Unequal-interval Time-lapse: Clock from Dave C Griffith on Vimeo.
In this case, a sine function was used to determine the time between frames based on the time which had elapsed from the start of the time lapse.
There are still some bugs to work out before I can create a full video made up of several clips. For really short intervals (where filling the camera buffer occurs) or really long intervals (where... I am actually not sure - I guess the camera goes to sleep?), things sort of fall apart. I think there is a ‘butter zone’ where this process will work nicely, although I have not yet determined the bounds for it. I also intend to try out other periodic functions (e.g., a sawtooth wave or triangle wave).
After shooting this video, I looked to see if anyone else has created what I was calling non-linear time-lapses. And the answer to that is yes… sort-of. There are some really interesting "non-linear" time-lapse projects out there. But it does not seem like anyone has posted anything quite the same as my clock (which I am now calling an ‘unequal-interval time-lapse’ – until I can think of something more pithy).
The coolest example of ‘non-linear’ time-lapse videos are the following videos from http://motionpeak.com/time-lapse. Watch them and see if you can work out how they did it. Scroll down for my attempt at an explanation (note that there website has some behind the scenes videos which are pretty interesting too).
As best as I can tell, the rig which moves the camera (either sliding along a track or turning for a pan) moves the camera quickly back and forth between frames to capture the scene at any given time from more than one location. So, for the truck example:
- a frame is captured at the front of the track (this appears at the start of the video);
- then a frame is captured at the rear of the track (this appears at the end of the video);
- then a frame is captured *almost* at the front of the track (this appears just after the start of the video);
- then a frame is captured *almost* at the rear of the track (this appears almost at the end of the video);
- this continues, with frames being captured alternatingly on the front and rear halves of the track with each one closer to the centre;
- the last frame captured during the shoot would be taken from the centre of the track and would appear be in the middle of the video.
Sorting those frames out and putting the video together must have been a nightmare!