The following document lists the file abstract/PHT_CAL_52512003.abs
from catalogue VI/111.
A plain copy of the file
(without headers/trailers) may be downloaded.
A region with low galactic and extragalactic emission is observed near the ecliptic plane. All apertures that have been used by observers during routine observations with a given filter are measured, to obtain the effective area projected on the sky. The results will be compared with the known geometric areas of the field-apertures.