January 17th, 2008 by Andrew
I finally got the Nikon EH-5a, the $70 power cord for my camera. It’s crazy that a cord can cost that much money, and all it does it supply my camera with power from a wall socket. I put it to use though, by running my camera all day on the 16th. I shot out my window towards the woods. Unfortunately it was a really clear day, the sun was never really in the picture, and the script didn’t start when it was supposed to (6am). Lots of problems. So the video’s kind of boring, but it was a good learning experience for when I do more time lapse videos.
Here’s the process I used. I installed gphoto on my ubuntu box. Gphoto allows you to control a capable camera with your computer. It’s a very neat program. There are tons of options I can play with, and I think everything is controllable through the software from aperture to shutter speed to white balance and ISO. I didn’t use any of its crazy capabilities though. I just wrote a bash script that called it every 60 seconds to take a picture and download it to the computer. I set the camera to aperture priority (A) mode. That way, the depth of field of the images wouldn’t change throughout the day, only the shutter speed.
Once I had a directory full of photos (just under 600), I ran ImageMagick’s “mogrify” command on them to resize them all to 600×366. From there, I used ImageMagick again, this time it’s “convert” command to turn all the jpegs into an mpeg, with 5 jpegs every second. This resulted in a movie that plays for a little over a minute that shows about 12 hours worth of time.