[daip] Help in imagr

[Eric Greisen]

Oozeer Nadeem wrote:
> Hi again,
> 
> imheader
> ***************
> 
> AIPS 1: Image=1514-241  (UV)         Filename=1514-241    .SPLAT .   1
> AIPS 1: Telescope=GMRT               Receiver=GMRT
> AIPS 1: Observer=CRS                 User #=  121
> AIPS 1: Observ. date=02-AUG-2002     Map date=05-DEC-2008
> AIPS 1: # visibilities     14532     Sort order  TB
> AIPS 1: Rand axes: UU-L-SIN  VV-L-SIN  WW-L-SIN  BASELINE  TIME1
> AIPS 1:            WEIGHT  SCALE
> AIPS 1: ----------------------------------------------------------------
> AIPS 1: Type    Pixels   Coord value     at Pixel     Coord incr   Rotat
> AIPS 1: COMPLEX      1   1.0000000E+00       1.00  1.0000000E+00    0.00
> AIPS 1: STOKES       1  -1.0000000E+00       1.00 -1.0000000E+00    0.00
> AIPS 1: FREQ       110   6.1400000E+08       1.00 -6.2500000E+04    0.00
> AIPS 1: IF           1   1.0000000E+00       1.00  1.0000000E+00    0.00
> AIPS 1: RA           1    15 17 41.995       1.00       3600.000    0.00
> AIPS 1: DEC          1   -24 22 17.793       1.00       3600.000    0.00
> AIPS 1: ----------------------------------------------------------------
> AIPS 1: Coordinate equinox 2000.00
> AIPS 1: Rest freq      0.000         Vel type: RADIO   wrt LSR
> AIPS 1: Alt ref. value  0.00000E+00  wrt pixel    1.00
> AIPS 1: Maximum version number of extension files of type FQ is   1
> AIPS 1: Maximum version number of extension files of type HI is   1
> AIPS 1: Maximum version number of extension files of type AN is   1
> 

You do realize I hope that the way you are running IMAGR will produce an 
image CUBE with 110 spectral channels.  Thus 110 separate Cleans must 
happen.  When you tell IMAGR to stop Cleaning it stops that channel and 
goes on to the next.  That will take a very long time.  If these are not 
observations of a spectral line, then you should set BCHAN and ECHAN to 
encompass only the good channels (the outermost will not be good after 
bandpass correction), then set NCHAV=(ECHAN-BCHAN+1) so that a single 
image is made from the NCHAV channels gridded in the proper place for 
each channel in the UV plane.

Eric Greisen