Which digital video camera should I purchase for video analysis?

There are two general classes of cameras we recommend for video analysis, and two that we do not generally recommend.

Good:
1) DV camcorders can yield very good images, and can capture live to Logger Pro synchronized with data collection. However, fewer and fewer DV cameras have firewire ports.
2) Digital still cameras are probably the best bet, but the video must be manually synchronized with data because they do not stream video.

Not so good:
3)USB web cameras almost always too slow in both shutter speed and in frame rate. We do not recommend their use at this time.
4)Flip-style cameras are another alternative. A few produce useable videos, but most suffer from two disqualifying flaws: either the videos produced use a proprietary codec that QuickTime cannot read, or the rolling shutter video capture creates unacceptable time smear across a single frame.

More details:

1) Digital Video (DV) Cameras - It is difficult for us to recommend cameras because the manufacturers are continually updating their product lines. For video analysis you need a consumer-grade DV or miniDV camera sold by brand name manufacturers, e.g. Sony, Canon, Panasonic, etc. These cameras typically cost $200 to $300. Get a camera that allows you to manually set the shutter speed to least 1/500 second. Some cameras are too automatic and don't allow you to set the shutter speed. You need to set the shutter speed so that fast moving objects aren't blurred on individual frames. If the camera does not allow you to set the shutter speed, look at a camera that has a "sports" mode. That mode has a fast shutter speed. It is also helpful to have a camera that has manual focus capabilities.

There are two common ways to transfer video to your computer: video stream, and as a file. If you use streaming video, the camera must have a firewire (aka i.Link) port, or a USB 2.0 port that functions as a video stream source. Firewire is more reliable.

If the camera creates files, they must be QuickTime-compatible. Usually a camera that creates "avi" file or a "mov" file can be used, but only a test will determine compatibility.

Many video cameras on the market have features that do not lend themselves to video work in the classroom. Quite often video cameras that record to optical disk DVD, or that record to MPEG-1 format, or record to a hard drive do not work well in this application. Unfortunately they often use compress series of frames and you lose important detail. This problem can also occur with HD cameras.

2) Still Digital Cameras - Most still digital cameras have a movie mode. These cameras can work very well. Look for a camera that lets you specify the shutter speed in addition to frame rate. Sometimes the shutter speed setting is concealed by a "sports" mode setting. In any case, you will need lots of light to force the camera to use a fast shutter. Outdoors is much better than even dual 250 W flood lights.

Until recently high speed cameras were extremely expensive, i.e. on the order of thousands of dollars. Recently Casio started to manufacture a line of still digital cameras that have a high speed video mode. Casio high speed offerings can be found here:
http://www.casio.com/products/Digital_Cameras/High-Speed/

This is a good option for physics since it allows you to analyze fast motion, e.g. swing of a baseball bat.

Again, still cameras with movie mode do not stream video, but will create files for transfer to your computer.

And a final note:
It's very important to test a camera with your computer and Logger Pro to be sure that the file format is compatible with Quicktime, and that you can install the necessary drivers for your camera. (This is generally only a concern with Windows.) We do not recommend buying a camera without first testing it or a very similar model.
Unfortunately the things that make a camera useful as a consumer product are quite different from the very specific needs for video analysis. This means that cameras must be selected carefully, and should be well tested before a large purchase.

To gather user feedback on cameras that have worked well, we've set up a forum topic:
http://www.vernier.com/discussion/index.php/topic,1356.0.html