Peachtree Street Time Lapse

I’ve always liked time lapse films. They can be a really powerful way to look at things with a fresh perspective. I’m not alone in thinking that. Some of the most popular videos on Vimeo are well constructed time lapse sequences. While I have shot some in the past, they have been sort of accidental, by products of trying to make other pictures. 

Lately I’ve gotten interested in learning how to shoot well made time lapse films. It is learning process for me so here is some of the problems I’ve worked out.

Flicker. The biggest obstacle to shooting smooth time lapse is avoiding flicker in the footage. In general flicker is caused by the lens aperture not being exactly consistent each shot. Even on a high quality lens the aperture can vary 1/4-1/3 of a stop in different frames. When shooting stills that is not such a big deal but in a sequence of images the variation produces flicker. The tighter the aperture the worse the flicker will be. With big f numbers the aperture blades travel far and there is more room for error. There are two strategies to avoid flicker.

1 Use an open aperture. If you can shoot at 5.6 or 4 or even more open the aperture blades don’t have far to travel and the error between shots is likely to be minimal. That is fine when you are shooting in the evening but to use that technique in the day requires ND filters. 

2 Use lenses with a manual aperture. On Nikon cameras you can just use older lenses. For us Canon shooters it’s not so easy. A regular EOS lens will not keep the aperture locked down even when the mirror is locked up. There are some excellent cine lenses for EOS cameras that have manual apertures. They are also really really expensive. 

There is a work around for EOS lenses. Set the camera manually, then press the depth of field preview button and while holding it down press the lens release button and turn the lens slightly but don’t detach it. You just want to move the lens on the body far enough to disconnect the electrical contacts. The lens will stay stopped down. 

Then assuming you are using a reasonable shutter speed, you can shoot flicker free.

Stephen Alvarez

Sewanee, TN