relative fluxes

[Miguel Cerviño]

Hi, my 2 cnts

> This seems like a viable solution -

I agree :)

> the question is whether this is a problem that needs solving, its  
> contingent priority, and whether we yet have a complete description  
> of the problem.

Yes, it needs solving: ALL theoretical spectra (stellar atmospheres,  
and galaxy models with galaxy mass as
free parameter) have the scale problem (I can develop a more specific  
use case if you want).

> How is this used in the literature?  What fraction of columns/values  
> in VO DBs/images/catalogs require this?  Is there a need to support  
> an offset as well as a scaling factor?

If you work with color (also theoretical) you need the offset (zero  
point) and the scalling factor (solar masses)

> In short, are there domain use cases for this?

I think so... ;)
[Note: there are theoretical models in the VO with this problem, so  
there is some VO used cases...]

It also arrais me an additional question:
Stellar atmosphere models can be described as an Intensity or as an  
Eddington Flux.
The dimensions in both cases are exactly the same, but there are a 4Pi  
factor of difference between
both quantities (an solid angle integral). It can be solved with the  
Sebastien approach?


cheers

	m


-------------------------------------------------------------
"Nunca se debe intentar contentar a
quienes nunca se van a dar por contentos"

                        Javier Marias

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