i've mentioned a few times that i got into aerial photography lately. not satisfied with the image quality of the small sensors on all-in-one drones or what a compact camera could do, i set out to gradually upgrade a three year old hexacopter to carry my d850.
other than some different kind of camera control in the future, i'm pretty much done with this setup. i have an idea for another copter i'm going to build based on a mix of these components, some from the graveyard of various crashes and some i'll buy/make.
here's the overall aircraft:
it's a few remaining pieces from the original DJI s900 (hardly any, lol) plus their e1200 propulsion kit, a reinforced top plate, custom extended landing gear legs, n3 flight controller, lb2 video link, third party gimbal, etc.
the camera is really why i built this guy rather than buying one of DJIs high end setups. i already have a d850/d810/d500 and a ton of lenses, so zero cost. short of medium format, it's the best still image quality you can get for this kind of shooting. i've shot with the 20 f/1.8, 28 f/1.8, 35 f/1.8, 50 f/1.8, and 85 f/1.8. it's very easy to switch between these lenses, just change lens and slide the camera forward or back a tiny bit, and get back in the air.
the radio and fpv solution is DJI's lightbridge 2. i did not like the loose antenna wires going up the legs, so i integrated an antenna kit from one of DJI's more recent drones, the M600. all this takes is two oblong holes in the legs plus two holes in the cap plate of the landing gear bracket, then you can route the two antenna inside the legs and into the frame. nice and clean, taking care to make sure the antenna wires don't get crimped when the legs fold up.
i don't like anything mounted on the top plate besides the gps, which i prefer to be in the very center.
the n3 flight controller is mounted dead center on top of the plate which covers the power distribution wires, not really visible here. i'm not totally thrilled about this since that plate is very thin, but it's not going anywhere.
the lb2 which is both up/down radio link is on a little standoff in the back center. it needed to be lifted up slightly to fit. this it the hardest thing to fit inside the frame because of the antenna connections and hdmi cable, but it works. the led is on a little aluminum l bracket attached to the underside of the top plate.
the shutter control is routed from an f port on the n3 (only one pin is used) through a spliced cable to the aux port on the aircraft side of the gremsy quick release. the gimbal then routes it internally, and then from a similar aux port on the camera plate. i needed a shutter control cable for this particular nikon remote port, a very old fashioned screw in connector. power is not supplied from the n3 f ports, so i spliced in the power from the gimbal itself. this is a weak point of the setup - all i get is "shoot," which focuses and then shoots.
the other weak point is the hdmi cable. the gimbal doesn't route the hdmi signal through the slip ring, so i used an ultra thin hdmi cable which just hangs loose. doesn't seem to have any effect on gimbal movement, but not pretty.
it flies fairly smoothly in both GPS and ATTI modes. the video image on the ipad connected to the LB2 remote is very high quality, 1080p or 720p, and the gimbal control from the remote is smooth and easy. the left back wheel controls the gimbal and can be switched from pan to tilt with the adjacent button.
with the tattu 22000 mah battery pictured, flight time to ±20% charge is 22 minutes fully loaded. with a tattu 12500, it's 14 min. i actually think the sweet spot might be somewhere in between there, and with a very slightly lighter camera. i might try a different camera with something like the maxamps 17000, which has an excellent power to weight ratio.
some concluding notes:
1. image quality is amazing. certainly better than anything flying short of a hasselblad on an m600 or a custom heavy lift rig.
2. fairly easy to fly other than the pucker factor of 10k USD worth of gear and approx 9.4kg of weight in the air.
3. camera control is rudimentary. i would LOVE to be able to easily move the focus point, or manually focus. i'm thinking about how to achieve that.
4. the only downside of gimbal control is that since i also use this for FPV and orientation, it's a bad idea to move the pan axis too much. i prefer to leave it in the direction i'm going, since there's no way to "know" which way it's facing relative to the nose of the aircraft.
5. the only thing that was at all hard to get working was the camera control. required a bit of custom wiring and testing.
6. the tattu 22000 mah batteries BARELY fit. initially they look like they don't fit, especially with the velcro straps, but they can be squeezed into place.
7. at some point DJI changed up the screw hole size in the props for the E1200. very, very, very annoying. i have some sets that required drilling out the holes, since the included screw wouldn't fit in the motors, and the original screw from the motor wouldn't fit through the props.
8. DJI service is absolutely abominably miserable. basic questions on their forum (e.g. the prop screws) remain unanswered. email exchanges take forever to get past irrelevant comments about firmware and so on.
9. if i was doing video, or did not already have a ton of nikon gear, this would not be worth it. i'd get an inspire2 and the x7 aps-c camera which is amazingly well integrated.
10. in the process of getting everything working, i had two fairly disastrous crashes. one an unexplained "return to home" which flew through a tree, and one when i didn't pay close attention to the settings on the n3, remote, and the different CSC of the LB2 and it flipped over on takeoff. made some really impressive 17" diameter holes in the ground tho!
