[daip] DOUVCMP

[Eric Greisen]

Lawrence Rudnick writes:
 > i understand from low freq tutorial that FILLM should be
 > run with DOUVCMP -1, in order to preserve weights.
 > is that true throughout processing, e.g., i now need to
 > do a uvlod.  thanks.

The choice is always yours.  Compressed data carry one weight for each
antenna-pair/time, i.e. one weight for all polarizations, IFs and
spectral channels of that antenna pair at that time.  If you have only
1 IF this is probably not important since weights do not vary with
spectral channel.  However, if you have multiple IFs then weights do
vary a lot with IF and proper weights are significant in imaging.

Eric Greisen