ABSTRACT
Good candidates for level nightscape time-lapses include anything in-between both periods of astronomical twilight, such as starry skies, the Milky Way, the Aurora Borealis/Australis, airglow and meteor showers. Every time-lapse video consists of an animated series of still images. There are two main steps in creating a time-lapse clip. The first step is to acquire the constituent images; the second step is to digitally assemble them into photographers' time-lapse video with a suitable frame rate. The time interval that passes between successive constituent images plays a major role in the actual time duration represented by each second of time-lapse. The shutter speed has a profound effect on the appearance of photographers' time-lapse video. Every time photographers' camera makes an exposure, it moves the lens’s internal diaphragm blades into position to produce the appropriate size opening. Each time it does so there are tiny differences in the actual positions where the blades come to rest.
