I am using a Nikon D2x with a Nikkor 12-24 f/4 lens. I was shooting on aperture priority, with the aperture wide open at f/4. I am also using a Nikon intervalometer which lets me set all kinds of things for timelapse.
For this particular sequence I was shooting a frame 1 second after the previous frame ended. Some of the previous frames were short, some were quite long. On average the exposures were about 1-2 seconds with 1 second in between each frame. Honestly I would have captured about 30% more lightning had I set it such that there was no delay between frames. I think the entire sequence was about 700+ frames.
As to the reason for shooting on aperture priority, well...it gets really technical really fast. If I shoot on Manual, my 'good exposures' end very quickly as the light dims during a sunset or a storm. If I shoot on Aperture Priority, the camera 'aims' for a good exposure, and when played back in sequence the goal is to have a baseline of good exposure. There is some 'flicker' which occurs as the 'good exposures' deviate from a visually non-perceptable average.
The interesting thing that happens during storm time-lapses shot on aperture-priority, is that as the scene darkens the exposures lengthen. As the exposures lengthen the amount of time the objects in the scene have to move. So, there is a perception that the clouds begin to move faster, when in reality the clouds are moving the same speed, but the exposures are longer, thereby resulting in an illusion that the clouds have moved a farther distance between frames.
I was shooting JPG+FINE and then downsampled it to 1280p. I ran the sequence through Lightroom and assembled it in QuickTime Pro.
