TITLE:

Deep U B V R I Photometric Calibration of High Latitude
Fields: SA 57 (1307 + 30) and Hercules (1720+50)

AUTHORS: 

Majewski, S. R., Kron, R. G., Koo, D. C., Bershady,
M. A.

PUBLISHED: 1994, PASP, 108, 1258

ABSTRACT:

We present CCD photometric calibration sequences in the
magnitude range V = 17-22 for two fields at high
Galactic latitude: SA 57 (at the North Galactic Pole)
and Hercules (l=77, b=35). Photometry to a precision of
about 0.02 magnitudes at V=20 and, in general, better
than 0.1 magnitudes at V=22 was obtained in the Johnson
UBV as well as the Kron-Cousins R and I bands. These
data are suitable for setting magnitude zero-points in
catalogues of faint stars, galaxies, and QSOs, and we
apply them to our own photographic catalogues in these
two fields.