I have a large model exported from a software with a lot of nested instances. I added a shadow generator with defaults and added most meshes to its renderList. The console recommends to use Exponential Shadow Maps (ESM) which look also a lot nicer ("VSM are now replaced by ESM. Please use useExponentialShadowMap instead").
With ESM enabled, the scene turns mostly black because shadows are rendered also on top of those meshes that cast that part of the shadow. The issue only disappears when the shadow generator has only a single mesh in the renderList. See here:
Is this a bug? Is ESM not yet stable (although the console recommends using it)? Is there a work-around?
Another question: My model is mostly static. Are shadow maps regenerated at every frame or only when something (lights, meshes) changes?