This is a great video that demonstrates what causes star trails (the rotation of the Earth, accumulating starlight…

This is a great video that demonstrates what causes star trails (the rotation of the Earth, accumulating starlight at different positions in a photo)

Originally shared by Dylan O’Donnell

This sequence shows you how a star trail photo is made. In the bad old days you’d have to keep the shutter open the whole time, but today far better results are achieved by “stacking” multiple short exposures into final image with trails. It also means you can animate the sequence like this, so for the one session you get the star trail photo, the animation of the earth rotating, and the animation of the frames being added together to build the star trail shot. Neat huh? Trippy music also by me, just a snippet of an unfinished thing I started. #astrophotography