| QsoCatalogAll basically describes a triple (Target, Spec, Best) of objects that were flagged as QSO and that form a bunch. The triple names 3 objects and thier 'quality flags'. In the simplest case, all three objects were flagged as QSO. And all 3 have the same ra,dec and have very similar magnitudes. In that case the 'QsoCandidate' boolean flags are set for each If the distances magnitude differences are near zero, that means it is a very good match. If one or two of the types (target, spec, photo) were not flagged QSO, we look for a 'surrogate' of that type (target, spec, photo) nearby (within 1.5 arcseconds). If one is found its objectID is put in the triple and the QsoCandidate flag for that object is set to zero. The distance measures indicate the goodness of the spatial match. The psfMag difference measures indicate the goodness of the optical fit. See also QsoConcordance, QsoSpec, QsoBest and QsoTarget. |