I often get questions regarding these topics:
Oblique Aerial Photo
Photographs taken at an angle, out the window of the aircraft, are called oblique photographs. If they are taken from a low angle earth surface–aircraft, they are called low oblique and photographs taken from a high angle are called high or steep oblique. With an oblique photo, you have the opportunity to see the details of the property -- such as the front of a structure. The image also trails off into the distance allowing some perspective regarding the surrounds of a subject.
Vertical photographs are taken straight down, and the resulting image has a map-like view. These photos are typically used to emphasize the physical footprint of the property, because you shouldn't be able to see the sides of any of the structures.
Combinations
Aerial photographs are often combined. Depending on their purpose it can be done in several ways, of which a few are listed below.
- Panoramas can be made by stitching several photographs taken with one hand held camera. The "stitching" is completed via a computer-based photo program, such as PhotoShop.
- In pictometry five rigidly mounted cameras provide one vertical and four low oblique pictures that can be used together.
- In some digital cameras for aerial photogrammetry images from several imaging elements, sometimes with separate lenses, are geometrically corrected and combined to one image in the camera.