Close range aerials can be obtained in a wide variety of wind, weather and lighting conditions with the quality of the final footage being directly proportional to the severity of the conditions present. Obviously the best results will most often be achieved in near perfect conditions. The problem here is that we must work around mother natures schedule and not the reverse. Whether or not acceptable results can be obtained when the conditions are less than ideal is primarily dictated by the type and quality of platform employed, camera gimbal stabilization and the flying skills of the operator.
Wind
At present, most outdoor Helicam demo reel footage of acceptable quality will almost always have been shot with little or no wind present. For a single rotor platform, when significant winds are present, the best footage is usually obtained flying head on into the wind verses perpendicular to it for example. The winds direction is always an important consideration when planning each shot, for not only shot quality, but also approach planning in case an autorotation is required in the event of an emergency. Autorotation is the unique ability of a single rotor helicopter to maneuver and land without power. To consistently acquire usable footage in winds above 10 mph at this point in time, a large single rotor aircraft weighing at least 30 lbs. fully fitted with camera and other needed accouterments is required. In addition to needing this larger mass for overall stability, a well-tuned, gyro-stabilized camera gimbal is also required. The associated cost, complexity and skill required to fly and maintain these larger aircraft quickly narrows down the number of potential sources however.
Precipitation
If properly designed and installed components are used, it is not an issue to perform flight operations in light mist, rain and snow. Since the camera/platform is usually required at some point to engage in forward flight, precipitation typically becomes more of an issue of keeping moisture off the camera lens than creating an operational problem for the aircraft and/or operator.
Lighting
The quality of lighting (brightness) and overall visibility (lack of fog/haze) present has a direct bearing on the range or distance the helicopter can safely be flown from the pilot via "line of sight" during daylight operations. The position of the sun relative to the pilots viewpoint must also always be considered when laying out each shot. The aircraft must never be flown in a path that requires the pilot to look directly into the sun if possible. Shadows are another important consideration when shots are obtained from an aerial view. Things always look a bit different from above and shadows can quickly creep in a ruin an otherwise good take. In many cases there is ample time in a given day to film a large number of shots but the optimum window of opportunity for best lighting for each individual location is often very brief. Because of this, proper shot scheduling/planning for the lighting conditions is critical.
Flight operations during dusk, dawn and dark conditions are also possible using high intensity LED lighting systems on the aircraft. The range of operations using such lighting systems is very similar to that of daylight operations. The flight path must be carefully scoped out during the day in order to prevent collision with objects extending upward such as power lines and structures. Just as the suns position must be accounted for during daylight operations, the position of bright lights must also be taken into consideration during nighttime operations.
Dust and Dirt
A helicopter is a precision flying machine and so dust and dirt are its enemy. There are several techniques that are available to mitigate this type of issue however when the location requires operation in sandy, dirty or dusty environments. In such conditions, the rotor downwash from the helicopters blades will kick up large amounts of particulate, which, if not abated, which will find its way to the cameras lens, not to mention many of the close tolerance mechanical parts of the machine.
To summarize, it is possible to obtain close range aerial footage that will mesh with the look and feel of the particular scene in question, provided certain considerations and plans are made to account for the various environmental conditions at hand at the time of shooting.
For more info please visit http://www.perfectperspectivesaerial.com
Sunday, February 13, 2011
Saturday, February 5, 2011
Advanced Helicam Aerial Cinematography
Most Helicam aerial imaging is performed within a framework known as "line of sight" or LOS. There are several reasons for this. The most obvious being that if the pilot has a clear, continuous visual link to the aircraft being flown, it can be controlled at all times. The up side of this arrangement lies in its simplicity. Aside from flying behind an obstacle, having sudden vision problems or flying so far away as to lose orientation, there is very little that can go wrong, (aside from aircraft mechanical/electronic control problems anyway). The down side of this arrangement is that it limits the range of use to an area extending about 1200 feet horizontally and 400 feet vertically from the pilots fixed position. For the majority of shots required, this is a non-issue.
The radio control systems used today are capable of transmitting a clear signal several times further than the LOS distance. The position of the pilot is also critical for optimum LOS shooting. In some cases it is most effective to place the pilot on top of a building, mobile manlift or other fixed structure to improve visual range over any obstacles. This is particularly useful for flying just above tree-top level - skimming over a dense forest where trees would obstruct the pilots view if shot from ground level.
