Photogrammetry – Types of Photographs

In photogrammetry, aerial photographs are categorized based on camera orientation, coverage, and spectral sensitivity. Below is a breakdown of the major types:

1️⃣ Based on Camera Axis Orientation

Type	Description	Key Feature
Vertical Photo	Taken with the camera axis pointing directly downward (within 3° of vertical).	Used for maps and measurements
Oblique Photo	Taken with the camera axis tilted away from vertical.	Covers more area but with distortions

Low Oblique: Horizon not visible
High Oblique: Horizon visible

2️⃣ Based on Number of Photos Taken

Type	Description
Single Photo	One image taken of an area
Stereoscopic Pair	Two overlapping photos for 3D viewing and depth analysis
Strip or Mosaic	Series of overlapping photos covering a long area, useful in mapping large regions

3️⃣ Based on Spectral Sensitivity

Type	Description	Application
Panchromatic	Captures images in black and white	General mapping
Infrared (IR)	Sensitive to infrared radiation	Vegetation, water, heat
Color	Natural color images	Urban studies, land use
Color Infrared (CIR)	Uses IR, red, and green bands	Health of vegetation, hydrology

4️⃣ Based on Lens Angle

Type	Field of View
Narrow-angle	Small area, high detail
Normal-angle	Medium coverage
Wide-angle	Large area, less detail
Super wide-angle / Fisheye	Very large area, with extreme distortion

5️⃣ Based on Time and Platform

Type	Platform
Aerial Photo	Taken from aircraft or drones
Satellite Image	Taken from orbiting satellites
Terrestrial Photo	Taken from ground level (horizontal photos)

✅ Summary Table

Orientation	Number	Spectrum	Field of View	Platform
Vertical / Oblique	Single / Stereo	Panchromatic / IR / CIR	Narrow / Wide	Aerial / Satellite / Terrestrial

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