I recently purchased an SBIG 16803, with FW7-STX filter wheel and STX Autoguider. To go with it I bought the Astronomik 50mm square filters.....LRGB Ha, OII & SII. I carefully followed the supplied instructions for their installation. As an aside, the instructions say to remove one screw and swing the sensor out of the way so as not to damage it. The computer card design has however, been changed such that it is wider where the sensor is to be swung out of the way. Therefore it is no longer possible to do this. The instructions need to be updated to reflect that. I ended up removing both screws and carefully lifted the entire sensor out of the way. In any case, per the instructions I careful slid the filters around the carousel into their positions. The instructions then say: "Attach the press plate and tighten it down enough that all filters are held in place, but not so much that you risk cracking a filter. Only light pressure is needed to prevent the glass from rattling. They do not need to be clamped tightly." I did this, however there did not seem to be any mechanism for retaining the filters rigidly in place. Sure enough after assembly I could hear them rattling around when I moved the camera. I disassembled the FW and redid the steps to make sure I had done it properly. I tightened the press plate as far as it would go and it seemed clear to me it was making no contact whatsoever with the filters. Again they are still rattling around when I move the camera. Surely this is not right. I would have thought the press plate should have a rubber gasket around the outside of each square hole to mate against the filters to hold them in place. Please advise.