[daip] UVCON/FITS problem

[Eric Greisen]

I have played with UVCON at some level and do not understand what is
happening.

When I run it as you did, then the header passed down to FRQTAB and
beyond is all 0 and of course it fails.

When I run it correctly telling it to use an image, then the header
appears to be okay and it gets further.  However, when it reaches the
imaging/modeling stage it thinks that the largest U or V allowed is 5
10^6 while the data are suppposed to be 3 10^9 or so and thence all
points are discarded.  Oddly, the data are then written out as pure 0
in all parameters rather than 0 only in the data - but in either case
they are not useful.  This happens too with your "good" case if one
forces image rather than Clean components.

When I think about it - 20 milliarcsec cells at such a high frequency
for the VLBA does sound rather strange.  The resolution will be a
small fraction of a milli arc sec.

Leonia and I will look at this some more when he gets back.

Eric Greisen