What is Photogrammetry?
Photogrammetry is a method of 3D scanning where software analyzes many sequential photographs of an object taken from different angles and then uses that data to construct a 3D model. A sequence of photos can be obtained by taking individual frames from a video.
Checklist
When taking a portrait video for photogrammetry, start from the back of the head, then go around in a circle, making a full 360° rotation. For best results, consult the following checklist:
Make sure the important parts of the subject are fully in frame the whole time.
The subject must be still throughout. The video should be between 30 seconds to 1 minute long, so don’t pick a pose that will be difficult to hold for that duration!
Hold the camera (an iPhone works just fine) steady, to minimize blurring. This is easier to do when there is plenty of room around the subject and the subject is sitting while the photographer is standing.
Avoid harsh shadows, but make sure there is plenty of light for the sharpest image. Outdoors is recommended, ideally during overcast weather or when the sun is low on the horizon.
Avoid complex accessories such as jewelry, glasses, hats, etc. unless absolutely essential, bearing in mind that they may not scan correctly and might get simplified during the process in order to make a viable 3D print.
Some hairstyles that include thin strands may also get simplified in order to make a viable 3D print.