© Crown copyright and database rights 2025 Ordnance Survey 0100031673

OS MasterMap Imagery Layer provides a reliable and consistent source of orthorectified, aerial photography at 25cm resolution for general business use.  The product is colour-balanced, and edge matched to minimise misalignment or inconsistency at image boundaries.

OS MasterMap Imagery Layer is used in a variety of use cases. Features align consistently with OS MasterMap Topography Layer data to add visual and contextual capability, considerably enhancing mapping projects for surveyors, engineers, planners and many more:

- site evaluation
- land-use cover/land use analysis
- property management and planning applications
- asset management
- property insurance
- risk analysis
- route planning and site accessibility
- environmental monitoring

Ordnance Survey has invested considerable resources to provide orthorectified imagery that achieves the consistently high standard for shape, position and colour.  Priority is given to positional accuracy and ensuring details can be seen within shadows, with consistent mosaicing and edgematching between areas of imagery collected at different times.  The data has a stated accuracy of 1.1m root-mean-square error (RMSE) and is typically between 3 and 5 years old.