Photogrammetry Surveying - Its Types, and Applications

What is Photogrammetry Surveying?

Photogrammetry surveying means the measurement from photographs. It includes two words “photo,” and “meter.” More precisely, it’s a surveying technique in which arts, science, and technology are used for collecting, recording, and measuring physical objects and the environment from photographs.

There are two types of photogrammetry surveying:

1. Terrestrial Photogrammetry Surveying
2. Aerial Photogrammetry Surveying

In this civil engineering article, you will learn about the two types of photogrammetry surveying methods, their applications, benefits, and drawbacks.

Terrestrial Photogrammetry Surveying

The terrestrial photogrammetry technique involves the measurement of photographs taken from a fixed point on the ground level. In this method, photographs are taken by handheld camera or placing the camera on a tripod. This photogrammetry technique is useful for creating 3D models of the object but not used for topographical mapping.

Benefits and Drawbacks of Terrestrial Photogrammetry Surveying

Benefits

• Terrestrial photogrammetry provides high-resolution, high-precision, fast, and easy measurement as compared to other methods.
• The cost of measurement by this method is also low as compared to other measuring techniques.
• The setup is easily transportable. It’s best for small and close-range projects.

Drawbacks:

• Processing of data in this method is complex and requires special expertise. Due to lengthy and complex processing, it’s also time-consuming.
• The geometry (position and distance of camera) of the survey influence the precision, quality, and resolution of the photographs.
• It may be difficult to take photographs in some areas, high-traffic areas, etc.

Aerial Photogrammetry Surveying

It is a photogrammetry technique in which photographs or video recordings are taken from a higher elevation from the earth’s surface, like from a helicopter or aircraft. This method is useful for large transportation projects and military intelligence. It provides topographical and cultural features of the object.

Benefits and Drawbacks of Aerial Photogrammetry Surveying

Benefits:

• One of the major benefits of aerial photogrammetry surveying is it provides a real and permanent recording of a situation. So, there is no need to do fieldwork anymore; these recordings can be used for further measurements.
• Since it provides a wider view of the project, it’s easier to study and measure other lines as well. The broad view of the project field is better than any other traditional measuring technique.
• It’s convenient for areas that are not safe or difficult to measure. Again, there is no issue of disturbing the traffic for measurement as it takes photographs from the air.

Drawbacks:

• Bad weather and climate can affect aerial photogrammetry surveying. Wind, haze, the cloud can disturb while taking photographs which may result in poor quality images.
• Any objects such as trees, roofs, a canopy can block while taking the photographs. So, it cannot take clear pictures of the road, which will be a big problem during measurement.

For successful photogrammetry surveying, it’s essential to understand different components, proper planning, and execution of various processes. Hopefully, the above information has helped you understand photogrammetry, its types, benefits, and drawbacks.