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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

TypeDescriptionKey Feature
Vertical PhotoTaken with the camera axis pointing directly downward (within 3° of vertical).Used for maps and measurements
Oblique PhotoTaken 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

TypeDescription
Single PhotoOne image taken of an area
Stereoscopic PairTwo overlapping photos for 3D viewing and depth analysis
Strip or MosaicSeries of overlapping photos covering a long area, useful in mapping large regions

3️⃣ Based on Spectral Sensitivity

TypeDescriptionApplication
PanchromaticCaptures images in black and whiteGeneral mapping
Infrared (IR)Sensitive to infrared radiationVegetation, water, heat
ColorNatural color imagesUrban studies, land use
Color Infrared (CIR)Uses IR, red, and green bandsHealth of vegetation, hydrology

4️⃣ Based on Lens Angle

TypeField of View
Narrow-angleSmall area, high detail
Normal-angleMedium coverage
Wide-angleLarge area, less detail
Super wide-angle / FisheyeVery large area, with extreme distortion

5️⃣ Based on Time and Platform

TypePlatform
Aerial PhotoTaken from aircraft or drones
Satellite ImageTaken from orbiting satellites
Terrestrial PhotoTaken from ground level (horizontal photos)

✅ Summary Table

OrientationNumberSpectrumField of ViewPlatform
Vertical / ObliqueSingle / StereoPanchromatic / IR / CIRNarrow / WideAerial / Satellite / Terrestrial

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