Why doesn't video capture work on my Mac?

There can be several reasons for video capture to fail. A few possible reasons are these:

1) Make sure you have Logger Pro 3.4 or newer installed. Video capture did not exist in previous versions.

2) You have no working driver installed for your web camera. Some web cameras will work with OS X, but the manufacturer just does not supply the needed drivers. The driver available at http://www.ioxperts.com/ will often make a camera work. Note that the driver costs $19.95.

3) There may be a conflict between two drivers. In particular, the driver from Logitech or IOExperts will fail if the driver for the ProScope is installed. The Proscope driver is located in the following folder:
/Library/Components/Scalar USB Microscope.component

This driver will prevent the Logitech or IOExperts drivers from working. Move "Scalar USB Microscope.component" to a different folder to use the Logitech or IOExperts device drivers. No reboot is required.

In any case, begin troubleshooting video issues by running the software supplied with your camera. If that software cannot function, Logger Pro will not be able to use the camera.