Pix4D SM Circular-flights-for-3D-models New Parallax 22017 07-1-e1500554262316

3D models & angles between images in circular missions

Choosing the flight plan for 3D models can be challenging. Pix4Dcapture has automatic flight missions optimized for different scenarios.

Image-angle overlap in circular missions

To help you compare, we tested variations in image-angle overlap in circular missions.

Circular missions are recommended to 3D map a single object of interest, like a building or a monument.

When it comes to circular mission settings, with Pix4Dcapture, you can choose the angle between images.

By dividing the 360° flight covered by the drone into sections, or variable angles (4°, 8°, 12°), the drone is told by the app to shoot a picture when it reaches the predefined angle.

At a practical level, this means that at a low angle value (e.g. 4°), the drone will take more images and have a bigger image overlap than a higher angle value (e.g. 12°).

A diagram showing a circular flight path.

For this test, we flew the three missions around a building with a base of 30 x 30 meters and height of 18 meters, using a DJI Phantom 4.

Each mission had a different value for the “angle between images” setting; we tested capturing images with 12°, 8° and 4°.

As constant factors, the flight altitude was 40m and the data was processed on Pix4D Cloud.

Circular mission with 12° angle between images

Flight time4 min 29 s
Number of images31
Cloud processing time10 min 8 s
Average GSD3.11 cm / 1.22 in
12 angle Pix4Dcapture-e1500380686397

Circular mission with 8° angle between images

Flight time5 min 44s
Number of images62
Cloud processing time17 min 23 s
Average GSD2.87 cm / 1.13 in
8 angle Pix4Dcapture-e1500381534704

Circular mission with 4° angle between images

Flight time9 min
Number of images124
Cloud processing time35 min 23 s
Average GSD2.84 cm / 1.12 in
4 angle Pix4Dcapture-e1500381816837

How do I choose the angle between images in circular missions?

To answer this question, it is important to define a goal of the 3D mapping project and keep in mind time and quality constraints.

By using a higher overlay level, there is more image information for the software to reconstruct an object, resulting in a more detailed 3D model. However, more data implies more time spent flying and acquiring images, and also a longer processing time.

Depending on the purpose of the 3D model, the option to manage the angle between images helps to balance time and quality: allowing you to choose from faster and more schematic reconstructions to more detailed ones.

Start flying with Pix4Dcapture today!
Free for Android and iOS.

Related articles