Quote Ingolifs (

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fish eye lens
Can be used for dome projection (home simulators/planetariums). Some people do use this.
Quote Ingolifs (

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cubemap
Needed for skybox export, which I use.
Quote Ingolifs (

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I doubt being able to overlay the orbits of the solar system in a different colour would be an exceedingly difficult task.
Maybe, and I agree that it would be a good feature to have.