Black Bars in FCP 7 but still have control over image?

[Mark Suszko]

Make your bars manually on another video track above the actual video. Then you can independently adjust everything and even keyframe changes, like pan-and-scan type moves.

[Nick Meyers]

i generally drop the 2.35 mask onto a white clip,
export a frame,
then use that as a guide to make up a mask in Photoshop.

another approach is to lay 2 lots of slug onto tracks above your video, then move them into place.
still, i prefer to use the 2.35 as a guide
if you then un-enable one of the underlying clips, you can do an “Export Using Quicktime Conversion” from the that point in the timeline,
export as a still image, TIFF, and you can then use that TIFF file as a single track mask in FCP

nick