[OBSERVATION]Observation data model/comments/Resolution...

[Mireille Louys]

Jonathan McDowell wrote:

>

Hi Martin, I all,

>
> I'd like to ask Mireille to comment on the following which I think
> apply to her diagrams:
>
> >
> >     2) If Resolution and Precision really might 'belong to' many different
> > Characterisations, we need to make sure they are immutable.

what is this ? a kind of constant value? sorry , not clear to me .

> On the other
> > hand, we could say one Resolution/Precision instance can only belong to one
> > Characterisation which might be neater and seems more correct somehow -

It is the case I think, for images at least . The Observed image have
Characterisation descriptors , among them
a Resolution component, a SamplePrecision component that are determined by:
the instrumental chain and the data reduction pipeline.
If a new reduction algo is developped, a new Observation will be produced with
updated values for Characterisation compents.
For a spectrum, this is probably the same situation.
For a list of extracted sources , we have to check.


>
> > presumably Characteristics normally have different resolutions?
> >     3) Is ObservingConfiguration itself the ObsEltList?  What benefits do we
> > get from having a separate List?
> >

I can hook another Object: "Ambient conditions " for example under
ObservingConfiguration,
that can describe the instrumental parameters values for this  Observation shot.
There could be more informations to store than just the list of elements.

cheers, mireille.


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 Mireille LOUYS                 mailto:Mireille.Louys at astro.u-strasbg.fr

 L S I I T                              Observatoire de Strasbourg
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