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What is Photogrammetry?

Updated: May 7

The process of photogrammetry encompasses the science and technologies of obtaining exact measurements within photographs, as well as the 3D data from those photographs. The use of overlapping images and images obtained from different angles allows photogrammetry to build reconstructions—both physical and digital—of objects, landscapes, and buildings. Photogrammetry is essential to geospatial mapping, surveying, engineering, construction, and numerous new technologies such as drones and digital twins.


Photogrammetry combines photography, mathematics, and computer vision to derive geometric properties from images. The core idea is simple: when the same point is visible in multiple images, its 3D position can be calculated through triangulation.


Photogrammetry is broadly categorized into:


  • Aerial Photogrammetry – Images captured from drones, aircraft, or satellites

  • Terrestrial (Close-Range) Photogrammetry – Ground-based photography for objects, buildings, or small areas



Photogrammetric Services (DTM extraction, DSM generation, Planimetric extraction, Contour generation, Point cloud classification, Volumetric calculations, and 3D modeling)
Photogrammetric Services (DTM extraction, DSM generation, Planimetric extraction, Contour generation, Point cloud classification, Volumetric calculations, and 3D modeling)

How Photogrammetry Works


A structure is followed to create 3D geographic data from images through photogrammetry.


  1. Image Acquisition- high-quality images are taken with overlapping shots approximately 70-80 % forward and 60-70% sideways with the use of either a UAV or an airplane. or handheld camera


  1. Feature Detection and Matching- Algorithms such as SIFT or SURF are used to detect common key points (features) on multiple images.


  1. Camera Alignment (Bundle Adjustment)- The system uses all the matched features from the camera alignment process using a 3D model to adjust camera locations and angles while reducing error.


  1. Point Cloud Generation- The matched features will create a sparse, then dense point cloud representing an object's surface geometry.


  1. Mesh Creation- The point cloud will be converted into a triangulated surface mesh


  1. Applying Texture- Once the surface mesh is created, high-resolution textures from images will be applied to the surface mesh to give the structure the appearance of reality.


  1. Orthomosaic and Digital Elevation Model Creation


  • Orthomosaic: a contiguous collection of photographs that creates a single image

  • DEM (Digital Elevation Model): a representation of the surface elevation above a common datum.

https://www.youtube.com/watch?v=rpdCJRmQqkk
Photogrammetry vs LiDAR Technical Comparison

Key Components of Photogrammetry


  • Camera Calibration: Determining lens distortion and internal parameters.

  • Ground Control Points (GCPs): Locations with known coordinates used to increase accuracy.

  • Tie Points: Similar characteristics found between images.

  • Georeferencing data: Displaying data in relation to real-world coordinate systems, e.g., WGS84.


Applications of Photogrammetry


Photogrammetry can be used in different fields.


  1. Surveying and Mapping


  • Creating topographic maps

  • Completing land boundary surveys

  • Creating GIS data


  1. Construction and Engineering


  • Monitoring site and tracking progress

  • Calculating volume cut/fill analyses.

  • Documenting how a building was built



  • Analyzing the health of crops

  • Mapping fields and improving crop yields


  1. Mining and Quarrying


  • Measuring stockpiles

  • Analyzing terrain

  • Monitoring safety


  1. Architecture and Cultural Heritage


  • Creating 3D models of historical locations

  • Developing restoration plans


  1. Environmental Monitoring


  • Mapping forests

  • Tracking coastal erosion

  • Evaluating damage after a disaster


  1. Media and Gaming


  • Developing 3D assets

  • Creating virtual reality environments


Advantages of Photogrammetry


  • Economical compared to conventional surveying

  • Highly accurate when correct control points are utilized

  • No-contact measurements (ideal for the safety of hazardous areas)

  • Scalable to be used for small objects all the way up to large landscapes

  • Provides rich visual data and realistic textures.


The Future of Photogrammetry


Photogrammetry continues to improve with technology advancements in the following areas:


  • AI and Machine Learning

  • Real-time 3D furniture reconstruction

  • Integration with BIM and Digital Twins

  • Autonomous drone mapping.


As technology advances, Photogrammetry is getting quicker and more available (to more users), plus more accurate.


Photogrammetry is an incredibly powerful technology that allows users to utilize commonplace photos to create highly accurate 3D models or maps of any given subject. Its uses are very wide-ranging and applicable across many industries, including construction and environmental science. Today, it is an important part of our data-driven society.


As a GIS or Surveyor/Drone operator or other users, knowledge of photogrammetry has a significant impact on workflow and making good decisions.


For more information or any questions regarding Photogrammetry, please don't hesitate to contact us at


USA (HQ): (720) 702–4849

India: 98260-76466 - Pradeep Shrivastava

Canada: (519) 590 9999

Mexico: 55 5941 3755

UK & Spain: +44 12358 56710



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