time lapse photography

jamcas wrote on 7/11/2004, 8:51 PM
I was looking at some sony handycams and they have a timelapse photography option that produces "smoother" results than previous models etc ..

I was wondering if I set up a camera in a "busy" room and left it to film for a say 3 hours. is there a trick i can do in vegas to manipulate the 3 hours of video into 3 minutes of time lapse photography.

would exporting the video to images(10800sec x 25 fps = 270000 images)
and then importing in, say only every 60th image be the best way to do it ?


regards
JC

Comments

Chienworks wrote on 7/12/2004, 3:20 AM
It's a whole lot easier than that!

If you hold the Ctrl key down and drag the end of the clip to the left you can shrink it and speed it up to 4x. Add a Velocity envelope and set the speed to 300% and the clip now runs at 12x. This will get 3 hours down to 15 minutes. If you need to go faster, render this clip to a new DV .avi file and repeat the process as necessary. An additional 4x and 125% should end up at 3 minutes.

Right-mouse-button clicking on the clips and choosing "Disable resampling" may be a good idea while doing this process. It will speed up the rendering times and throw away unused frames instead of blending them together.
TheHappyFriar wrote on 7/12/2004, 6:26 AM
3rd party capture programs also capture in timelapse (like iuVCR). Most of those have a 30 day trial.
johnmeyer wrote on 7/12/2004, 7:53 AM
Actually, you may find it a little more complicated than you think, if you want to get really good time lapse results. Yes, you can change the speed of playback as has already been described, but you need to first look at the video that your camera has actually captured to see if it needs to be modified first, before you change its speed.

The problem is that the "time lapse" feature on video cameras usually lets the camera run for a few frames before it shuts off. On older cameras, you get almost one second of video each time the camera starts. This mode of operation was required because of the difficulty of building a camera that can set frame accurate start and stop points.

Your new camera perhaps has some circuitry that allows it to capture only one frame at a time. If so, then you don't need to read the rest of this post.

However if, after reviewing some sample footage captured in time lapse mode, you find that each capture consists of more than one frame of video, then you might want to download and use this script on your footage, prior to speeding up or slowing down the video:

Time Lapse Script

This script assumes that you capture the video from your camcorder so that each capture goes to a different file (i.e., you end up with hundreds of files, each only a few frames in length). The script then takes exactly one frame from each file. You then render this to a new file, and then stretch or compress that file to get the time lapse speed you want.

If you are really serious about time lapse, you should capture directly to a laptop using Scenalyzer (Scenalyzer) which has true time lapse capture, at any speed you want.
TheHappyFriar wrote on 7/12/2004, 10:14 AM
You could also take a camera (any camera), hook it up to your computer & then have your computer take the snapshots. I've got a Hi8 camera & I found if I leave a tape in there & don't do anything, the camera goes into "power save mode." AKA auto shutoff. I can override that by putting a tape in with the record tab on "protect". Then it works. :)
Chienworks wrote on 7/12/2004, 10:34 AM
I can override the auto power save mode on my cameras by not putting a tape in at all. Oddly enough, the audio stops working then. (Who makes these bizarre function decisions?) However, since the original audio is rarely used in time-lapse video this shouldn't be a problem.
johnmeyer wrote on 7/12/2004, 3:30 PM
I just remembered that I have a short MPEG file that I created by capturing to my laptop direclty using Scenalyzer. Here's the link:

Timelapse MPEG clip
jamcas wrote on 7/12/2004, 7:09 PM
thanks for your responses guys.
cheers
jc