In general, techniques are described for encoding static video data using a baseline video encoder. A first device moves the rear edge of the panel towards a raised position relative to the closed position and above the adjoining roof part. The combined light of the first transmitted test beam and the reference beam is analyzed by a first pair of polarization analyzers, and interference created between the first transmitted test beam and the reference beam as analyzed by the first pair of analyzers is detected to derive intensity, phase and polarization of the first transmitted test beam. In one preferred embodiment, a mounting apparatus is interconnectable with the magnet.