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This paper presents a catalogue of optimised pointings for differentialphotometry of 23,779 quasars extracted from the Sloan Digital Sky Survey (SDSS)Catalogue and a score for each indicating the quality of the Field of View(FoV) associated with that pointing. Observation of millimagnitude variabilityon a timescale of minutes typically requires differential observations withreference to an ensemble of reference stars. For optimal performance, thesereference stars should have similar colour and magnitude to the target quasar.In addition, the greatest quantity and quality of suitable reference stars maybe found by using a telescope pointing which offsets the target object from thecentre of the field of view. By comparing each quasar with the stars whichappear close to it on the sky in the SDSS Catalogue, an optimum pointing can becalculated, and a figure of merit, referred to as the "score" calculated forthat pointing. Highly flexible software has been developed to enable thisprocess to be automated and implemented in a distributed computing paradigm,which enables the creation of catalogues of pointings given a set of inputtargets. Applying this technique to a sample of 40,000 targets from the 4thSDSS quasar catalogue resulted in the production of pointings and scores for23,779 quasars. This catalogue is a useful resource for observers planningdifferential photometry studies and surveys of quasars to select those whichhave many suitable celestial neighbours for differential photometry

A Catalogue of Locus Algorithm Pointings for Optimal Differential Photometry for 23,779 Quasars