SPM 2.0 CCD Photometry
In order to calibrate the photographic photometry, a number of CCD frames were obtained using the 0.9-m and YALO 1-m telescopes at CTIO, with standard sets of B and V filters. The reduced CCD photometry for stars which were also measurable on the SPM plates is given in a file separate from the main Catalog. This file, spm_2_0.ccd, contains 7783 stars, for which the magnitude distribution in V and B is shown above.