Digitally Capturing the McDougall Church
Two approaches were used to digitally capture the McDougall United Memorial Church. A Z+F 5010X laser scanner was used to capture the exterior of the building, while a Phantom 4 drone with Pix4D was used to image what remained of the interior.
Scanning the church after the fire presented many challenges. First, the darkening of the exterior caused by the fire damage made acquiring color data for the point cloud difficult. Second, a large amount of debris was distributed in areas around what remained of the church, which restricted where we could place the scanner.
Extensive damage to the interior and floor made scanning inside the church impossible. This problem was solved by using the drone to fly over the church in a grid pattern to capture the interior and any details, such as the altar and piano, that remained.
Six paddle targets were strategically placed around the exterior of the church, such that no less than three were visible from each scanning location. The building was then captured in its entirety from 8 scanning locations around the outside. The scans were registered using Z+F Laser Control software, and then exported into AutoDesk ReCap for further processing. The resulting point cloud was imported into AutoDesk ReMake to create a 3D model of the building.
The DJI drone was flown in an overlapping grid over the church at an altitude of 20 meters, such that the images captured by the onboard camera overlapped by 90%. The resulting images were processed using Pix4D mapper software, creating a point cloud, 3D model, DSM, and orthomosaic of the site.
Accurate data has been taken directly off the point cloud of the church, including heights and lengths of what remains of the standing walls, and distances from the building to a nearby stone memorial.
Specific architectural details which are visible in the point clouds will provide important information should the church ever be reconstructed.