[alma-config] Re: ALMA configurations

[Min Yun]

Hi Dave,

I personally think the uv cell filling factor is an important
metric.  Mark Holdaway has discussed in some of his memos, and
there is a magic number of >= 40% being a good lower limit.
I have heard several arguments against it, mainly along the line of 
the metric should operate on the final image.  Your arguement for
the full UV coverage is fundamentally sound -- the gaps will manifest
themselves in the final image in some non-trivial way.  This is
one single point always brought up in the imaging defect lecture
given by Ron Ekers.  A "complete" uv-coverage in my opinion is 
also a more concrete goal than all the qualitative discussions of 
"interpolations" or "extrapolations" involved in the imaging process.
I hope you will keep bringing this point up for the group.

I know you are busy, but I value opinion -- you are one of the 
best sanity test persons I know.  Thanks.



					-- Min


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> From: "David Woody" <dwoody at caltech.edu>
> To: "Min Yun" <myun at zia.aoc.NRAO.EDU>
> Subject: Re: ALMA configurations
> Date: Fri, 4 Feb 2000 14:01:31 -0800
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> Hi Min
> As you may have guessed, I have been very busy and have not been following
> the
> configuration discussions.  My main concern is that not enough weight has
> been
> given to the simple evaluation metric of the percentage of the UV-plane that
> is
> covered in a particular configuration or set of configurations.  I put this
> forward
> in memo 270 and believe it is still a viable point of view .  Has this
> been discussed and if so has it been rejected?
> Cheers
> *****************************************************
> | David Woody
> | Assistant Director of Instrumentation
> | Owens Valley Radio Observatory
> | California Institute of Technology
> | 100 Leighton Lane (PO Box 968)
> | Big Pine, CA 93513
> | 760-938-2075ext111, FAX 760-938-2075
> | dwoody at caltech.edu
> *****************************************************
>