The Edinburgh-Cape Blue Object Survey - IV. Zone 3: Galactic latitudes-40° > b >-50°

Results for Zone 3 of the Edinburgh-Cape (EC) Blue Object survey are presented. This zone covers that part of the South Galactic Cap between 40 degrees and 50 degrees from the Galactic plane and south of about -12 degrees.3 of declination. EC Zone 3 contains 53 UK Schmidt Telescope fields covering about 1400 deg(2) in which we find some 534 blue objects, including hot subdwarfs (similar to 39 per cent), white dwarfs (similar to 21 per cent), cataclysmic variables (similar to 2 per cent) and some starlike galaxies (similar to 9 per cent). A further 178 cooler stars observed in the survey, including low-metallicity F-and G-type stars, are also listed. Both low-dispersion spectroscopic classification and UBV photometry are presented for almost all of the hot objects and either spectroscopy or photometry (sometimes both) for the cooler ones.