Introduction To Photogrammetry: Development Cycles of The Photogrammetry
Introduction To Photogrammetry: Development Cycles of The Photogrammetry
Introduction To Photogrammetry: Development Cycles of The Photogrammetry
Introduction to Photogrammetry
t is a science and technology to derive the spatial measurement and other
mathematical products from the photograph. The word photogrammetry is made
from three Greek words.
The development of the photogrammetry from year 1850 went through different
cycles, each cycles is of around 50 years.
Plane Table Photogrammetry: This cycle started form year 1850 to year 1900
Application of Photogrammetry:
1. Topographic Maps
2. Creation of Orthoimages, Digital Elevation Models, Virtual Landscapes
3. Nadir image which is important for the mapping
4. Overlap and sidelap is required to provide 3D information
5. Land Survey and Highway Engineering
6. Creating different type of maps, tax maps, soil maps, forest maps, geologic
maps
7. Photogrammetry is also used for traffic management system
8. It is heavily used by the Military System: mission planning, rehearsal and
targeting
Types of Photogrammetry: Photogrammetry can be classified in different ways but
the standard way is to split into two fields based on the mounted camera position.
On this basis we have Aerial Photogrammetry and Close Range Photogrammetry
The name “photogrammetry" is derived from the three Greek words phos or phot
which means light, gramma which means letter or something drawn, and metrein,
the noun of measure
Types of Photogrammetry
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When to Use Photogrammetry
Each project has a unique set of conditions that will determine which mapping
techniques should be utilized. Surveys in consultation with the Project Manager
will determine if photogrammetry will be used on a project
The following are factors to consider when deciding to use Photogrammetry:
• Photogrammetry is a cost efficient surveying method for mapping large areas.
• Photogrammetry may be safer than other surveying methods. It is safer to take
photographs of a dangerous area than to place surveyors in harms way.
• Photogrammetry provides the ability to map areas inaccessible to field crews.
• Photogrammetry creates a photographic record of the project site (snapshot in
time).
• Photogrammetry produces useful digital products such as orthophotos.
• Photogrammetry produces electronic terrain models.
• The accuracy required for a mapping project is greater than the accuracy
achievable with photogrammetric methods.
• The scope of the work is not large enough to justify the costs of surveying the
photo control and performing the subsequent photogrammetric processes.
However, when unsafe field conditions are encountered, safety shall hold a higher
weight than cost in the decision process.
Geometric Characteristics of Aerial Photographs: