[evlatests] UVW fixed; new archive revision number

Walter Brisken wbrisken at nrao.edu
Thu Jul 5 16:01:17 EDT 2007


I think the reason left to run UVFIX is if one wants to put new 
observations in a similar frame to those of old observations.  Calc 
certainly supercedes UVFIX's precision.  There are some details left to 
get right though...

-W


On Thu, 5 Jul 2007, Eric Greisen wrote:

> Ed Fomalont writes:
> > Hi Walter,
> >
> >     Thanks for the fix.  A related three part question.  People often
> > run UVFIX anyway (not for the sign problem over the last few days) to 1)
> > correct for the old VLA time error of 0.5 sample; 2) increase the
> > accuracy of the u,v,w that are computed by the on-line system; 3)
> > correct for the field stretching associated with annual aberration.  Are
> > any or all of these previous minor 'errors' now corrected with the
> > on-line uvw and times by mod-comp free, or should UVFIX be run for the
> > wide-field high-precision work anyway?
> >
> >     Ed
>
> The format still has the end time - but there has been no reason for
> FILLM to regard that as gospel.  Do you have any idea why we have kept
> that absurdity for so long?  I am about to put back a new FILLM
> that corrects the time by half the integration time.  All data of any
> obs date will be correct henceforth.  The issue is documenting this
> change.  I don't know about reason 2 even with ModComps...
>
> Eric
>



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