A method for calibrating a projection system having a plurality of projectors, and a camera. The method comprises the camera capturing an image of a calibration pattern projected on to a projection surface by a first projector of the plurality of projectors; determining a projective reconstruction using corresponding points between pixels in the captured image and pixels in the projected calibration pattern; and determining a set of solutions for intrinsic parameters of the first projector, the set of solutions converting the projective reconstruction to a Euclidean reconstruction based on minimization of reprojection error between the camera and the first projector. The method also comprises determining intrinsic parameters of the first projector by selecting the intrinsic parameters from the set of solutions according to a reprojection error with respect to another projector; and applying the selected intrinsic parameters to determine a Euclidean reconstruction of the projection surface.