<?xml version="1.0" encoding="UTF-8"?>
<?xml-stylesheet type="text/xsl" ?>
<casaxml xmlns="http://casa.nrao.edu/schema/psetTypes.html"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://casa.nrao.edu/schema/casa.xsd
file:///opt/casa/code/xmlcasa/xml/casa.xsd">
<task type="function" name="feather" category="imaging">
<shortdescription>Combine two images using their Fourier transforms</shortdescription>
This task can be used as one method of combining single-dish and
interferometric images after they have been separately made.
The algorithm converts each image to the gridded visibility plane,
combines them, and reconverts them into an combined image. Each image
must include a well-defined beam shape (clean beam) in order for
feathering to work well. The two images must have the same flux
density normalization scale.
<param type="string" name="imagename">
<shortdescription>Name of output feathered image</shortdescription>
<description>Name of output feathered image
Example: imagename='orion_combined.im'
<param type="string" name="highres" mustexist="true">
<shortdescription>Name of high resolution (interferometer) image</shortdescription>
<description>Name of high resolution (interferometer) image
Example: imagename='orion_vla.im'
<param type="string" name="lowres" mustexist="true">
<shortdescription>Name of low resolution (single dish) image</shortdescription>
<description>Name of low resolution (single dish) image
Example: imagename='orion_gbt.im'
<param type="double" name="sdfactor">
<shortdescription>Scale factor to apply to Single Dish image</shortdescription>
<description>Value by which to scale the Single Dish image.
Basically modifying the flux scale of the SD image
<param type="double" name="effdishdiam">
<shortdescription>New effective SingleDish diameter to use in m</shortdescription>
<description>New effective SingleDish diameter to use in m
Default: -1.0 (leave as is)
Obviously one can only reduce the dish
effective dish diameter in feathering.