; BSCOR ;--------------------------------------------------------------- ;! Combines two beam-switched images ;# TASK ANALYSIS SINGLEDISH OOP ;----------------------------------------------------------------------- ;; Copyright (C) 1996-1997, 1999 ;; Associated Universities, Inc. Washington DC, USA. ;; Eric W. Greisen ;; ;; This program is free software; you can redistribute it and/or ;; modify it under the terms of the GNU General Public License as ;; published by the Free Software Foundation; either version 2 of ;; the License, or (at your option) any later version. ;; ;; This program is distributed in the hope that it will be useful, ;; but WITHOUT ANY WARRANTY; without even the implied warranty of ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the ;; GNU General Public License for more details. ;; ;; You should have received a copy of the GNU General Public ;; License along with this program; if not, write to the Free ;; Software Foundation, Inc., 675 Massachusetts Ave, Cambridge, ;; MA 02139, USA. ;; ;; Correspondence concerning AIPS should be addressed as follows: ;; Internet email: aipsmail@nrao.edu. ;; Postal address: AIPS Project Office ;; National Radio Astronomy Observatory ;; 520 Edgemont Road ;; Charlottesville, VA 22903-2475 USA ;----------------------------------------------------------------------- BSCOR LLLLLLLLLLLLUUUUUUUUUUUU CCCCCCCCCCCCCCCCCCCCCCCCCCCCC BSCOR Combines beam-switched images INNAME Input "plus" beam name INCLASS Input "plus" beam class INSEQ 0.0 9999.0 Input "plus" beam seq. # INDISK 0.0 9.0 Input "plus" beam disk # IN2NAME Cutoff "minus" beam name IN2CLASS Cutoff "minus" beam class IN2SEQ 0.0 9999.0 Cutoff "minus" beam seq. # IN2DISK 0.0 9.0 Cutoff "minus" beam disk # OUTNAME Output image name (name) OUTCLASS Output image name (class) OUTSEQ -1.0 9999.0 Output image name (seq. #) OUTDISK 0.0 9.0 Output image disk unit #. BLC Bottom left corner of input TRC Top right corner of input FACTOR Correct the beam throws by multiplying by FACTOR ORDER Baseline order (0 or 1) DPARM Parameters: (see HELP) (1) scale factor plus image over minus (0 -> 1) (2) > 0 => apply scale before differencing, else apply scale with convolution (3-4) x-pixel baseline region 1 for both images (5-6) x-pixel baseline region 2 for both images DOALIGN How closely coordinates agree ---------------------------------------------------------------- BSCOR Task: Combines the two images of beam-switched data. A constant baseline is fit to two windows in each row and subtracted from that row. Then (optionally) the plus image is scaled with respect to the minus image. The two are then differenced and convolved with a one-dimensional function on a row by row basis to combine the two images. Adverbs: INNAME.....Input plus beam image name. Standard defaults. INCLASS....Input plus beam image class. Standard defaults. INSEQ......Input plus beam image seq. #. 0 => highest. INDISK.....Disk drive # of plus beam image. 0 => any. IN2NAME....Input minus beam image name. ' ' => INNAME IN2CLASS...Input minus beam image class. ' ' => INCLASS (with + -> -) IN2SEQ.....Input minus beam image seq. #. 0 => INSEQ IN2DISK....Disk drive # of minus beam image. 0 => INDISK OUTNAME....Output image name (name). Standard defaults. OUTCLASS...Output image name (class). Standard defaults. OUTSEQ.....Output image name (seq. #). Standard defaults. OUTDISK....Disk drive # of output image. 0 => highest number with sufficient space. BLC........Bottom right corner in input image of desired subimage. Default is entire image. TRC........Top right corner in input image of desired subimage. Default is entire image. FACTOR.....Change the beam throws by FACTOR. ORDER......Order of baseline removed from each row of each image. Only 0 and 1 are allowed. DPARM......Parameters: (1) The plus beam may be scaled by DPARM(1) wrt the minus beam. (You may need to use IMFIT to determine this ratio. Be sure to fit a baseline as well as a Gaussian.) 0 => 1. (2) The ratio may be applied at two different stages: if DPARM(2) > 0, the images are scaled before they are differenced. Otherwise, the scaling is done through a modification of the convolution function. (3) Start x pixel of both images to use for the first of 2 baseline regions. 0 => 1. N.B. this applies after BLC(1) has been applied. (4) End x pixel of both images to use for first baseline region. 0 => all (not a good default). N.B. above N.B. (5) Start x pixel of both images to use for the second of 2 baseline regions. 0 => none. N.B. above N.B. (6) End x pixel of both images to use for second baseline region. 0 => all (an okay default). It has been found by experimentation that it is essential to use the same baseline regions for both images. DOALIGN....The alignement of the two images is checked at a level determined by DOALIGN. = 1 => they must agree = 0 => axis 1 must agree, 2 need only be close = -1 => types and dimensions must agree = -2 => only dimensions are checked ----------------------------------------------------------------