Aerial surveys

Aerial survey is a method of collecting geomatics or other imagery by using aeroplanes, helicopters, UAVs, balloons or other aerial methods. Typical types of data collected are aerial photography, LiDAR, remote sensing (using various visible and invisible bands of the electromagnetic spectrum, such as infrared, gamma, or ultraviolet) and also geophysical data (such as aeromagnetic surveys and gravity. It can also refer to the chart or map made by analysing a region from the air. Aerial survey should be distinguished from satellite imagery technologies because of its better resolution, quality and atmospheric conditions. Today, aerial survey is sometimes recognized as a synonym for aerophotogrammetry, part of photogrammetry where the camera is placed in the air. Measurements on aerial images are provided by photogrammetric technologies and methods.

Aerial surveys can provide information on many things not visible from the ground.

Azimith:- The clockwise horizontal angle measured about the ground Nadir point from the ground survey North meridian the plane of photograph.

Aerial surveys are used for:

Aerial survey uses a measuring camera where the elements of the interior orientation are known, but a camera that has much larger focal length and film and more lenses is used.

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