[evlatests] Image Rotation by 180 degrees confirmed

[Rick Perley]

    Michael observed Cygnus A on Saturday night with both WIDAR and the 
VLA, using exactly the same file.   He placed the phase center near the 
middle of one lobe, so as to more easily determine if we have a problem 
with our phase conventions, as some earlier observations have suggested. 

    I have made images of the 6cm data from both the VLA and WIDAR 
correlator data.  The two databases were calibrated in identical 
manners.  There is no question whatever that the WIDAR image is rotated 
by 180 degrees about the phase tracking center.  So (in effect) the 
WIDAR baselines 'point' the wrong way.