Is The Sky Really The Limit For Vertical Aerial Photography?
Cartography, the process of producing maps is an ancient practice. In antithesis, the practice of photography is a relatively new concept. Putting the two together to produce vertical aerial photography is one of the latest ways of producing a true image of the earth's surface. We take a look at the applications of such technology and how these images are captured.
Looking down on the planet induces a sense of wonder and awe in most people. Familiar objects become strange shapes in a swathe of colour and perspective shifts to such a degree that we are often unsure of the context of the image. Roads lined with houses could easily be a macro shot of a circuit board. Rivers and estuaries look more like algal blooms captured up close. This is peculiar only to vertical aerial photography though, and here is why.
Vertical aerial photography is defined by a set of parameters that determine angle and therefore the perception of the image. Oblique aerial photography on the other hand produces recognisable images by varying the angle outside these parameters. The difference in angle in oblique aerial photography determines the amount of landscape in the image. The more oblique the angle, the more area is covered. This produces a large amount of distortion in a photograph so is rarely applied in areas where precision is paramount.
Vertical aerial photography however remains within an angle of three degrees which ensures that the image is as true to scale as universally as possible. This is achieved by ensuring that the principle point, which is the point of view from the lens, takes an image that cuts through the isocentre at a perpendicular angle to the nadir point, which is directly behind the image to be photographed.
These parameters ensure that scale and context is consistent in the image, which makes vertical aerial photography an ideal platform for use in mapping. When these images are joined together it is possible to produce a seamless map that could be used for surveying purposes. As well as being used for practical purposes, the images caught using vertical aerial photography have been used to compile an interactive map for a popular search engine company. These maps allow users to interact by adding photos of the area, bus routes and timetables and even snippets of tourist information. When internet technology meets with aerial photography, even the sky isn't be the limit when it comes to the future of cartography.
Looking down on the planet induces a sense of wonder and awe in most people. Familiar objects become strange shapes in a swathe of colour and perspective shifts to such a degree that we are often unsure of the context of the image. Roads lined with houses could easily be a macro shot of a circuit board. Rivers and estuaries look more like algal blooms captured up close. This is peculiar only to vertical aerial photography though, and here is why.
Vertical aerial photography is defined by a set of parameters that determine angle and therefore the perception of the image. Oblique aerial photography on the other hand produces recognisable images by varying the angle outside these parameters. The difference in angle in oblique aerial photography determines the amount of landscape in the image. The more oblique the angle, the more area is covered. This produces a large amount of distortion in a photograph so is rarely applied in areas where precision is paramount.
Vertical aerial photography however remains within an angle of three degrees which ensures that the image is as true to scale as universally as possible. This is achieved by ensuring that the principle point, which is the point of view from the lens, takes an image that cuts through the isocentre at a perpendicular angle to the nadir point, which is directly behind the image to be photographed.
These parameters ensure that scale and context is consistent in the image, which makes vertical aerial photography an ideal platform for use in mapping. When these images are joined together it is possible to produce a seamless map that could be used for surveying purposes. As well as being used for practical purposes, the images caught using vertical aerial photography have been used to compile an interactive map for a popular search engine company. These maps allow users to interact by adding photos of the area, bus routes and timetables and even snippets of tourist information. When internet technology meets with aerial photography, even the sky isn't be the limit when it comes to the future of cartography.
