SpaceSurvey deliverables
DTM, DSM and orthomosaic: choose the right mapping product
Three common outputs answer different questions about terrain, surfaces and site context.
Start with the question
A project can receive attractive maps and still lack the information needed for design. SpaceChamps recommends agreeing the intended use of each output before selecting acquisition settings. Drainage analysis, rooftop inspection and site visualization need different representations of the same place. A deliverable list should state purpose as well as file format.
Terrain and surface are different
A digital terrain model aims to represent the ground surface. A digital surface model includes visible upper surfaces such as buildings and vegetation. They should not be substituted without checking the application. A terrain model depends on ground observations, classification and interpolation choices; a small pixel size alone does not demonstrate either detail or accuracy.
An orthomosaic adds visual context
An orthomosaic combines corrected aerial imagery into a geographically referenced image. It can help teams recognize roads, structures, land cover and site activity. It does not show buried assets, prove legal boundaries or guarantee that features hidden by vegetation were captured. Image date, ground sampling distance, reference system and known gaps should accompany delivery.
Write an acceptance checklist
Agree horizontal and vertical reference systems, units, extent and buffer, resolution, classification and accuracy reporting. Ask for sample files that open in the client’s GIS or CAD software. Specify whether contours, breaklines or cross-sections are included rather than assuming they arrive with every elevation raster. Retain metadata connecting each output to acquisition and processing. SpaceChamps can scope these products individually or as a coordinated package for infrastructure and land projects.