The GSC II is an all-sky catalog based on 1" resolution scans of the photographic Sky Survey plates, at two epochs and three bandpasses, from the Palomar and UK Schmidt telescopes (DSS). Positions, magnitudes, and classifications are produced for all objects on each plate. The objects are then loaded into the COMPASS database, where multiple observations of the same object are matched and assigned a unique name. GSC 2.4.1 is the first release of the augmented GSC by adding object parameters (and new objects) from deeper surveys. - GSC 2.4.0 - UCAC5 (proper motions for GAIA sources - no new objects) - APASS dr9 (optical photometry - no new objects added) - 2MASS+6x (IR photometry, classifications + positions of new objects) - SDSS dr13 (optical photometry, classifications + positions of new objects) - VISTA - VHS dr4 (IR photometry, classifications + positions of new objects) - VISTA - VIKING dr2 (IR photometry, classifications + positions of new objects) - VST - ATLAS dr3 (optical photometry, classifications + positions of new objects) - VST - KIDS dr3 (optical photometry, classifications + positions of new objects) GSC 2.4.1.2 Added the following catalogs - PanSTARRS dr1/2 - SMSS dr1 - WISE - GALEX - ultraVISTA GSC 2.4.2 has the astrometric information updated to GAIAdr2 and became the default operational catalog mid-December 2020.