Hi CSR, welcome to the forums..
Yes this can be done, with a little out of the box thinking..
1. Locate the
Brightness and Contrast Filter and drag it to your clip
2. Click on
Customize.
3. Now on the first
KeyFrame (check the manual for explanation of keyframes), set the Brightness and Contrast to
-100, slide the sliders all the way to the left.
4. Move to a latter point in your clip, add a keyframe.
5. Set the Brightness and Contrast to about
-50. This would be about half faded in.
6. Move to a point latter, before the last keyframe, and add another keyframe.
7. Right click on the previous keyframe (one with -50) and select copy, then paste this to the keyframe you just created.
8. Go to the last keyframe and set the Brightness and Contrast to -100.
Now you should have a clip that fades in to half opacity, then fades out.