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DJI QUAD COPTER AND GOPRO CAMERA
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WE NEED YOUR SUPPORT. |
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A Different Point of View.
Over the years we have taken thousands of photographs and almost without exception they have been the sort of shots that anyone could take.
New developments in technology have meant that we were able to purchase equipment that allowed us to start taking photographs from an entirely new perspective.
The merging of remote controlled quad-copters with small and extremely powerful cameras has put into ordinary people's hands, the sort of technology that was once the purview of major film studios.
The technology is rapidly changing and although we only got our system in late 2013, it is already out of date with new models making it much simpler to acquire a package that took us some time to put together and assemble.
The quad-copter we are using is a first generation DJI Phantom. I have never flown any remote controlled aircraft before but I was amazed at how easy it was to fly. I will never really develop great flying skills as I am sight impaired, so I am not about to try to fly the Phantom in anything but up, down and in straight lines.
The great thing about these smart toys, is that they have a built in GPS that allows a 'return to base' function in an emergency. I have used this a few times and it has proven to be invaluable when the Phantom gets too far away and I am no longer able to work out which way it is flying.
The first generation Phantoms have fairly limited flying time. This works out to be around 8 minutes when the copter has a gimbal and camera attached. It may not seem like much, but for our purposes, getting more interesting still shots, it is more than enough.
The gimbal we use is a DJI Zenmuse and it produces great results in even quite strong winds. A gimbal is simply and electronic arm that holds the camera level when the Phantom moves about in the wind or tilts as you fly it. We had tried to get photos without a gimbal but the results were disappointing.
The gimbal did involve some hands-on installation and soldering. I am pretty much an idiot when it comes to these things but I followed an instructional video on the internet that showed how to do the install. It took me a great deal longer than the estimated time given on the video but at least everything was working when I finished. The point of this is, 'if I can do this, anyone can'.
The third critical part of this package is a GoPro Hero3 black edition. This is simply an amazing little camera. Small and light-weight it is easily carried by the Phantom and it has all sorts of useful shooting modes. The main way we use the GoPro is to shoot video and stills shots at the same time.
The GoPro has a very wide angle lens that does produce a 'fish-eye' effect when used at the widest setting but there is software that will help to reduce the effect or you can choose a more narrow field of view.
By the time we had finished putting this equipment together we had spend something in excess of $2000 but the results we are getting make this investment worth while.
We still have one more component to add that will make getting exactly the right shots easier. Known as FPV or 'first person view' it will allow us to see exactly what the GoPro sees while it is shooting in the air.
As I am neither a professional photographer or an experienced remote controlled aircraft operator, I have to admit that I am very surprised at how good the results we have got so far have been. This owes a great deal more to the clever technology than anything I contribute and it means that anyone who is interested in getting into this particular way of filming can do so with ease.
The main area of concern is having some sort of accident with the Phantom that will wipe out the investment in mere seconds. We have already had a couple of accidents. The first involved a sudden fierce gust of wind and a large (tall) pine tree.
The Phantom is designed to hover in place when set in GPS mode BUT its ability to get back to the point it has been instructed to hover at, involves a short time lag of 2-3 seconds. This may not sound like much but when the Phantom is hit by a sudden gust of wind and pushed off its hover point, it needs to be more than 3 seconds away from nearby structures. In our case the structure was a very tall pine tree in the top of which, the Phantom got firmly lodged. Thankfully a helpful young man from the local Fisheries Department offered to go up the tree and try to the the Phantom back and he was successful.
The second accident happened when I neglected to keep an eye on the time I had been flying and the Phantom, detecting low battery, decided it was time to land before it ran out of power and the place it chose to land was on top of a mangrove bush. This meant that the controls became unresponsive and the Phantom landed in a place that was a bit awkward to retrieve it from. Luckily I had a ladder on hand and was able to get the 'bird' back safely.
The thing that scares me most when flying, is any body of water. If the Phantom goes down in water then the whole setup will be a write off. We do have 2 Water Bouys attached so that the Phantom will at least float back to the surface but the electronics would all be fried.
Some notes about batteries for the Phantom
Because flight time on one battery is limited to about 8 minutes, it is necessary to have several batteries. We have 8 at the moment. Having a number of batteries means that the standard 1 battery charger that comes with the Phantom is completely insufficient so to make charging faster we purchased a multiple battery charger.
We didn't want to 'break the bank' so we got one from Hobby King and so far it has worked well. The charger works from a 12 volt source which is ideal for filming away from mains power.
We had been very familiar with lead acid, AGM and Gel Cell batteries but the LiPo (or lithium polymer) batteries that are used to power the DJI Phantom were something very new and unexpected.
Normal batteries are very happy when they are fully charged and left that way. LiPo batteries are not at all happy to be left fully charged for long periods of time and need to be put into what is called 'storage mode'. This means getting the battery down to about 11.4 volts and the charger shown above has this as one of its functions.
