sn_cormatch
sn_cormatch
tries to determine the position offset and the
magnitude difference between the target and the reference images
by cross correlating the row and column brightnesses.
This procedure is much less reliable than the
fiducial star matching procedure since
it is very susceptible to sky fluctuations.
However, it is valuable for fields in which there are less than
two fiducial stars.
The script first generates a row spectrum of both the target and
reference image by adding all the columns up using the
mash
command.
It then uses the
corrcol
command to determine the cross-correlation between the
two spectra and hence the row offset.
It then does the same for the column spectra of the
target and galaxy.
sn_cormatch
updates the values of the
keywords
NMATCH,
DR,
DC,
MAGDIFF, and MAGDIFF3 into the
.cand file.
Last Updated 2/27/97 -RRT