Total magnitudes of Virgo galaxies. 1. Construction of a self-consistent reference dataset spanning 8th to 18th magnitude

The main objectives of this series of papers are: (1) to demonstrate the ex istence of serious mutual disagreements between established total (and othe r integrated) magnitude scales for Virgo galaxies; (2) to attempt to quanti fy both the systematic and random errors present within these magnitude sca les; (3) to investigate the origins of any large error uncovered; arid ther eby (4) to encourage the general adoption of rigorous total-magnitude measu rement procedures by the astronomical community. The ramifications of the f indings presented in this series of papers will be discussed in detail at a later date. In this paper, the first in the series, a self-consistent dataset of trustw orthy total-magnitude measurements is compiled for a sample of Virgo galaxi es spanning a range of 10 000 in apparent brightness, based on only the mos t reliable measurements and photometry currently available. This reference dataset, which includes luminosity profile shape information, will be used in subsequent papers as one of the bases for assessing existing magnitude s cales for Virgo galaxies. As most published magnitudes are based on B-band observations, this series of papers will also focus primarily on B-band mea surements.