LiPo batteries are VERY VOLATILE and must be handled with great care. If punctured, charged incorrectly or just too old and charged too often, they can, and do explode rather violently. They have been responsible for a number of fires so it is vital to store them properly, charge them properly and to carry them in a fire proof or fire resistant container.
Our recommendations for flying a Phantom.
1. Always allow the Phantom to go through its pre-flight checks completely. Do not try to fly the machine before it is showing all green lights.
Other things that might be useful to know
1. Balance charge your batteries regularly to make sure they are in good condition.
FPV (First Person View)
FPV is a method of seeing what the camera on the Phantom sees while you are down on the ground. Since installing this system the pictures we are getting from the Phantom/GoPro combo are so much better. The flying experience is also better as it is possible to fly off in different directions and still find your way back.
The following items were what we ordered :
Fat Shark Dominator Goggles
To connect these up you have to do a bit of soldering and there are NO instructions that come with the items that explain which wires connect to each other.
Basically the ImmersionRC transmitter (Tx) is the heart of the system on the Phantom. You need to get a plug to connect to power coming from the Phantom. We used the aux power wire that the Phantom has just poking out near the top of one of the legs.
You ignore the audio wires coming from the transmitter - in fact you can cut them off. Run power from the Phanton to power input on the transmitter, wire the video out line on the transmitter to the central pole of a male RCA plug (you will need to get one separately) and wire the 5v GND on the transmitter to BOTH the outer connection on the RCA plug and to the black cable from the CCD camera. Run the 5v power out from the transmitter to the red cable of the CCD camera.
Apart from fitting the receiver (Rx) into the Fat Shark goggles and attaching an aerial to both the goggles and the transmitter there is not much else to do but use some velcro and zip ties to make everything neat.
The CCD camera we got comes with a small mounting and we screwed that directly into the middle of the Phantom's battery door, making sure to pad the inside to avoid damage to any cables.
It would be possible to leave out the CCD camera and get vision directly from the GoPro but we decided it would be best to get vision from a separate camera that correctly shows the orientation of the Phantom while in flight. (eventually we decided this was not needed and now just use the GoPro.)
The FPV system turned out to be excellent. For someone like me who has pretty bad eyesight this opens up a whole new way of using the Phantom. Trying to fly it from the ground was very difficult once it got more than a couple of hundred yard away. I had no way of knowing which direction the Phantom was pointed but now, as long as I keep track of where the Phantom is in relation to myself, I can fly it properly and turn in any direction I like.
During the first test we made use of the CCD camera but since then we have received a cable to connect the ImmersionRC direct to the GoPro. This reduces weight a bit and means that while flying I can see exactly what the camera sees. This is useful when the camera angle needs to be adjusted.
Problems in Flight
1. Lack of control
Most of the time the Phantom flies well and does (more or less) what it is told to do. Sometimes, however, it misbehaves and does not respond well to commands from the transmitter.
This is the primary reason you MUST do the 'compass dance' each time you fly in a new location and allow the pre-flight checks to complete so that you have all green lights before you fly.
On about three occasions we have had to rely on the 'return to home' emergency function built in to the Phantom. This involves turning off the transmitter so that the Phantom recognises loss of signal and returns to the point it took off from.
This has worked well to date as each time it has flown back and I have simply turned the transmitter back on to regain manual control.
2. Low battery
Another problem has been caused by not keeping track of how long I have been flying. This has meant the Phantom has detected low power and decided it is time to land. If this happens there is NOTHING you can do to stop it from landing. On one occasion this caused it to land on top of a mangrove bush and I had to retrieve it.
To resolve this problem I have attached a small digital timer to the transmitter and set it for 5 minutes. Once the beeper goes off I know I have about 60 seconds to bring the Phantom down safely.
3. Wind
In GPS mode the Phantom is supposed to hover in one spot even if you are not touching the controls on the transmitter. The only problems is a sudden gust of wind. It takes a couple of seconds for the 'brain' of the Phantom to realise it has been moved out of position and in that time it can be blown quite a reasonable distance.
If the Phantom is close to trees or other objects this can result in a crash. Be careful how close you get to structures if conditions are windy.
4. Sinking
We have noticed that at low altitude the Phantom starts to lose height even if it is in GPS mode. There seems to be no problem at higher altitude but it will gradually drop towards the ground when at low altitude.
So far we haven't worked out why this happens but just keeping a close eye on it prevents any problems.
5. Bird strikes
So far we have had no problems with this ourselves but have seen enough videos of this problem to know that the Phantom can be knocked out of the sky by angry birds.
Beware of magpies in nesting season and birds of prey at any time.
See some of the pics we have taken with the Phantom and GoPro.
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