On the weekend of 2013-09-06 to 09 I met up with Chris Georgia, Garrett Evans, Jared Blash, and Mike Taylor to spend some time camping and shooting the night sky along Maine's Bold Coast. The day time shots can be seen in this gallery: http://galleries.aaronpriestphoto.com/Coastal/Bold-Coast-Cutler-Maine/
To my knowledge, this is the world’s first spherical panorama of star trails in a vortex! Click the preview photo to see the whole sphere. It has taken several months and many attempts to come up with a method of shooting and stitching it, and I've discovered a few things that I can improve on my next attempt. I won’t give away all my secrets yet, but I’ll leave one big hint—there is an advantage to shooting spherical timelapses with a single camera/lens and a Panoneed robotic panning head over an array of several cameras. ;-) The disadvantage is that it takes a lot longer to shoot enough panoramas to create a timelapse and/or star trails. I only had 7.5hrs from astronomic dusk to dawn with consistent darkness to shoot everything for this shot, including the two long exposure panoramas of the Milky Way and the ground that are the base layer for the image. The rest were all short exposures of fewer stars for the trails that are blended on top. Several airplanes overhead and head lamps of us walking by, etc. had to be removed too.
Changing the focal length in steps between panoramas and not during one was a little bit of a challenge to automate, and batch stitching was a nightmare as I never did find a way to automate sliding the camera on the nodal slide, so there is some parallax to contend with for closer objects like the tree branches. Plus I had to gradually change the .xml stitching files and PTGui project files from one focal length to another across hundreds of panoramas to match the true focal length.
Technical details: shot with a Really Right Stuff TVC-34L tripod w/ TA-3-LC-HK leveling base & 192 FAS Package nodal slide, Panoneed robotic head, two Promote Controls, Nikon D700 camera, and Nikon 14-24mm f/2.8 lens.