A dental 3D camera for optically scanning a three-dimensional object, and a method for operating a dental 3D camera. The camera operates in accordance with a triangulation procedure to acquire a plurality of images of the object. The method comprises forming at least one comparative signal based on at least two images of the object acquired by the camera while at least one pattern is projected on the object, and determining at least one camera shake index based on the at least one comparative signal.
