An Introduction to Time-Lapse Photography
Photographing change. How is it possible? By its very nature, a photograph is scene frozen at a certain point in time. With time-lapse photography, however, a flower springs to life, a landscape is vitalized, and the sky comes alive. Time-lapses record images of a scene over an extended period of time, and in post-processing, those photos are turned into a movie and played back at a speed much faster than reality. In a time-lapse video, one notices details difficult or impossible to perceive with the human eye. That is why well-done time-lapse videos are so captivating. Here is one of my recent time-lapse videos.
Believe it or not, time-lapse videos aren't too hard to create if you have the right equipment. You should have the following items:
- DSLR camera
- A remote timer control (intervalometer)
- A sturdy tripod
- (ideally) An adapter/cord to plug in the camera
The intervalometer is a programmable control that tells the camera how many photos to take, how often, and how far apart. For my time-lapse videos of landscapes, I typically set my timer controller to take photos every 20 seconds. I turn off the limit so that the camera will continue to take photos until I stop it or the card fills up. This handy little controller can be quite pricey. There are less expensive third-party alternatives, but I can not testify to their quality since I have never used them.
A sturdy tripod is imperative. If you are photographing outside, then wind can shift your camera if you don't have a sturdy, heavy tripod. Those subtle movements will spoil the finished video, so do everything you can to give the camera a sturdy support. Birds may land on your camera making sturdiness even more essential.
Even though this is optional, I highly recommend having a power adapter so that you can plug your camera in. It is basically impossible to change out a battery in the middle of recording a series of time-lapse images. Consequently, without a power cord, you are quite limited in what you can do.
Spin that dial on your camera to Manual mode for the time-lapse session. You want to keep settings as consistent as possible to capture the changing lighting accurately. If you let the exposure be manually set, then the final time-lapse video will likely have flickering in it.
Getting an accurate exposure can be one of the most difficult parts of outdoor time-lapse photography. An exposure that has worked well for me so far for landscape time-lapses is a shutter speed of 1/250s, f/11 for the aperture, and ISO 200. It slightly overexposes a sunny midday. However, I'd rather slightly overexpose a sunny midday and get better details in the evening and morning. Experiment and use whatever works best for you. Unfortunately, using a constant exposure, you can only capture a very limited dynamic range. For example, here in Fairbanks, Alaska, we have 24 hours of daylight in the summer months. However, the light at night is dim enough that an exposure set for midday sun will not be able to capture any light for an hour or two each night. I suppose this could be compensated for with advanced time-lapse techniques and sophisticated video editing software, but I have not learned how to do it yet.
Switch your camera lens to manual focus and pre-focus it. If anything happens — such as natural lighting getting dim — that prevents your camera from focusing, that could stall your time-lapse. Also, moving objects may cause the camera's autofocus to vary from frame to frame causing inconsistency in the resulting video.
Since you are simply taking frames for a movie, you should use a very low resolution. I use the lowest resolution available on my camera, ~2.5 MP. When I compile the video, the resolution at which the video is output is significantly smaller than that. And the movie is still huge!
Time-lapse Video Compilation
After you have finished photographing the video's frames, download them to the computer. If you do not have Windows Live Movie Maker installed, get it here. Once it is installed, open it and open your time-lapse frames. Make sure they are in order in the program once they are imported. Next, select all of the frames and go the Edit tab and in the duration box, enter the length of time you want each frame to be displayed. If you did 0.5, then the video would play back at 2 frames/second. I usually do around 0.04 seconds/frame, which would be 25 frames/second. When you are done, go to the program menu in the top left corner of the screen. Go to Save movie..., and select the export preset that you want, select the location where you want to save it, hit "Save", and you're done!
Posted July 2, 2012 at 5:13AM by Eli Mitchell in Time Lapse, Photography, Video with 1 responses