A few months ago I mentioned about Taking Time Lapsed Screen Shots With Terminal, it was a script which would take a screen shot every couple of seconds of your desktop. This is useful if you are taking a time lapse movie, but it is not useful if you actually want to show people videos of your desktop. I have previously written a post on iShowU which can take movies of you desktop. This post will show you how you can do this for free using QuickTime Player which comes with Snow Leopard.
To capture your desktop video open QuickTime Player in your Applications folder. Then from your File menu select “New Screen Recording”. This will open up a little widget with a record button as shown in the image below. From the down arrow you can select a couple of options, first the sound input. If you want to select your audio which your computer makes you can either use a Male to Male cable and plug it in your input and output on your Mac or you can download and install SoundFlower, which allows you to pass audio into QuickTime. Other options from the flippy down arrow include the quality and the save location.
When you are ready you can start recording. Press the little red record button and it will start recording what ever is on your screen. When you have finished recording press the stop button in your Menu Bar.
Once as you press stop QuickTime will do a little bit of processing and your video will be available to view. Note that it will record at what ever your screen resolution is set to, as a result it will more than likely produce a large HD video, which is really good for playing back but not that useful if you want to share with your friends. So its worth trimming the video before you compress it, this way you have the least amount of video to compress. To trim the video go to Edit > Trim and cut out the beginning and end of the video to what you want. Every bit you cut off is less you have to compress down the line making the final video file smaller.
When you have trimmed your video you can now save it for final use, although the final video is already saved in your Movies folder (or other location if you specified it) its worth compressing the video. Go to File > Save As or File > Save For Web. The former is good for saving for use on your computer, since you can select 480p resolution, among a variety of others. The latter is good if you plan on putting it on the web. Have a look at the settings and pick on which you think is suitable for you. If you want more options it may be worth opening the movie in the older version of QuickTime and using that apps options.
There you have it. Capturing your desktop as a video couldn’t be simpler. If you want to learn more about QuickTime I recommend Mac OS X Snow Leopard: The Missing Manual or Apple Pro Training Series: QuickTime Pro. There are many resources out there so look around.