Photogrammetry
Types of Photographs
By
Prasenjit Bhowmick
Asst. Professor
DREAM INSTITUTE OF TECHNOLOGY
Civil Engineering Dept.
Types of photographs
vertical,
horizontal,
oblique.
Topics
Types of Photographs
Photogrammetry
Photographs
Errestrial
Taken from
ground based
cameras
Aerial
Taken from
air based
cameras
Types of Aerial Photographs
Photogrammetry
Aerial
Photographs
According to
orientation of
camera axis
According to
Lens system
According
Film
properties
1. According to orientation of camera axis
Photogrammetry
1
Vertical Oblique
•dependsupontheangleofthecamera
•withrespecttotheearth'ssurface
Vertical Photographs
Camera points should straight down
Allowable tolerance is ±3°with plumb line.
Photogrammetry
Characteristics
Axis perpendicular to the earth
Covers small area
Photogrammetry
Characteristics
Distance and directions from flat terrain
Relief not readily apparent
Photogrammetry
Relationship of the vertical aerial photograph with the ground
Photogrammetry
Low Oblique Photographs
Photogrammetry
Camera
inclined about
30°from the
vertical
Characteristics -
Covers a large area
Ground area covered as trapezoid,
square or rectangular
Photogrammetry
Characteristics –
Familiar than viewing from the top of
tall object.
Photogrammetry
Characteristics –
No distance & Azimuth can measure
with Scale.
Does not show the horizon
Photogrammetry
Relationship of low oblique photograph to the ground
Photogrammetry
High Oblique Photographs
Camera inclined about 60°from the
vertical
Limited military application
Photogrammetry
Characteristics -
Covers a very large area
Distances and directions are not
measured
Photogrammetry
Characteristics -
Relief may be quite discernible but
distorted as in any oblique view.
Photogrammetry
Characteristics -
The horizon is always visible.
Photogrammetry