Canon EF 8–15 mm f / 4L Fisheye USM - ideal lens for panorama photography. With an appropriate adapter (like nodal ninja) at 12mm for a full frame camera, it takes only 4 photos to stitch a full 360 panorama. With a Canon 5Ds you will get a equirect with 18x9Mpx.
Step-by-step guide to rendering a spherical 360° panorama in 3ds Max with Corona Renderer: camera setup, projection settings and output resolution.