1) Safety & Regulations
As a drone pilot you are responsible for a small aircraft that has the potential to do damage or harm others. You have to operate safely and adhere to the existing regulations.
Things to Think About
The regulations for recreational drone flights are contained within the Air Navigation Order 2016 (ANO) which is the primary document for all aviation regulations within the UK. In order to keep the regulations at a proportionate level for these small drones, a set of specific, simpler, regulations apply to aircraft that have a mass of 20kg or less (which are termed ‘small unmanned aircraft’ within the ANO).
In simple terms, these regulations state that:
- you are responsible for flying your drone in a safe manner
- you must keep the drone in your direct sight at all times while it is flying, so that you can ensure that it does not collide with anything, especially other aircraft
- you must not endanger anyone, or any thing with your drone, including any articles that you drop from it
- if your drone weighs more than 7kg, additional rules apply if you fly in certain types of airspace and you must not fly above 400ft above the surface
- If your drone is fitted with a camera, there are also a number of additional limitations surrounding where you can fly it, and how close you can fly it to other uninvolved people or objects. In order to be able to fly within these areas, or closer than the minimum distances that are in the regulations, you must obtain prior Permission from the CAA to do so.
The full regulations are shown below.
First Person View
Drones that are fitted with video cameras often provide an opportunity to downlink ‘live’ video to the person flying the drone either via a mobile phone, tablet computer or other screen, or even through video goggles - this capability provides the operator with a pseudo ‘pilots eye view’ from the drone itself and is generally given the term ‘First Person view’ (FPV).
However, the law [at ANO article 94(3)] requires that the person in charge of a drone must maintain direct unaided visual contact with the aircraft which is sufficient to monitor its flight path so that collisions may be avoided. This is obviously not possible if that person is wearing video goggles or otherwise constantly monitoring a display. Therefore, FPV flight is only permitted if the activity has been approved by the CAA. A General Exemption has been issued which allows an element of ‘First Person View’ (FPV) flight to be conducted.
Guidance on the exemption and the conditions that must be observed whilst employing this privilege.
If you wish to conduct an FPV flight which cannot be accommodated within the terms of this General Exemption, then you will need to apply to the CAA for an exemption to do so.
Note: Images captured by a camera and displayed on a flat screen afford the pilot little by way of depth perception and no peripheral vision. This can make it difficult for the pilot to accurately judge speed and distance and to maintain sufficient awareness of the area surrounding the aircraft to effectively ‘see and avoid’ obstacles and other aircraft.
The use of FPV equipment is not an acceptable mitigation for Beyond Visual Line of Sight flight unless the relevant operator has received a specific approval to do so from the CAA.
The regulations make no distinction between flights made indoors or in the open; the whole safety criteria continue to apply. Notwithstanding this, certain hazard factors are heavily mitigated by the fact that the aircraft is flying in an enclosed environment and access to the venue can be controlled. People within the building, and who may be exposed to a hazard by the flight, should meet the criteria for ‘persons under the control of the person in charge of the aircraft’ or else have safety precautions taken on their account (e.g. safety netting, tethered drone, etc).
Minor indoor recreational use of a very small and light ‘toy’ drones is not generally regarded as having the same safety implications as for larger drones used outdoors.
Long-exposure shots are relatively easy to take at night with a DJI drone since their cameras are stabilized. Just set a low shutter speed and press the shutter button. If you are capturing cars, boats, or any other illuminated objects moving at night, you will end up with some cool light trails like in the picture below. But if you’ve tried taking a long-exposure shot during the day, you know that once you’ve set the smallest aperture and lowest ISO possible, increasing your shutter speed will inevitably overexpose your shot. This is where ND filters come in handy.
What is an ND Filter?
A Neutral-Density Filter, or ND filter, reduces the amount of light that enters a camera’s lens. Under bright sunlight, an ND filter allows photographers more leeway in selecting an aperture and shutter speed by preventing overexposure.
In addition to using ND filters for daytime water photography, they can also be used to take better urban landscape shots.
The shot below was taken with a relatively fast shutter speed. It looks a bit stiff and unnatural. The cars and people are moving, but there’s very little motion blur.
With an ND filter, we can lengthen the shutter speed and create some motion blur. Motion blur can give your photos a more lively and active feel, like the one below.
As you can see, by gaining more lenience to adjust your shutter speed, ND filters give you more creative control over your shots.
Choosing ND Filters
DJI has three official ND filters for their drones: ND4, ND8, and ND16. The number associated with an ND filter indicates that how much light enters the lens in terms of a fraction.
- ND4 reduces light by 1/4. An ND4 filter can reduce 2 stops of light, allowing you to slow the shutter speed from 1/100s to 1/25s.
- ND8 reduces light by 1/8. An ND8 filter can reduce 3 stops of light, allowing you to slow the shutter speed from 1/200s to 1/25s.
- ND16 reduces light by 1/16. An ND16 filter can reduce 4 stops of light, allowing you to slow the shutter speed from 1/400s to 1/25s.
Take the Phantom 4 Pro as an example. The screenshot below was taken without an ND filter and an ISO of 100, an aperture of F2.8, and a shutter speed of 1/200 seconds.
HDR stands for “high dynamic range." In simple terms, dynamic range is just the difference between the lightest light and darkest dark you can capture in a photo. Once your subject exceeds the camera’s dynamic range, the highlights tend to wash out to white, or the darks simply become big black blobs. With modern shooting techniques and advanced post-processing software, photographers have devised ways to capture and manipulate colour. In summary, HDR is a specific style of photograhy with an unusually high dynamic range that that is achieved by creating a single image by combining multiple of exposures (Both over and Under).