[alma-config] simulations and metrics

[Tamara Helfer]

Hi Mel,

measure=cornwell is the same as cornwell's "maximum emptiness",
which is a lot more like CLEAN than like maximum entropy.
For real (BIMA SONG) data, I get comparable results with CLEAN and 
maximum emptiness.  We're using MOSSDI (a Steer-Ito-Dewdney clean) for
BIMA SONG data since maxen was diverging in the total flux.  For my
simulations, which are noise-free, maxen doesn't have this problem.
And maxen tends to recover more flux than the standard clean
(though not more than multiscale clean) for data without total
power included, which is why I was using it for my simulations...

	Tam


On Thu, 20 Jan 2000, mel wright 456 wrote:

> Hello Tam, Mark, Adrian etal,
> 
> 	MOSMEM 
> Keyword: measure
>          The entropy measure to be used, either "gull" (-p*log(p/e)) or
>          "cornwell" (-log(cosh(p)) -- also called the maximum emptiness
>          criteria).
> 
> measure=cornwell has been giving me nicer results on SgrA mosaic than
> the default measure=gull, despite Bob's comment in the help file:
> "Using the maximum emptiness criteria is not recommended."
> which may be obsolete ?
> 
> 		Melvyn.
>