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Transform Applier - not if Ensemble?

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ldj's picture
Transform Applier - not if Ensemble?

Having just completed my automated ensemble photometry routines, I came to find tha TA does not support ensemble observations.

Is there a technical reason or is it just that it can't been time to support it yet. If it's a technical reason, what data is missing?

--- Dave LDJ

SGEO's picture
Ensembles and transformation


The topic of ensembles and transforms was addressed in some detail in

For TA the issue is that by design it is placed in the data pipeline right between the AEF data file ready for submission and the webobs submission button. At that point there is insufficient information to be able to apply a transformation. The AEF file does not have the details of the stars in the ensemble, neither instrumental nor reference, nor the methodology applied to the stars.

There is also the issue of where the data is going, the AID design. It is not designed to retain the details of any ensemble you applied to the observation. As opposed to using a single comp star which allows a researcher to identify your reference value via the chart reference and expose the instrumental magnitude by backing out the standardization. If that single comp star observation is transformed it is still pretty detailed to dig down to the raw data. But it is possible based on the grouping information put into the record.

So the recommendation is that given the option of using an ensemble or transforming a single comp observation, it is more useful to AID to do the later.


ldj's picture
Thanks for that - I'll need

Thanks for that - I'll need to digest it :-) --- Dave

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