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0.1.19 deconvolve

Requires:

Synopsis
Image based deconvolver

Description

Several algorithms are available to deconvolve an image with a known psf (dirty beam), or a Gaussian beam. The algorithms available are clark and hogbom clean, a multiscale clean and a mem clean.

NOTE: Recommend using taskname=clean if psf is a dirty beam



Arguments





Inputs

imagename

Input image to deconvolve

allowed:

string

Default:

model

Output image containing deconvolved point model

allowed:

string

Default:

psf

Point spread function (dirty beam)

allowed:

stringArray

Default:

alg

Algorithm to use (clark, hogbom, multiscale, mem)

allowed:

string

Default:

clark

niter

number of iteration in deconvolution process

allowed:

int

Default:

10

gain

CLEAN gain parameter

allowed:

double

Default:

0.1

threshold

mJy

level below which sources will not be deconvolved

allowed:

doublemJy

Default:

0.0

mask

image mask to limit region of deconvolution

allowed:

string

Default:

scales

scale sizes (pixels) to deconvolve

allowed:

intArray

Default:

0310

sigma

mJy

mem parameter: Expected noise in image

allowed:

doublemJy

Default:

0.0

targetflux

Jy

mem parameter: Estimated total flux in image

allowed:

doubleJy

Default:

1.0

prior

mem parameter: prior image for mem search

allowed:

string

Default:

Returns
void

Example

 
 
        Several algorithms are available to deconvolve an image with a  
        known psf (dirty beam), or a Gaussian beam.  The algorithms  
        available are clark and hogbom clean, a multiscale clean and a  
        mem clean.  For more deconvolution control, use clean.  
 
     Keyword arguments:  
     imagename -- Name of input image to be deconvolved  
     model     -- Name of output image containing the clean components  
     psf       -- Name of psf image (dirty beam) to use  
                     example: psf=’casaxmlf.image’ .  
                   If the psf has 3 parameter, then a Gaussian  
             psf is assumed with the values representing  
                     the major , minor and position angle  values  
                     e.g  psf=[’3arcsec’, ’2.5arcsec’, ’10deg’]  
     alg       -- algorithm to use: default = ’clark’  
                       options: clark, hogbom, multiscale or mem.  
     niter     -- Maximum number of iterations  
     gain      -- CLEAN gain parameter; fraction to remove from peak  
     threshold -- Halt deconvolution if the maximum residual image is  
                     below this threshold.  
                     default = ’0.0Jy’  
     mask      -- mask image (same shape as image and psf) to limit region  
                     where deconvoltion is to occur  
 
     ------parameters useful for multiscale only  
     scales     -- in pixel numbers; the size of component to deconvolve.  
                      default value [0,3,10]  
                      recommended sizes are 0 (point), 3 (points per clean beam), and  
                      10 (about a factor of three lower resolution)  
     ------parameters useful for mem only  
     sigma      -- Estimated noise for image  
     targetflux -- Target total flux in image  
     prior      -- Prior image to guide mem  
 
 


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