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. This helps satellites respond more rapidly to incidents like earthquakes, hurricanes, or other natural disasters.
 

Oblique and Nadir Ariel System advantages:
The image scale produced is primarily constant. A Nadir aerial image (if grids and marginal details are added) can be used as a map.

Nadir pictures are always smoother than oblique images.
They give a pictorial view of landscapes.

They are used for geospatial planning
Due to a fixed camera height, a wide area of a single picture can be covered.
 

Conclusion:
An Oblique and Nadir ariel system is a powerful instrument for surveillance and tracking. It provides a valuable way to control the environmental risk of hazardous and inaccessible areas and to improve the geo-technical understanding of spatially complex la