[daip] UVMOD/UVFIX question

[Hanno Spreeuw]

Hello Eric, I have posted a UVMOD test on my homepage, please have a look.
http://staff.science.uva.nl/~hspreeuw/
Cheers,
Hanno.

Eric Greisen wrote:
> Hanno Spreeuw wrote:
> 
>> Thank you,
>>
>> It seems that inserted sources with FPOS<>0 do not appear in the 
>> images exactly where they should. The errors increase away from the 
>> tangent point. This confirms earlier results by James Miller-Jones 
>> (CC). However, with FPOS=0, the source always appears at the tangent 
>> point.
>> We are testing new source extraction code. In order to check our 
>> deblending algorithm, we are inserting many sources in a small patch 
>> of the sky. With these artificial sources one always knows the true 
>> flux and position, so that is good for testing.
>> I am considering the workaround with UVFIX for these tests.
> 
> 
> If what you say is true, then it is unlikely for any of AIPS to work 
> correctly.  UVMOD uses the same phasing routines used elsewhere in AIPS 
> including but not limited to UVFIX and IMAGR.  What telescope has 
> produced your data and what are you doing?
> 
> Eric Greisen