Hi all, trying out our (not commercialized) invention set for the PH3P (but promised), I am for myself interested to produce graduated ones. I have no Phantom, only the Inspire. Trying out on the Ph3, I discovered a better global equal exposure when there is a heavy shining sky. This will result in a better dynamic range when recorded in flat. I am no fan of a polarizer for video and it will be too heavy, a balanced gimbal is a priority. Struggling for a while to make a choice as I can produce maximum 2 filters. Our factory is expensive for these ones. Questions: 1.applying a graduation on the whole filter or only on the half (more difficult to produce) ? 2.applying this extra layers on a full ND8, ND16 and or ND32 (only 2, this will result in producing 2 filters, otherwise too expensive) ? 3.the graduation from top to middle (or to bottom) starting from ND2, ND3 (exceptional grading) or ND4 to ND0 ? Applying a graduation on 50% is more significant as on 100% surface ! Concerning the leveling on horizon: as the thread on the camera is rather long, I wil screw to the end and go back for the right horizontal level, take a piece of scotch and fix it. Agreed not esthetic but practical and keep my weight at 3 gr (I refuse the others at 9,5 gram). Testing our set on the Phantom3 to keep gimbal motors cool is very important. So very interested for your opinions to make my decision clear for a production (even only for myself if too expensive to commercialize). I thank you very much. Factory will make 2 graduated filters for USD 48, double price of our normal ND's. Just make the right choices. Best regards, Renaat PS actually we are proud to have delivered >1.200 sets around the world (1% in Asia !) Lucky factory and lucky DHL and hopefully you too !