A recent question in the macosxhints forums, and some similar posts in Apple forums, sent me in search of a Photo Booth solution. It turned out to take only a small tweak to one Quartz composition inside the Photo Booth application package to produce unmirrored movies. Note that to edit the Quartz composition, you'll need Xcode installed.
- Make a backup of Photo Booth so that you can return easily to the application's original behavior if desired.
- Control-click on the Photo Booth application, pick Show Package Contents from the pop-up menu, then navigate into the Contents » Resources folder. Double-click on Effect.qtz within that folder to open it in Quartz Composer.
- Locate the left-most Flip patch. Select it and click the Patch Parameters gear.
- Uncheck the 'Flip' box.
- Save Effect.qtz and quit Quartz Composer.

