I have been looking for a way to take a time-lapse of a moon rise or set with no overlap or gap between images. It isn't as simple as using a two minute interval. The moon's motion eastward is .55 arc seconds per minute, plus the moon's apparent size can vary by about 4 arc minutes. After some calculations I arrived at: interval = moon's apparent diameter in seconds / 13.9. This produced an image with slight overlap. I reduced the divisor and after some trial and error, I found that using a divisor of 13.55 worked well enough. This image was made with a William Optics RedCat on a fixed tripod using an intervalometer.