Systems and methods are provided for orienting a hair harvesting tool relative to a follicular unit to be harvested. Further, systems and methods of implanting follicular units are provided, which are based on the orientation of the existing follicular units or based on pre-determined insertion angle. The provided systems and methods use image processing and image-generated topological skill models. In some embodiments surface fit is performed using, for example, a planar fit, quadric fit, cubic fit, mesh fit and parametric fit.
