16:9 in Final Cut Pro
The mystery is solved when shooting in 16:9 and working in Final Cut Pro. In the old days, video production was simple. There was just one television format, and no-one had to worry about designing their production for a widescreen. Now, with the introduction to the 16x9 format, it can become confusing, especially when trying to mix the standard 4x3 format with 16x9 images.

Nothing is worse than walking into your local technology store and seeing a beautiful wide screen television with an image that is distorted. It defeats the entire purpose of purchasing a wide screen television. Worse yet, what if you want to shoot a project in true 16:9 but you want it to look correct on a standard television screen? Try explaining to someone that actual difference between a 16:9 image and a 4:3 image, and why it is distorted. That requires a lot of math, and often confuses people.
With Apple's Final Cut Pro, things have never been easier! The trick, is to shoot with a DV camera that has a firewire port. DV cameras record something extra along with the compressed video. The record time-stamp information and some additional meta-data that is embedded with the video. Final Cut Pro understands this information when you record directly from the DV port on a camera or tape machine. By shooting in a true 16x9 mode, if you were to play back your tape on a standard 4:3 television set, your image would look stretched.
Take a look at this example: You can clearly see that it looks slightly stretched out. This is how the clip would look if you recorded from a non-dv source, where Final Cut Pro is unable to interpret the meta-data.

If you right click (control click) on a clip and select 'item properties > format', A dialogue box will appear.

You will notice the anamorphic category setting is checked indicating a 16:9 video format. If you uncheck this selection, your video clip will become distorted as shown above.
