Excellent sleuthing! And thanks for all the hard work on this.
This makes me wonder if we should have a default IBL for the Sandbox with a balanced and full range of lighting information, while also not adding color into the ambient lighting.
We want to be able to judge the quality of glTF materials without them appearing under-lit and without a significant color cast.
It’s nice to be able to drag-n-drop a DDS in, but it’s an annoyance to have to do when iterating. Especially since with Max2Bablyon we have Export&Run.