I guess that would be possible, but one has to do some trickery to find false data. Maybe correlating the exact oposite dip works: Dipping a bowl shows a negat

I guess that would be possible, but one has to do some trickery to find false data. Maybe correlating the exact oposite dip works: Dipping a bowl shows a negative volume then the bowl begins to fill. A dome (reversed bowl) will show additional volume of trapped air at the same point.