As we take baby steps into the planetarium world, the professionals out there are making advances in shooting for domed theaters. Here is a small version of a 2304X2304 image that was taken by Planetarium Hamburg.
Here is their description: "6mm f5.6 lens together with a custom
developed linear optical relay of about 1.7 which allows the entire 220°
FoV to be used on the RED sensor".