Aerial photogrammetry services.
Photogrammetric survey. 3D geometry from overlapping imagery.
Photogrammetry services by UAV across infrastructure corridors, solar farms, earthworks, brownfield and large open sites. Aerial photogrammetric survey to RICS Band D / E accuracy (±10–25 mm at 1σ on hard detail) with documented GCP control and check-point verification.
In-depth guide: Drone Photogrammetry Survey Guide →
What is photogrammetry?
Photogrammetry generates accurate 3D geometry from overlapping 2D photographs. Identical features visible in multiple images at known camera positions allow the software to triangulate every pixel into a 3D point — producing a dense, georeferenced point cloud and, from that, a mesh, orthophoto, digital surface model and digital terrain model. With a documented Ground Control Point network and independent check points, UAV photogrammetry routinely achieves ±10–25 mm absolute accuracy on hard detail at 1σ — RICS Band D or E from the Measured Surveys of Land, Buildings and Utilities (3rd edition) framework.
It is the most cost-effective capture method for large open sites with low vegetation and well-textured surfaces — solar farms, brownfield development, earthworks, quarries, corridor mapping. For vegetated terrain, featureless surfaces or engineering-tolerance work, we hybridise photogrammetry with LiDAR and total-station capture. A dated, georeferenced multispectral orthomosaic from the same workflow is the habitat base map in our BNG baseline survey pack.
Angell Surveys is a RICS-regulated practice (Firm 681790). UAV operations conducted under the appropriate CAA authorisations.
How we capture.
Survey-grade photogrammetry depends on documented control and verified accuracy, not just flight planning. Every output ships with a check-point residual report.
GCP Network
Pre-marked Ground Control Points established by GNSS RTK rover or total station, distributed to cover the site at appropriate density. Targets visible at flight altitude. Coordinates traceable to OSGB36 / ODN.
Flight Plan & Overlap
Mission planning at calibrated overlap (typical 80/70%), altitude matched to required GSD, and crossed flight lines for complex terrain. Wind, light and airspace conditions all assessed before mobilisation.
Dense Reconstruction
Industry-standard photogrammetric processing (Agisoft Metashape, Pix4D, RealityCapture) on dedicated workstations. Dense point cloud, mesh, orthomosaic and DTM/DSM products derived in-house.
Independent Check Points
Independent ground points not used in bundle adjustment are observed and reported as accuracy residuals on every deliverable. The accuracy statement is measured, not advertised.
Orthorectified Imagery
Pixel-true orthophoto generated from the bundle-adjusted model. Suitable for planning, condition recording, change detection and visual context layered over CAD design files.
Volumetric Analysis
Stockpile and earthworks volumes computed against a reference surface (previous capture or design surface). Statistical confidence band reported with every volume.
How we work.
Survey Design
Site boundary, target accuracy, deliverables and access window agreed. Flight plan, GCP layout and RAMS prepared. CAA authorisations confirmed.
GCP & Capture
GCP network established and check points observed before flight. UAV photogrammetric capture executed with field QA confirming coverage before demob.
Processing
Bundle adjustment, point cloud, mesh, orthomosaic and DTM/DSM derived in-house. Accuracy verified against independent check points.
Delivery
Outputs issued to specification with accuracy report. Hosted 3D model published where required for stakeholder review.
Where this method has limits.
Photogrammetry is accurate and economical where the scene co-operates; where it does not, we say so and specify LiDAR or ground survey.
Texture and light
Image matching needs visible texture and consistent light. Uniform surfaces, deep shadow, snow and low winter sun degrade the model.
Water, glass and movement
Reflective, transparent and moving subjects produce noise or holes and are excluded from accuracy statements.
Vegetation
The model represents the canopy surface. Bare-earth levels under vegetation require LiDAR or ground observation.
Thin structures
Wires, railings and lattice work are poorly reconstructed; specify a dedicated method if they matter.
Accuracy drivers
Ground sample distance, overlap and the control network set the achievable band; flying higher or reducing overlap to save time trades accuracy directly.
Angell Surveys delivers this service across the UK from a London base, under RICS regulation, with the same documented control, check-point verification and QA on every project. Accuracy is specified and reported against the band table in RICS Measured Surveys of Land, Buildings and Utilities, 3rd edition (RICS, 2014), using independent check points rather than a marketing figure. Every aerial survey we deliver is specified to RICS Band F or better; most delivered work verifies at Band D–E, and the achieved figures are reported with the data. The aircraft and sensors we fly are described in our UAV survey fleet guide.
Photogrammetry questions.
Deciding between LiDAR and photogrammetry? Our capture methods comparison sets the two side by side with terrestrial laser scanning.
What is photogrammetry?
When should I use photogrammetry instead of LiDAR?
How accurate is UAV photogrammetry?
What software and platforms do you use?
What deliverables will I receive?
Are you RICS regulated and CAA authorised?
Photogrammetric survey, scoped and quoted within 24 hours.
Most scoping responses sent within one business day.
RICS-regulated work, led by Philip M. Angell MRICS.