Photogrammetry vs LiDAR - which one, when
Photogrammetry stitches overlapping aerial photos into an orthomosaic and a point cloud. Cheaper, faster, beautiful imagery, good vertical accuracy in open terrain. LiDAR fires laser pulses to build a point cloud directly. More expensive, slower, but penetrates vegetation canopy to surface real terrain underneath and produces higher-fidelity edge detail. Pick photogrammetry for open construction / mining / civil; LiDAR for forestry, dense vegetation, fine-detail engineering, or anywhere you need bare-earth DTM under tree cover.