The 'photogrammetric stereomodel' from two overlapping aerial photos allows determination of:
Choose the correct answer
Only 2D planimetric positions without height
3D ground coordinates (X, Y, Z) from parallax between two overlapping photos — enables DEM and full mapping
Only colour information
Wind speed at flight altitude
Correct Answer
B. 3D ground coordinates (X, Y, Z) from parallax between two overlapping photos — enables DEM and full mapping
Why is this the answer?
Stereoscopic model: two photos with overlap (endlap 60%, sidelap 30%) form stereomodel when viewed simultaneously. From parallax differences: 3D coordinates of ground points measurable. Output: DEM (Digital Elevation Model), orthophoto, planimetric map. Base-height ratio (B/H) determines height accuracy: Δh = H × Δp / (B) where Δp = parallax measurement error. Analytical photogrammetry → digital photogrammetry (SfM).
Related Surveying MCQs
More solved Surveying questions for AE/JE Civil Engineering exams.
- 'Contour interval' selection for a topographic survey depends on:
- A 'Digital Elevation Model' (DEM) is used in GIS for:
- The 'photogrammetric control' (ground control points) in aerial survey are required for:
- The 'EDM' (Electronic Distance Measurement) instrument measures distances using:
- The 'corrections' applied to measured chain/tape lengths include all EXCEPT:
- The 'levelling staff' reading is corrected for 'curvature and refraction' by the formula:
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