Phase One’s new aerial camera system put to the test

Specialists from Tripont and Interspect carried out a reference flight with Phase One’s new aerial camera system, the PayLoad P3. The new camera system was compared with a DJI Phantom P4. The comparison covers the quality of the images and the geometric reliability of the point cloud and model produced from them. The experts carried out the survey at the 800-year-old truncated tower in Somogyvámos.

In the comparison, the specialists sought to find out how faithfully the two surveying solutions reproduce reality, and how accurately they reproduce dimensions. During the survey the specialists operated for the same length of time, 20 minutes each, flew the drones at the same heights and distances, and took the same number of photos with the devices, about 600 images each.

With its 35 mm lens, the Phase One P3 iXM 100 MP can cover an area of up to 706 square metres from a distance of 25 metres. The images from the Danish camera system are highly detailed. A characteristic of the iXM cameras is their wide dynamic range, so the images are data-rich even in the shadow detail. With Phase One’s solution, thanks to the range and richness of the tones, the point cloud is generated more accurately and more densely. This matters because the more points the surveyed object is mapped with, the easier and more accurate it is to measure on it, since the positions of the points are more reliable. In aerial surveys, richness of detail and image dynamics are indispensable.

View the point cloud

View the contour lines

The P3 Payload works perfectly as a survey camera. The Interspect team of experts used Agisoft Metashape and CloudCompare software to analyse the data. During the test the specialists marked several points on the surface of the church and also measured them with a tape measure. Using the software, they evaluated the density and accuracy of the point clouds, for both the Phase One and the DJI P4.

The measured surface was 1.5 cm by tape measure, while a deviation of 4 mm was found with Phase One, as against 5 cm with the DJI. More points can be generated from Phase One’s high-resolution camera images, and they sit more accurately in place. The data richness of the images also helps us understand what we are seeing: the various patches of ground, plant species, phenomena and damage observed on the buildings, and material patterns.

Phase One’s aerial camera system has RTK, that is, real-time kinematic positioning, and is capable of producing highly accurate measurement results: as the reference flight proved, it can survey the designated monument, building or object with 4 mm accuracy. Thanks to its wide dynamic range, it also performs perfectly in high-contrast situations, so the images are detailed and data-rich.