Post date: Jan 6, 2015 4:20:31 AM
I’m thinking that a time-lapse video of my house-building project would be interesting. Of course, once the doors and windows are installed there won’t be much to see from the outside, so I better be prepared as soon as the digging starts.
Let’s assume that it will take a month to excavate, lay foundations, and erect walls.
That would be about 20 working days of 8 hours each, or 160 hours.
A short video should run about 5 minutes to display this process. Normal video is shot and displayed at 30 frames per second (fps), or 5 min x 60 second/minute x 30 frame/second = 9,000 total frames of video needed. But 10 fps is good for time lapse photography, so I will need 5 min x 60 second/minute x 10 frame/second = 3,000 frames for a 5 minute show.
These 3,000 frames would be taken over a period of 160 hours, tor 3,000 frames / 160 hour x 1 hour/60 min is about 1 frame per 20 seconds. In the language of the photographer, this is 20 seconds per frame.
There is a camera specifically made to capture time-lapse video: Brinno TLC200. About $130. I can mount it in the barn window, which faces my property across the road. Upside down at the top of the window will give me a slightly better view angle and make it less obvious from inside the barn. It appears that I can mount the camera upside down, then rotate the resulting video in iMovie.
Field of view of this camera is 59 degrees. It doesn’t get rave reviews, being called a cheap toy by some, but seems to fit my needs. I took a couple of still photos from the barn window just to see what the view will be.
I will test it overnight. Let's see: 12 hours x 60 minute/hour x 60 second/minute x 1 frame/2 second provides 21,600 frames. If played at 30 frames/second, playback will take 720 seconds, or about 12 minutes. I think we will get bored. Better take fewer frames, or a slower frame rate. Since I don't expect much to happen overnight, probably 1 frame per 5 seconds will be plenty.