Oblique and Nadir Aerial systems
A nadir image is an image captured vertically by a satellite. An Oblique and Nadir image is an aerial photograph collected at a corner of 40° to 50° downwards. The Nadir is the point vertically beneath the camera centre at the time of exposure. An oblique and nadir aerial system camera consists of optical sensors inclined to the vertical direction, simultaneously producing images from various viewpoints. When taking a photo, two different axes form from the middle of the camera eye, one towards the ground plane and the other towards the photo plane. The direction is called the vertical axis, while the pathway traced from the middle of the lens to the photographic axis is known as the photographic/optical axis. The two axes coincide with one another if the photo plane is held parallel to the ground plane. This photograph is considered a Nadir aerial view. The ability to use higher nadir images enhances the accessibility of a satellite, allowing a satellite to revisit a region quickly....