[daip] Some oddities from IMAGR

Craig Walker cwalker at nrao.edu
Sat Jun 21 18:00:53 EDT 2014


I don't see anything wrong with the images, but I'm seeing some strange 
spewings to the terminal from IMAGR.  The data set is a simple VLBA
2 Gbps set with the RDBE PFB at 6cm.  There are just under 200000 vis.
I'm using a SPLIT output with averaging across channels in an IF, but
not across each of the 8 IFs.

IMAGR1: Task IMAGR  (release of 31DEC14) begins
IMAGR1: UVGET: Using flag table version   2 to edit data
IMAGR1: Create J1504+1029  .UVWORK.  26 (UV)  on disk  3  cno   78
IMAGR1: Beginning channel    1 through    1 with  8 IFs
IMAGR1: IMACPY: found     1528956. of     1574800. possible channels
IMAGR1: IMACPY: average frequency is then   4980.354 MHz
IMAGR1: IMACPY: Copied   196850 visibilities to be imaged
IMAGR1: QINIT: did a GET  of      5120 Kwords, OFF   17454778945611

The number of channels looks goofy, but I guess it is about the
number of vis times the number of IFs (8).  Maybe that's ok.
What does the QINIT line refer to?

The image header has the following.  Check WTNOISE and SUMTIN.  Are they 
reasonable?  They seem suspicious:

AIPS 1: Rest freq      0.000         Vel type: OPTICAL wrt YOU
AIPS 1: Alt ref. value  0.00000E+00  wrt pixel    0.00
AIPS 1: Maximum version number of extension files of type CC is   1
AIPS 1: Maximum version number of extension files of type CG is   1
AIPS 1: Maximum version number of extension files of type HI is   1
AIPS 1: Maximum version number of extension files of type PL is   1
AIPS 1: Keyword = 'WTNOISE '  value =  5.429538E+15
AIPS 1: Keyword = 'SUMWTIN '  value =  1.690504E+11
AIPS 1: Keyword = 'CCFLUX  '  value =  7.614199E-01

This is on my work machine so you could access the data fairly easily
(noatak, user 332).

Cheers,

Craig

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