UCD problem in SSA/SpectrumDM

[Francois Bonnarel]

Hi pietr,
I want to answer to one of your statements in a 2 week old message.

>
>>
>> In general I think it is better to classify data by the scientific
>> characteristics (collection, instrument) rather than by the origin
>> (ESO). Just putting up one service for all data at a site is too
>> simplistic.
>>
>
> Does someone from DAL WG have objections against this idea ?
> I have heard arguments that the SSA services list will be to large 
> (e.g. ESO will publish one day all of the spectra from all instruments 
> - many having spectroscopic modes ....)
> Lets make some geneal recommendation in the sense above (or another if 
> justified) and put it in the revised SSA
>
Well I think using the "collection" may help a lot in avoiding too much 
services at a site.
I think to this not only for Spectra but also for images (in the 
perspective of SIA V2).
For an archive storing a couple of very large "missions" we can imagine 
a service for
each mission ( with a single collection). But for an archive a lot of 
Middle size surveys (same Wave band for example) and providing similar 
capabilities it makes sense to have one single service and 
differentiating the various missions by various values of the 
"collection" attribute...

Cheers
Franc,ois

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Franc,ois   Bonnarel           Observatoire Astronomique de Strasbourg
CDS (Centre de donne'es        11, rue de l'Universite'
astronomiques de Strasbourg)  F--67000 Strasbourg (France)

Tel: +33-(0)3 68 85 24 11     WWW: http://cdsweb.u-strasbg.fr/people/fb.html
Fax: +33-(0)3 68 85 24 25     E-mail: francois.bonnarel at astro.unistra.fr
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