Assuming that the camera is mounted such that the camera looks down and the top of the image points to the front of the aircraft, the yaw, pitch, roll angles are defined as follows:

Camera focal lengthcomparison

A conversion lens is attached to a lens to enable it to take photos with a wider angle or stronger telephoto magnification.

Focal lengthof lens formula

Yaw, Pitch, Roll and Omega, Phi, Kappa angles define the orientation of the drone or the camera during the image acquisition. This article provides definitions of Yaw, Pitch, Roll and Omega, Phi, Kappa angles, as well as how to convert and use these angles in Pix4D products.

This is a lens used for close-up photography. A macro lens can shoot from a distance closer to the subject than a regular lens. The GXR interchangeable unit camera system has a camera unit with a 50 mm macro lens. Link to more information on GXR camera unit

Nikoncamera focal length

Since the definition of Yaw, Pitch, and Roll may vary for different UAV manufacturers, it is not possible to guarantee that Omega, Phi, and Kappa can be calculated accurately for all UAVs.

At the moment, the processing options that directly influence the use of the orientation angles can only be selected in PIX4Dmapper.

Attaching a 1.88x teleconversion lens to a 72 mm lens gives an angle of view equivalent to a 135 mm medium telephoto lens.

Cameralens distance chart

Successfully converting from Yaw, Pitch, and Roll to Omega, Phi, and Kappa depends on several factors, including the camera's position on Earth.

* The GXR interchangeable unit camera system has camera units with a fixed focal length lens and camera units with a zoom lens.

Yaw, Pitch, Roll angles define the relation between the navigation coordinate system and the body coordinate system. The coordinate systems and rotations are defined as:

Telephoto lensfocal length

Camera focal lengthchart

Most drone manufacturers write Yaw, Pitch, and Roll angle values directly in the EXIF tags of the images. If the EXIF tags are available, the values will be automatically converted to Omega, Phi, and Kappa when importing the images into Pix4D products. For more information: Specifications of xmp.camera tags.

With a zoom lens, when you turn on macro mode and move as close as possible while still keeping the subject in focus, the minimum distance to the subject and the size of the subject in the frame will differ depending on whether the lens is at a wide-angle or telephoto zoom position. With a wide-angle setting you may be too close and with a telephoto setting you may be too far away so adjust the focal length to find the one that makes it easiest to take the shots you want.

It is possible to test the accuracy of the initial Omega, Phi, and Kappa values according to the variance (RMS) that appears in the Quality Report or compare the initial orientation with the optimized orientation calculated by PIX4Dmapper.

The angle indicating the width of the field included in the photo is called the "angle of view." A wide-angle lens has a wide angle of view and a telephoto lens has a narrow angle of view.

The distance from the center of the lens to the image focal point (=image sensor surface) is known as the focal length. It is expressed in millimeter (mm) units. A lens with a short focal length is a wide-angle lens and one with a long focal length is a telephoto lens.

Even if the focal lengths of the lenses of two digital cameras are the same, the angle of view can vary depending on the size of the image sensor used in each. To make it easier to understand angle of view, focal length is often expressed as "__ mm equivalent," which means it has been converted to the 35 mm film camera format that has been historically the most common. Here on this site also, we state focal lengths that are converted into 35 mm film camera format.

What isfocal lengthof lens

More information about the coordinate system definition, see the How are the Internal and External Camera Parameters defined? article.

The omega, phi, kappa angles are defined as the angles used in order to rotate a (X, Y, Z) geodetic coordinate system and align it with the image coordinate system. The rotations are applied in the following order:

There are many ways to convert Yaw, Pitch, and Roll to Omega, Phi, and Kappa. Pix4D's method is described in the attached documents:

Attaching a 0.75x wide conversion lens to a 28 mm lens gives an angle of view equivalent to a 21 mm ultra wide-angle lens.

Phonecamera focal length

Yaw, Pitch, Roll definitionOmega, Phi, Kappa definitionHow to convert Yaw, Pitch, Roll to Omega, Phi, KappaUsing Omega, Phi, Kappa and Yaw, Pitch, Roll angles in Pix4D

Accurate angle values can be incorporated to accelerate processing time and produce more accurate results using the Accurate Geolocation and Orientation Calibration Method: Menu Process > Processing Options... > 1. Initial Processing > Calibration - PIX4Dmapper.

To test the accuracy of the initial Omega, Phi, and Kappa values apply Standard or Alternative Calibration Method: Menu Process > Processing Options... > 1. Initial Processing > Calibration - PIX4Dmapper.