[daip] IMAGR

[Leonia Kogan]

Ian,

you wrote:

>If I do use multiple fields, 
>then the central source is going to be present in all the fields (assuming we 
>have NFIELDS as a power of 2, so would this be a problem ?

If you use multiple fields (NFIELDS>1) then the center of each field and 
their sizes are determined by RASHIFT, DECSHIFT and FIELDSIZE.

Properly chosing these adverbs you can achive not overlapping fields and 
the central source will not present in all the fields.

Leonia



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>From daip-admin at donar.cv.nrao.edu Tue May 21 08:12 MDT 2002
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Date: Tue, 21 May 2002 10:12:56 +0100 (BST)
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Hi,

I'm a little confused over how best to CLEAN. I have a single field (A config 
VLA) which is thus ~9x9 arc-min. There are a few sources at ~1mJy/beam, and 
everything else is ~ 100 mJy/beam. All the sources are either un-resolved or 
partially resolved. One of the brighest sources lies at the centre of the field 
(we chose this target to be at the centre in the proposal). What would you 
suggest as a good procedure to CLEAN using IMAGR. Would multiple fields 
(NFIELDS) be best, or would a single field suffice? If I do use multiple fields, 
then the central source is going to be present in all the fields (assuming we 
have NFIELDS as a power of 2, so would this be a problem ?

I realise that it may be difficult for you to answer this, but any hints/tips 
would be greatly appreciated.


Regards,

Ian Pattison




::::::::::::::::::::::::::::::::::::::::::::::::
::                                            ::
::               Ian Pattison                 ::
::                                            ::
::Department of Physics & Astronomy           ::
::University of Leeds                         ::
::LS2 9JT                                     ::
::United Kingdom                              ::
::                                            ::
::Tel: +44 (0)113 2333872                     ::
::email: ip at ast.leeds.ac.uk                   ::
::WWW: http://ast.leeds.ac.uk/~ip             ::
::                                            ::
::::::::::::::::::::::::::::::::::::::::::::::::



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