Helicams can also be piloted directly from the cameras transmitted video signal in what is called "first person view" or FPV. While this can improve close maneuvering around obstacles and extend operational range, loss of video feed remains a significant additional risk factor however. While this may be an acceptable risk for low end equipment, with the equipment currently available, it is not recommeded to fly a $50K to $100K camera kit using this method.
Recent advances in GPS based autopilots show great promise for extending the range of use well beyond the visual LOS range noted. These devices can be programmed in a manner that allows the aircraft to fly a series of "waypoints" and then return to its home position with just the flip of a switch. While this type of technology will assuredly advance the capabilities of Helicam systems for engineering and aerial mapping, for the moment there are several major technological hurdles that must be overcome first. Most notably among such obstacles includes the requirement of the system to sense and avoid both full sized aircraft and ground based obstacles. Another limiting factor is a pilot is capable of executing extremely complex, continuously variable commands that, at present, are well beyond the current capabilities of programmed systems.
As mentioned previously, Helicams are very well suited for operation from many types of moving platforms and vehicles in order to extend range. When land based vehicles are used for this purpose on public roads, local authorities should always be retained to temporarily shut down traffic and provide an escort if required in order to safely acquire the shot. Due to privacy concerns, state and local governments are also passing laws limiting or outright banning use of remotely piloted aircraft. Make sure to check local ordinances when scouting out aerial filming locations.
Another viable technique lies in the use of two or more pilots wherein one pilot hands off control to another in what is known as "relay mode". This effectively doubles the range of operation compared to single pilot operation and can be performed in a very seamless manner through radio communication.
At present, line of sight operation remains the predominant mode of operations for close range aerial imaging due to its inherent simplicity, flexibility and reliability. This will most certainly be augmented in the future in ways that are hard to imagine now.
For more info please visit http://www.perfectperspectivesaerial.com
The radio control systems used today are capable of transmitting a clear signal several times further than the LOS distance. The position of the pilot is also critical for optimum LOS shooting. In some cases it is most effective to place the pilot on top of a building, mobile manlift or other fixed structure to improve visual range over any obstacles. This is particularly useful for flying just above tree-top level - skimming over a dense forest where trees would obstruct the pilots view if shot from ground level.
Helicams can also be piloted directly from the cameras transmitted video signal in what is called "first person view" or FPV. While this can improve close maneuvering around obstacles and extend operational range, loss of video feed remains a significant additional risk factor however. While this may be an acceptable risk for low end equipment, with the equipment currently available, it is not recommeded to fly a $50K to $100K camera kit using this method.
Recent advances in GPS based autopilots show great promise for extending the range of use well beyond the visual LOS range noted. These devices can be programmed in a manner that allows the aircraft to fly a series of "waypoints" and then return to its home position with just the flip of a switch. While this type of technology will assuredly advance the capabilities of Helicam systems for engineering and aerial mapping, for the moment there are several major technological hurdles that must be overcome first. Most notably among such obstacles includes the requirement of the system to sense and avoid both full sized aircraft and ground based obstacles. Another limiting factor is a pilot is capable of executing extremely complex, continuously variable commands that, at present, are well beyond the current capabilities of programmed systems.
As mentioned previously, Helicams are very well suited for operation from many types of moving platforms and vehicles in order to extend range. When land based vehicles are used for this purpose on public roads, local authorities should always be retained to temporarily shut down traffic and provide an escort if required in order to safely acquire the shot. Due to privacy concerns, state and local governments are also passing laws limiting or outright banning use of remotely piloted aircraft. Make sure to check local ordinances when scouting out aerial filming locations.
Another viable technique lies in the use of two or more pilots wherein one pilot hands off control to another in what is known as "relay mode". This effectively doubles the range of operation compared to single pilot operation and can be performed in a very seamless manner through radio communication.
At present, line of sight operation remains the predominant mode of operations for close range aerial imaging due to its inherent simplicity, flexibility and reliability. This will most certainly be augmented in the future in ways that are hard to imagine now.
For more info please visit http://www.perfectperspectivesaerial.com
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