There are various methods to capturing an object to create a 3D model but the most common are Laser Scanning (costly equipment but more accurate) or Digital photogrammetry (less accurate but only needs digital camera). Laser scanning projects a light as the object rotates on a turntable, while Digital photogrammetry uses a digital camera that moves around the stationary object. This is the method we used to capture our sculpted Head.
Even though the Digital method is not as precise as the Laser scan, you can get very good results if the 3D scanning scene is setup properly. Photogrammetry takes measurements from multiple photographs, then uses the XYZ coordinates of the points to generate 3D digital models. More points of reference provides accurate digital information, resulting in less time to clean up the 3D model to prepare for fabrication.
Photogrammetry does not play well with large blank surfaces like tables and walls. It needs non-moving points of reference in order to stitch together the 60 image captures (think of sewing a garment, seams have to line up).
Testing, Testing 1-2-3
For the first test we kept the studio decor was ‘as is’ to see the if the capture of the Head could be successful with minimal effort. Uploaded the images to 123D Catch to stitch together to create the 3D model. Nope, sorry kids, not enough info to create the 3D model, you need to decorate the space.
Additional tests with the new backgrounds were promising but getting the camera to cooperate was another challenge. We tried high-end, middle and pocket cameras, each had their own special quirks, again resulting in partial captures of the Head object.
As a final, exasperating test we used an iPod Touch with Camera 360 app (also for Android) to shoot the 60 images, uploaded to 123D Catch again, held our breathe and waited….. then the clouds parted while a chorus of angels sang…. “See the pretty Head in the middle there…“