[daip] Re: question

[Eric Greisen]

Farhad Zadeh writes:

 > First dats set:
 > 
 > AIPS 1: FREQ         3   3.2750000E+08      13.00  9.7656250E+04    0.00
 > 
 > Second data set:
 > 
 > AIPS 1: FREQ         3   3.2666992E+08       1.00  7.8125000E+05    0.00
 > 
 > ewen.p> DBCON1: Task DBCON  (release of 31DEC03) begins
 > ewen.p> DBCON1: Scaling u,v,w of data set 1 by  9.9642176E-01
 > ewen.p> DBCON1: FREQUENCIES DIFFER BY TOO MUCH:  3.26328125E+08 
 > 3.26669922E+08
 > ewen.p> DBCON1: MULTI-FREQUENCY DATA BASES INCOMPATABLE
 > ewen.p> DBCON1: Purports to die of UNNATURAL causes
 > ewen.p> DBCON1: ewen         31DEC03 TST: Cpu=       0.0  Real=       1


When you run IMAGR it wants to correct the uvw from the ref frequency
to the other 2 (in this case) spectral channels.  But that correction
in the one case is 781 kHz and in the other case merely 98 kHz.  These
are too different for the imaging to come out right.

You can run UVCOP in each of the data sets 3 times to make 6 1-channel
data sets and the DBCON them.  The uvw will come out okay that way.

Eric Greisen