If I apply filters such as brightness, gamma and contrast to a shot in Final Cut, occasionally highlights get rendered as black. Please see the second shot in the video below (for a DVD menu) for an example. The light at the top of the frame is partially blacked out, at the brightest spot on the light. You can also see a speck of black on the smaller light to the right.

http://vimeo.com/10199874

In shots including a blown out sky, at times the entire sky become black once the shot is rendered. I've never seen anyone else mention this problem.

It only happens upon render, the shot itself with filters applied but unrendered looks fine. It doesn't always happen, and I can't find any pattern in relation to which of the above filters I've applied or to what parameters I've set within them.

Any help would be much appreciated.