2026-06-27T06:40:59Zivo://CDS.VizieR/II/2082025-05-19T09:50:00ZIIIVOABVRI CCD photometry in the field of M 31Deep BVRI CCD photometry was performed on a 1 square degree region of M31. The observations were made between September 12 and September 27, 1990, using the McGraw-Hill 1.3m telescope at the Michigan-Dartmouth-MIT (MDM) observatory at Kitt Peak. The catalogue has typical completion limits of 22.3Bmag, 22.2Vmag, 22.2Rmag and 20.9Imag. Photometric accuracy is about 2% at Vmag=19. The final astrometric calibrations take into account the systematic error discovered in the Berkhuijsen etal (1987) catalog (Magnier etal 1993). They are in the J2000 system and are eventually tied to the HST Guide Star Catalog. The final photometric calibrations are tied via the NGC 206 region to photometry taken at the Michigan-Dartmouth-MIT (MDM) 1.3m in September and October 1993. These are tied to the Landolt (1992) system of standard stars, and are in the Johnson-Kron-Cousins system (BVRcIc). Caveats: There are several known problems with the catalog. First, there are likely to be some repeated detections of certain sources (i.e., multiple entries for the same object). Second, the wings of bright sources in some cases may be included as distinct sources. Third, the completeness limits are a strong function of position, and a much lower near the core and the core of M32. Fourth, variable stars, blended star, and stars with cosmic ray hits, cosmetic problems or other failures may have highly abnormal colors and magnitudes. In general, we expect these problems to be small, but the user is cautioned to watch for these possible problems.ccd-photometryobservational-astronomyhttps://dc.g-vo.org/rr/q/lp/custom/CDS.VizieR/II/208https://cdsarc.cds.unistra.fr/viz-bin/cat/II/2081992A&AS...96..379Mhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=II/208Cone search capability for table II/208/bv (Stars with both B and V photometry)Magnier E.A.Lewin W.H.G.van Paradijs J.Hasinger G.,Jain A.Pietsch W.Truemper J.CDS1997https://cds.unistra.fr/vizier-org/licences_vizier.htmlCDS support team <cds-question@unistra.fr>DatasetAstroObjectsastronomy