Buchanan, Thomas2010-03-082016-03-312010-03-082016-03-311992321897420http://nbn-resolving.de/urn:nbn:de:bsz:93-opus-51414http://elib.uni-stuttgart.de/handle/11682/7176http://dx.doi.org/10.18419/opus-7159We prove that in general the critical set for photogrammetric reconstruction using lines in P 3 (C) is a line congruence Γ of order 3 and class 6; Γ has 10 singular points and no singular planes. The general hyperplane sections of Γ (ruled surfaces formed by intersecting Γ with linear line complexes) have genus 5. Γ can be found in Fano's classification of congruences of order 3, and further properties of Γ can be found in the literature.eninfo:eu-repo/semantics/openAccessPhotogrammetrie , Dreidimensionale Rekonstruktion510article