The Playfield is not the black mirror there is another sheet over the top which is used for video reflection and to make sure the balls don't hop out of the Playfield ( which they most certainly want to do ).
The tinted sheet is cut out to sit flat over everything , there is no physical connection , it can be removed with everything including the flipper bats in place - So no distortion issues.
As far as the sharpness of the inserts bear in mind this is being looked at from a single aspect via a camera.You'll notice the arrows are right triangles because of the camera distortion ( fish eye ) at the distances involved. This is just another unexpected thing I had to amend.
This whole thing is juggling act of lighting , focus , aspect , saturation, contrast and speed...a pain infact