How does cesium compute terrain exaggeration. Do it read elevation data from the DEM?
4. The Cesium version you're using, your operating system and browser.
Cesium Version: 1.24
OS: Ubuntu 16.04 & OSX High Sierra
Web Browsers: Chrome(Current Stable), FireFox(Current Stable), and Safari.