Only way to equip the camera with a filter unit, the unit is compact enough: we must set a tube (with screws) on the nose of the aircraft, which becomes permanent; only then attach over the filter or a second tube. The next problem is the zoom power: you have to zoom all the time for the image to be 'full size' (otherwise the image integrates the tube, and the subject thus appears surrounded by a black circle = > must constantly remove or replace the second tube and the filter of what we want to do. It just spoils the pleasure of doing unasked pictures
