[daip] ZEROSP in IMAGR for spectral line data

[Eric Greisen]

On 07/18/2016 02:47 AM, Karl Menten wrote:
> Hi Eric,
>
> The only way I see to add zero spacing information in IMAGR (using the
> ZEROSP parameter) for spectral line data is that I do it by imaging each
> channel separately with the appropriate value at input. Is this correct
> or is there a more efficient way to do this?
>

Sadly no, there is no better way.  Fortunately MCUBE will gobble all the 
individual images into a cube rather efficiently afterwards.  I suspect 
that we have not encountered all that much use for zero-spacing data in 
continuum or line and so have devoted scant attention to it.  What is 
really important is not the image DC level but the visibilities at 
spacings of  5, 10, 15, and 20 meters.  And we have not measured those. 
although one could deduce some of them from single-dish imaging.

Eric Greisen