REGPIC -- selects regions which define sky and object in a frame.
This routine allows the user to interactively select regions defining
the sky and object. The selection can either be done from a greyscale image
or better, since it is easier to pick up faint stars, by collapsing the
frame along the disperion direction.
Regions which are significantly different from the average should be avoided
since they may be being distorted by other objects on the slit. Try to
choose regions symmetrically about an object and choose the same regions for
standard as well as target stars, even though it may be obvious that the
wings of the standard star spill light into sky regions that looked ok for
your target.
Parameters:
IMAGE -- The frame under analysis
FLAT -- Balance factor frame
DLOAD -- TRUE if dark frame is required.
DARK -- Dark frame representing counts unaffected by slit
profile. This will be subtracted off data before applying
the balance factors.
TRACE -- True if a distortion file is wanted
If TRACE
TRACK -- Name of distortion file. Inside this file will
have been stored dimensions of frame from which
it was generated. These must match those of
IMAGE and FLAT.
REGION -- The output file containing the selected regions.
XSTART,XEND -- X pixel limits of region to be treated.
YSTART,YEND -- Y pixel limits of region to be treated.
GREY -- .TRUE. if greyscale image wanted, .FALSE. for a profile
plot. FALSE is normally recommended because profile plots
are better for spotting contaminating stars etc.
AUTO -- Yes to find scales automatically. Based on going from first
to third quartiles, with some extra knobs and twiddles.
If .NOT.AUTO then set LIMITS
NWIDTH -- If not GREY, a median filter is applied during the collapse;
NWIDTH is its width; NWIDTH = 1 has no effect, but it is very
useful in getting rid of cosmic rays. Must be odd.
DEVICE -- Plot device
METHOD -- Method for selecting regions. C=cursor,T=terminal.
This command belongs to the classes: sky , tilted