A discrete linear space sampling method and system for generating digital 3D models comprising. A plurality of digital images are acquired of a subject from a respective plurality of image sensor positions near the image sensor location. Candidate 3d-spels are identified, each 3d-spel being an image pixel corresponding to a common point on said subject. Candidate 3d-spels are rejected based on a differential analysis of the candidate 3d-spels, the remaining 3d-spels forming a set of accepted 3d-spels. 3D coordinates are calculated for each accepted 3d-spel, thereby forming a point-cloud of the subject.