Making a time-lapse movie--that is, taking a bunch of still photos in sequence and putting them together into a video--seems like a simple task. Unfortunately, any time you deal with digital video, things get complicated fast, with terms like codec and bitrate joining the party before you know what hit you. In this article I won't go into all the technical stuff--that would require a whole series of articles--but I'll give you the basics of making your own time-lapse film.
Taking your time-lapse stills
The aim of a time-lapse movie is to compress a long event, like a flower growing, a painting being painted, or a game of chess, into a short video in which the action appears to transpire rapidly. Three things will determined how long your final video will be:
The duration of the event being captured
The amount of time between photos
The frame rate of the final video
It might take a flower 30 days to bloom, whereas a chess game might last only an hour. The interval between photos will depend on how much things change from one moment to the next. A flower might look no different at 1 p.m. than it did at noon, but after 24 hours will have changed slightly, so a good interval might be one day. In a chess match, however, pieces may be moved several times each minute, so ten seconds might be a better interval. Consider your subject carefully, and err on the side of an interval that's too short rather than too long--if you have too many photos you can always discard some, but if you don't have enough you can't go back and take more.
"Frame rate" means how many pictures--frames--are shown every second. We use the term "FPS" (Frames Per Second) to describe the frame rate. Television in the U.S. has a frame rate of about 30 FPS--thirty frames per second--whereas cinemas show most movies at 24 FPS. Frame rates this high are necessary to make live action appear smooth instead of jerky, but for your movie a lower frame rate may be acceptable, especially if your subject moves a lot from one frame to the next. The higher your frame rate, the shorter your final movie will be. If you take one photo of the flower every day for 30 days, you'll have a total of 30 frames. If you show them at 30 frames per second, your movie will be only one second long. If you choose 15 FPS instead, your movie will be two seconds long. As you can see, the longer you want your movie to be, the more frames you'll need to have--a two-minute movie at 15 FPS, for example, would need 1,800 frames (120 seconds x 15 FPS = 1,800). You'll have to take all of these things into consideration before you start taking your photos. Don't forget, however, that a five-second movie of a flower growing may be a lot more interesting than a five-minute movie of the same.
Taking the photos
You'll need a digital camera, and I highly recommend a tripod. If you don't have a tripod, you could make one out of a soda bottle and a few cents worth of parts. Otherwise, find a very steady surface to put the camera on, and make sure nothing moves it while you're taking your photos.
If your interval is long, it's easy to just set an alarm to remind yourself to press the shutter button, say, every 24 hours. If it's shorter, however, it could be a drag having to press the button every hour, minute, or more. Solving this problem is tricky, and depends on what kind of camera you have. If you have a webcam, Microsoft offers a free Webcam Timershot PowerToy that will automatically take a picture at specified intervals. If your camera isn't a webcam, your camera might have a built-in timer that can take multiple shots at specified intervals--check its user's manual--or you may have to use software specifically for your camera. My Nikon D50, for example, came with Nikon Camera Control software that has this feature. You may have to do some internet searching to find the solution that works for your camera.
In the end, you should have anywhere from a few dozen to a few thousand photos to make your movie out of. It will help to have them all in a folder separate from any other files.
Putting them all together: Windows Movie Maker
The easiest way to put all of your photos together into a time-lapse movie is with Microsoft's free Windows Movie Maker. You probably already have it installed on your computer--look in the Accessories menu under Programs on the Start menu. If not, you can download it from Microsoft. For our purposes, Movie Maker has one very important limitation: When turning photos into a movie, the minimum "picture duration" is 0.125 seconds, which translates to 8 frames per second. Take a look at a clock and try to count from 1 to 8 in the time it takes for the second hand to tick off one second--that's one frame for each number you counted out. It may seem pretty fast, but depending on what you've captured it may or may not be fast enough. To figure out how long your movie will be at this frame rate (in seconds) just divide the number of frames you've captured by 8. I recommend giving it a try, and seeing how it turns out.
Once you've started Windows Movie Maker, the first thing to do is import all of your pictures. In Windows XP, click on Import Pictures under Capture Video in the left-hand pane. In Windows Vista, you'll click on Pictures under the Tasks and Import headings. In the dialog that appears, navigate to the folder where you saved your photos and select them all--a quick shortcut is to click on the first one and then press Ctrl+A--then click in the Import button. Movie Maker will load all of them into the center pane.
