I have filmed most of the footage for a short film on 16:9. Can I 'trim' the small amount I have shot in 4:3 to match?

I'm using FCexpress.

A simple yes or no is all I need!

Does this do what you want?

http://www.dvinfo.net/conf/showpost.php?p=191584&postcount=12

I love this site! Cheers Boyd.

You're welcome! However I just realized you are probably using PAL and the instructions in that thread were for NTSC.

Try this instead: take the 4:3 clip and drop it into your 16:9 sequence. It will be pillarboxed with black bars to the left and right. Double-click on your clip in the timeline so it opens in the viewer. Now turn on "Image+Wireframe" using the pull-down [ ] button at the top of the viewer window.

"Grab" the dot in one of the corners with your mouse and pull outwards until the image zooms to fill the whole width of the window. Now you can point anywhere in the middle of the image and slide it up or down as desired to frame the 4:3 as 16:9.