and the winner is, with the 1 millionst topic about “limited by mainthread” … 
We have so many topics which mentioned the tLOD and some times cause enabled photogrammetry that.
Limit the tLOD, eg. start with 100 and then go stepwise higher. The Ultra-Setting is “200”…
We have also good wish topic about dynamic LOD: Dynamic LOD by altitude/flight level
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