d12e8b4e_sic_Dome_projection___Domerama__Spherical_mirror
[0] Scaling [Fisheye] Scaling is done from one projector only. [Spherical mirror] 
You can have better scaling, resolution and brightness by using more than one projectot (2 to 4 is common)
Geodesic Dome projection » Domerama
Spherical mirror