Photogrammetry Services

Photogrammetry

Photogrammetry_1

ARSG offers a full range of high quality photogrammetry services, from small, technically challenging projects to large, high volume work. ARSG has the capacity and expertise to deliver superior quality results quickly and cost effectively. With our dynamic approach, we can provide either a complete production solution or phased deliverables as required.

Our services include:

  • project management
  • flight planning and GCP surveys
  • aerial photo acquisition
  • scanning
  • aero triangulation
  • planimetric mapping
  • digital elevation and terrain modelling (DEM/DTM)
  • map editing
  • digital orthophotography

 

Project Planning and Management

  • Dedication to the technical specifications, delivery schedule and client expectations are key to project success.
  • Experienced project managers liaise with clients and oversee all project stages.
  • Rigorous quality control procedures and interim progress reports are standard.

 

Flight and GCP Planning and Aerial Photo Acquisition

  • Detailed flight planning with the optimal amount of ground surveying keeps costs manageable without reducing accuracy.
  • Airborne GPS is used to bolster accuracy and reduce costly field surveys wherever possible.
  • Local survey partners may gather the GCP coordinates while local aircraft use USGS-calibrated cameras.
  • Black & white, color and infra-red photography requirements are all accommodated.
  • Detailed, advanced film inspection is also available.

 

Aero triangulation

Aero triangulation_1

  • State-of-the-art Softcopy photogrammetric workstations are used.
  • Automated AT is available but manual AT processing is preferred for its higher accuracy.
  • A root mean square (RMS) error of less than [1/10,000 times flying height] is typical.

 

Topographic and Planimetric Feature Extraction

  • Extraction occurs in a Micro station environment and can be exported to any CAD/GIS format.
  • Planimetric feature extraction follows applicable feature tables or database dictionaries.
  • High quality DTM, DEM and/or contour files are derived by our team of experienced photogrammetrists.
  • ARSG has extensive expertise with large and small scale mapping (1″=40’ and smaller).

 

Digital Elevation and Terrain Modeling (DEM, DTM)

Digital Elevation and Terrain Modeling (DEM, DTM)_1

  • ARSG excels at high
  •  resolution TIN and surface model preparation.
  • Optimal data collection methods and meticulous modelling capabilities are implemented.
  • Automatic contour generation and advanced manual contour smoothing can be performed.
  • ARSG has expertise in working with hard and soft breaklines and high density mass points.

 

Map Editing

  • ARSG delivers innovative mapsheet layout and design with advanced contour interpolation.
  • Cleaning and topological structuring of planimetric data is also provided.
  • A variety of cartographic editing, layout and separation processes are available.

 

 Digital Orthophotography

Digital Orthophotography_1

  • ARSG uses the latest, superior quality orthorectification techniques.
  • Advanced methods used to correct camera, lens and relief distortions.
  • Further processing includes precise dodging, mosaicking and global tone balancing.
  • Seamlines are generated automatically and edited manually to ensure seamlessness between the tiles.
  • Special attention is given to bridges to avoid smearing at the stereo compilation level.
  • An intense quality assurance process ensures 100% adherence to customer specifications.

 

Second Generation Orthophotography Capabilities

  • Greatly reduced production costs for clients requiring new orthophotos in areas with existing data.
  • ARSG uses previous DEMs and orthos to derive GCP elevations that allow new aero triangulation adjustment for recent aerial photos.
  • The need to deploy ground survey crews and create new digital terrain and elevation models is greatly reduced.

 

Innovative Map Design and Specialized 3-D Modeling

Innovative Map Design and Specialized 3-D Modeling_1

  • High resolution, 3-D images are created from elevation data and complex triangulated irregular networks (TIN) using the latest, state-of-the-art software and rendering technology.
  • Resultant images are sun-illuminated and terrain and elevation shaded
  • These intuitive images provide rapid appreciation of terrain, grade and natural and man-made features.
  • Applications include resource extraction, infrastructure planning, utility management and recreation usage.