If you want a high resolution reflective image, this is how to do it.
1) Rotate your camera 180 degree to film your character facing the mirror
2) Use the IMAGE overlay to represent the Mirror frame and place in front of character
3) Render scene as single uncompressed TGA Frames, i.e. frame001, frame002 etc...
4) Use photoshop batch system to flip every frame horizontally and generate a non compressed Video
5) Load new Video as Background Video Layer to your original scene ...
:D
See my Pinhead Movie of 2 years ago ...It uses such a scene...
Cheers!
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