Figure 1.

Workflow of the photogrammetric method to measure physical aperture: (a) Kuru grey granite sample with a throughgoing rough fracture, (b) top and half parts of the sample are scanned together and separately, (c) cameras used to capture the images of the sample, (d) photogrammetric processing and the calculated camera positions of the whole sample, (e) photogrammetric processing and the calculated camera positions of the two halves, (f) defined distances between markers on the whole sample, (g) defined coordinate system for the whole sample and extracting each marker position in the same coordinate system, (h) 3D point cloud of the sample with top and bottom halves matched in the same coordinate system with applying obtained markers’ positions for each half, (i) physical aperture distribution measured from the digital model, (j) profile extraction, and (k) Joint Roughness Coefficient (JRC) estimation.