Hi Mike, I am Charles from Gibraltar, congratulation on the observatory, it's great. If you do not mind I would like to ask you a question. I have the same scope and my intention are to buy a similar cameraSXVR-H694 , I do have the Starlight AO, wheel & lodestar, my concern is the BFD, from the focuser to the chip, could you please tell me what distance did you achieve BFD, and from where exactly did you measure distance.....Charles