Intro to Photogrammetry
Welcome to our comprehensive guide to aerial photogrammetry. If you are new to this fascinating field, fear not, as we will walk you through the basics and best practices to get you started on your aerial imaging journey. Check out the video linked above or read on to learn more.
Understanding Aerial Imagery Data:
Aerial imagery data comprises of the photos captured of the area you wish to examine. These images are acquired through aerial systems, either flown manually or via a pre-planned route, while simultaneously capturing images of the target area.
Aerial imagery can be captured from two main positions: NADIR and OBLIQUE.
NADIR: This position entails the aerial camera being positioned directly above the target area, at a 0-degree angle, offering a top-down view.
OBLIQUE: In contrast, oblique positioning involves capturing images at higher angles. The angle range varies depending on the application:
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0 to 10 degrees: Ideal for capturing images of building sites, topographic features, open areas, and stockpiles.
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15 to 25 degrees: Suited for urban and residential areas, some vegetation, and quarries.
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35 to 50 degrees: Utilized for detailed 3D modeling of buildings, facades, and specialized applications.
Importance of Ground Control Points (GCPs):
Ground Control Points (GCPs) are strategically placed markers on the Earth’s surface, typically laid out before flight in the target area. These points are accurately surveyed with precisely determined coordinates in a specific coordinate system, such as latitude, longitude, and elevation.
GCPs play a pivotal role in ensuring the accuracy and precision of the photogrammetric process. They are instrumental in post-processing workflows, serving as reference markers to improve accuracy and tie together imagery captured from aerial platforms with real-world geographic coordinates.
Embarking on Your Project:
Ready to kick-start your project? Our next tutorial will guide you through the process of uploading your aerial imagery data and adding ground control points to enhance accuracy and achieve outstanding results.
Stay tuned for our upcoming tutorial, and let’s take your aerial photogrammetry endeavors to new heights!