The aim of a time-lapse movie is to compress a long event, like a flower growing, a painting being painted, or a game of chess, into a short video in which the action appears to transpire rapidly. Three things will determined how long your final video will be:
The duration of the event being captured
The amount of time between photos
The frame rate of the final video
It might take a flower 30 days to bloom, whereas a chess game might last only an hour. The interval between photos will depend on how much things change from one moment to the next. A flower might look no different at 1 p.m. than it did at noon, but after 24 hours will have changed slightly, so a good interval might be one day. In a chess match, however, pieces may be moved several times each minute, so ten seconds might be a better interval. Consider your subject carefully, and err on the side of an interval that's too short rather than too long--if you have too many photos you can always discard some, but if you don't have enough you can't go back and take more.
"Frame rate" means how many pictures--frames--are shown every second. We use the term "FPS" (Frames Per Second) to describe the frame rate. Television in the U.S. has a frame rate of about 30 FPS--thirty frames per second--whereas cinemas show most movies at 24 FPS. Frame rates this high are necessary to make live action appear smooth instead of jerky, but for your movie a lower frame rate may be acceptable, especially if your subject moves a lot from one frame to the next. The higher your frame rate, the shorter your final movie will be. If you take one photo of the flower every day for 30 days, you'll have a total of 30 frames. If you show them at 30 frames per second, your movie will be only one second long. If you choose 15 FPS instead, your movie will be two seconds long. As you can see, the longer you want your movie to be, the more frames you'll need to have--a two-minute movie at 15 FPS, for example, would need 1,800 frames (120 seconds x 15 FPS = 1,800). You'll have to take all of these things into consideration before you start taking your photos. Don't forget, however, that a five-second movie of a flower growing may be a lot more interesting than a five-minute movie of the same.
Taking the photos
You'll need a digital camera, and I highly recommend a tripod. If you don't have a tripod, you could make one out of a soda bottle and a few cents worth of parts. Otherwise, find a very steady surface to put the camera on, and make sure nothing moves it while you're taking your photos.
If your interval is long, it's easy to just set an alarm to remind yourself to press the shutter button, say, every 24 hours. If it's shorter, however, it could be a drag having to press the button every hour, minute, or more. Solving this problem is tricky, and depends on what kind of camera you have. If you have a webcam, Microsoft offers a free Webcam Timershot PowerToy that will automatically take a picture at specified intervals. If your camera isn't a webcam, your camera might have a built-in timer that can take multiple shots at specified intervals--check its user's manual--or you may have to use software specifically for your camera. My Nikon D50, for example, came with Nikon Camera Control software that has this feature. You may have to do some internet searching to find the solution that works for your camera.
In the end, you should have anywhere from a few dozen to a few thousand photos to make your movie out of. It will help to have them all in a folder separate from any other files.
Putting them all together: Windows Movie Maker
The easiest way to put all of your photos together into a time-lapse movie is with Microsoft's free Windows Movie Maker. You probably already have it installed on your computer--look in the Accessories menu under Programs on the Start menu. If not, you can download it from Microsoft. For our purposes, Movie Maker has one very important limitation: When turning photos into a movie, the minimum "picture duration" is 0.125 seconds, which translates to 8 frames per second. Take a look at a clock and try to count from 1 to 8 in the time it takes for the second hand to tick off one second--that's one frame for each number you counted out. It may seem pretty fast, but depending on what you've captured it may or may not be fast enough. To figure out how long your movie will be at this frame rate (in seconds) just divide the number of frames you've captured by 8. I recommend giving it a try, and seeing how it turns out.
Once you've started Windows Movie Maker, the first thing to do is import all of your pictures. In Windows XP, click on Import Pictures under Capture Video in the left-hand pane. In Windows Vista, you'll click on Pictures under the Tasks and Import headings. In the dialog that appears, navigate to the folder where you saved your photos and select them all--a quick shortcut is to click on the first one and then press Ctrl+A--then click in the Import button. Movie Maker will load all of them into the center pane.
