garageCube

Does anyone have experience projecting onto a sphere?
I need to purchase a balloon for a one-sided projection.
What is the best shape and easiest to mount outdoors - A 16ft weather balloon or a 4m Advertising balloon?

I haven't tested it, but I assume Madmapper output is simply: Mesh warping - Spherise ?

Any advice appreciated

I once projected video onto a large balance ball. I shot the video using a 180 degree circular fisheye lens so when I projected it onto the balance ball it naturally reversed the lend distortion. No mesh warping needed!

yeah that makes sense but I don't have a fisheye for the projector

I used a fisheye lens for the video camera to shoot my footage. The projector had a normal lens. Because the footage is already distorted you don't need a special lens for the projector. The sphere that you project the image on will un-distort the image naturally. But you will, of course, need a fisheye lens for your camera.