As with 3D laser scanning, photogrammetry scanning results in a point cloud from which a 3D model (MESH) can be created also with colored texture. But this time there are no lasers. This time we acquire all the data from the photos. Yes, it is true, we can get a 3D model of any object, ranging from beetles to cities (Like 3D cities in Google Maps).
Of course, to obtain good results, you need to follow certain rules and parameters for taking pictures of the subject and also for processing. The camera can be handheld or attached to an unmanned aerial vehicle (drone). We also offer drone mapping services, you can learn more about that here. In photogrammetric scanning we use calibrated cameras, we know the parameters of the internal orientation of the camera and its distortions. This is very important if we want to get geometric precision of the virtual 3D models of scanned objects. This is especially true if the models are to be used for measurements. Full geometric accuracy is not needed when using models for advertising purposes or in the gaming and film industry.
We can photogrammetry with classical geodetic measurements, aerial photogrammetry and 3D laser scanning. A typical example is when the interior and exterior of a building are scanned with a 3D laser scanner, the texture is obtained from the ground photogrammetry and the missing roof and the hard-to-reach areas are scanned from the drone. The whole project is then connected to the state coordinate system by geodetic measurements using a global navigation satellite systems receiver or a total station.
Check out a few of our 3D photogrammetry models on Sketchfab. You can move the models with your mouse or your fingers on a smartphone. Some models are also available for free download under CC Attribution license.