---
title: "Short note: Importance and uses of photogrammetry"
subject: "Surveying II"
chapter: 7
key: "semester_4/surveying_ii:photogrammetry-importance-uses"
source: https://www.bctengineer.com/q/semester_4/surveying_ii/photogrammetry-importance-uses
site: BCT Engineering
---

# Short note: Importance and uses of photogrammetry

Surveying II · Chapter 7: Photogrammetry and Remote Sensing

- Asked in: 2071 Magh, 4 marks
- Video: [Advantages and Disadvantages of Photogrammetry](https://www.youtube.com/watch?v=S9IKLF0KtLw) — Photogrammetry Academic
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_4/surveying_ii/photogrammetry-importance-uses
- Whole chapter: https://www.bctengineer.com/md/semester_4/surveying_ii/chapter-7

## Question

Write a short note on the importance and uses of photogrammetry.

## Short answer

Photogrammetry gives accurate, low-cost maps and measurements, reducing fieldwork and allowing work in hazardous areas. It is used for topographic mapping, engineering site investigation, volume computation, cadastral surveys, and deformation monitoring.

## Answer

**Photogrammetry** is the science and art of obtaining reliable measurements and maps of objects and terrain from photographs. Its main branches are aerial photogrammetry (camera in an aircraft) and terrestrial or close-range photogrammetry (camera on or near the ground).

#### Importance
- Provides fast, accurate maps of very large areas at a lower cost than ground survey.
- Gives a permanent, objective record of the ground that can be re-measured at any time.
- Makes measurement possible in inaccessible, dangerous or restricted places.
- Produces many outputs from one set of photos: planimetric maps, contour maps, DEMs and orthophotos.
- Reduces field work, so projects are finished in less time.

#### Uses
- Topographic and large-scale engineering mapping.
- Route and site investigation (roads, railways, canals, dams, transmission lines).
- Volume computation of earthwork and quarries.
- Cadastral surveys and land-use planning.
- Geology, forestry, agriculture and urban planning.
- Structural deformation, monument and archaeological documentation (close range).
- Disaster damage assessment and flood mapping.

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. Photogrammetry is:
   A. Measuring with chains
   B. Obtaining reliable measurements and maps from photographs
   C. Satellite orbit design
   D. Soil testing
   Answer: B. It is the science and art of measuring from photographs. (Key point: Definition)

2. Which is an importance?
   A. Cheaper than ground survey for small plots
   B. Needs no photos
   C. Cannot be re-measured
   D. Fast, accurate maps of large areas at lower cost than ground survey
   Answer: D. Photos give a permanent record that can be re-measured and reduce field work. (Key point: Importance)

3. Outputs from one set of photos include:
   A. Only text
   B. Planimetric maps, contour maps, DEMs, orthophotos
   C. Only coordinates of benchmarks
   D. Only soil data
   Answer: B. Many products come from one photo set. (Key point: Outputs)

4. Which is a use?
   A. Concrete curing
   B. Bolt tightening
   C. Pump design
   D. Earthwork and quarry volume computation
   Answer: D. Photogrammetry measures volumes, cross-sections, cadastral and more. (Key point: Uses)

## Related in Surveying II

- [Short note: Photo scale, photogrammetry uses](https://www.bctengineer.com/question.md?key=semester_4%2Fsurveying_ii%3Aphoto-scale-photogrammetry-uses) — Surveying II, chapter 7
- [Short note: Photogrammetry limitation and uses](https://www.bctengineer.com/question.md?key=semester_4%2Fsurveying_ii%3Aphotogrammetry-limitations-uses) — Surveying II, chapter 7