During this Christmas break, I saw a gentleman in Yosemte using a robot attached digital camera.
It's a 2 dimensional swing movement control machine. I guess it can be programed to move and control the camera for multiple exposures.
Should be very quick and convenient and precise for panning and panoramic.
I was told it's not home made, but purchased from somewhere off the shelf.
Anyone has more detail about this? Seems a good alternatives for extra -wide angle photography.