PUTTING THE SPOTLIGHT ON BASIC STAMP PROJECTS, HINTS & TIPS
■ BY JON WILLIAMS
CREATING TIME-LAPSE VIDEO
FOR AS LONG AS I CAN REMEMBER, my two favorite subjects have been
movies and electronics, and I'm especially happy when I get the opportunity
to combine the two. In the 80s, I saw an IMAX feature called "Chronos" that
just blew me away; the entire movie was shot using time-lapse cinematography
— it was breathtaking. I was so inspired by that movie that I built a 555
circuit to control my Super- 8 camera in single-frame mode. This let me
compress a four-hour drive from Los Angeles to Las Vegas into a three-minute
(one reel) Super- 8 movie. In the video age, time-lapse movies are not easily
produced with a video camera, but as my friend (and VFX wizard) John
demonstrated, one can easily create a time-lapse movie with a digital still
camera and video editing software.
MOVIES ARE ACTUALLY STILLS
When we go to the theater to see a "motion picture,"
what we're actually seeing is the projection of 24 still
images every second; it is our eyes and brain that blend
the images into what seems like smooth motion. It makes
sense, then, that we can take any series of images and
■ FIGURE 1. SIRCS 20-bit.
stitch them together to make a "movie." Of course we can,
animators do this day in and day out to make cartoons.
Video cameras are not set up (very well, anyway) to take
single frame images like film cameras, so we have to take
a different path: use a digital still camera.
When John showed me this trick, I actually laughed as it
is so elegantly simple. Using a digital still camera to create a
time-lapse movie is possible for two reasons: 1) The still
camera saves images as numbered files; and
2) Almost every video editing application has
the ability to take a group of numbered still
images and convert them to a video file. My
Sony digital still camera conveniently has
frame sizes that match standard and high-def
video frame sizes; the only thing I have to do
is trigger the camera at the desired interval.
Once I got hooked on this idea, I started
doing a bit of research and guess what? I'm
not the first to go down the path of creating
a time-lapse controller with the SX. In the
December 2007 issue, Joe DeMeyer created
a very nice, fairly sophisticated intervalometer
using the SX48, a DS1302 RTC, and a
Parallax serial LCD ( which uses an SX28!).
Mr. DeMeyer's requirements are greater than
mine so the SX48 made sense relative to
code space. My goal is to create a basic
intervalometer — a microcontroller version
of my original 555 device — and try to
squeeze the works (control code, LCD