I had to video a wedding on a Sony digital video camera at the weekend, and rather than leave my Canon EOS 7D sat in the bag, I decided to string it up to a balcony and take a time-lapse sequence of the caterers preparing the reception venue (the Royal Marines Museum in Portsmouth) while I headed off to Portsmouth Cathedral to film the ceremony.
My time-lapse trigger can handle a maximum of 399 exposures. Knowing that the caterers had booked themselves roughly an hour to set up the venue, I set it to shoot 1 exposure every 10 secs - 3990 seconds giving me 1.1 hours of coverage. At 25 frames/sec, the 399 shots would generate 16 seconds of footage.
I read on this tutorial ( http://en.wikipedia.org/wiki/Time-lapse ) that to achieve smooth motion, your exposure time should be half of your interval time, so I set the exposure to 5 secs. After a couple of test shots it was clear that 5 secs was letting in a lot of light, so I reduced the aperture to F22 and knocked the ISO down to 100. It was still a tiny bit bright so I screwed on a polariser to take it down another stop to acceptable brightness.
I then set the remote to countdown, crossed my fingers and went off to film the ceremony. Thankfully, I found the sequence had exposed as intended when I got back to the reception venue a few hours later.
I then set up an action in Photoshop to crop the raw JPGs to HD widescreen (1920 x 1080) and used QuickTime Pro to convert the frames into a movie. I imported the resulting MOV into Premiere and used the motion effect to pan the HD movie across the SD (720 x 576) stage.
I'm happy with the result and think it'll make a nice little extra to splice among the other footage I shot during the day.
Thanks to Jennifer Bebb's 'Photo Fusion', Tom at Timescapes.org and Philip Bloom at F-Stop Academy for the inspiration.