Now we have to choose what will be our frame rate. Go to the Tools menu and click on Options... and then on the Advanced tab. The Picture duration field controls how long each photo will be shown by default. The lowest it will go is 0.125 (one eighth of a second, or 8 FPS), and you can adjust it by an eighth of a second at a time by clicking the up and down arrows. When you're finished, click on OK.
Now it's time to add your photos to the "storyboard." Select them all (again, click on the first one and then press Ctrl+A) and drag them to the leftmost box at the bottom of the screen. This operation may take some time if you have many photos. When it's done you'll see your photos lined up in the storyboard.
With that, the hard work is done. You can now preview your time-lapse movie by clicking on the Play button on the video player on the right. The preview might be less smooth than your final video will be. If you decide that the frame rate is too fast or too slow, the easiest way to fix it is to remove your pictures from the storyboard, go to Options again and change the Picture duration, and then add your photos to the storyboard again.
A distinct advantage of using Windows Movie Maker is now that you've got your time-lapse movie you can add things like music, titles, and credits to your movie. These are pretty easy operations and I won't discuss them here, but play around and see what you can come up with.
When you're finished, it's time to save your final video. In Windows XP you'll use the commands under "Finish Movie" on the left. In Vista they're under "Publish to." Choose the option that matches what you want to do with the final video and follow the steps. If in doubt, choose the Computer option, which will allow you to save the movie as a file on your hard drive, with which you can then do as you please.
Here's a very short video I did using my Windows Mobile phone propped up on a table in a coffee shop. It's nothing impressive, but including the filming it only took me about 10 minutes to make:
Another option: MakeAVI
While I heartily recommend Windows Movie Maker for its ease of use, it has one stifling limitation: The minimum 8 FPS frame rate. If you want a higher frame rate, I have a free tool to recommend: MakeAVI. You can download the latest version from this page. MakeAVI is a very basic program that does just one thing: Takes JPEG images (i.e. still photos) and turns them into an AVI video.
To use it, simply click on the Add Files button and select all of the photos you want to include in your movie. Then you can pick your frame rate by entering it in the Playback frame rate box in the lower right. To make your video, click on the Begin! button. You'll be allowed to name the video file and then you'll be prompted to choose a Compressor, which is the software that actually makes your video file. Things get a little tricky here, and your options will vary. You probably won't want to use the Full Frame option--this will make a very large file. If you have an MPEG-4 option like Xvid available I recommend you use it, because it can achieve very high compression (i.e. small file size) without sacrificing much quality. Otherwise, Microsoft Windows Media Video is a good choice.
Before clicking on OK, one thing to consider is how big your photos are. By default, MakeAVI will make a video with resolution (i.e. width and height in pixels) as large as your original photos. If you took the photos at a high megapixel setting--say, 3 or 4 megapixels or higher--your resulting video will be unnecessarily large. Some of the Compressors (the technical term is "codecs") give you an option to resize the resulting video, which I recommend using. If you chose the Windows Media Video codec, click on Configure... and on the Pre-procesing tab check the "Resize to" box and enter a smaller size--640x480 is a good choice. If you choose another Compressor, it may or may not have a resize option. If you took your photos with a webcam or camera phone, this will probably not be necessary.
Once you've chosen a Compressor and configured it, click on the OK button and MakeAVI will create your video file. The resulting file will probably be pretty large. From here I recommend importing the file into Windows Movie Maker and, as above, adding music or titles as you please and then using the Finish Movie/Publish to commands to create a video file that meets your needs.
Here's the video I made in MakeAVI using the same photos as my Windows Movie Maker video:
As you can see, it's basically identical to the first video, but moves about twice as fast since MakeAVI let me use a 15 FPS setting instead of Movie Maker's minimum of 8.
Published: Feb 21, 2008
Author: Jordan Running
Related OS: XP / Windows / Vista
Related Links:
http://sourceforge.net/projects/makeavi/
http://www.youtube.com/watch?v=-cdIRcBTjP4 - Corn Growing
Published: Feb 21, 2008
Author: Jordan Running
Related OS: XP / Windows / Vista
Related Links:
http://sourceforge.net/projects/makeavi/
http://www.youtube.com/watch?v=-cdIRcBTjP4 - Corn Growing
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