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Entering transform data from overlapping pair of filters

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CrossoverManiac
Affiliation
American Association of Variable Star Observers (AAVSO)
Mon, 07/06/2020 - 01:57

I took measurements of EE Cep using the B,V, and I photometric filters and perform a transform with the B-V and V-I.  I received two different results for the magnitude of the target star in the V filter (10.809 and 10.825).  I would like to ask which one should I delete and should I then delete the measurement from the other filter in the transform?

bskiff
Affiliation
American Association of Variable Star Observers (AAVSO)
Mon, 07/06/2020 - 02:54
Entering transform data from overlapping pair of filters

The rather modest difference here is actually giving you some idea of the uncertainty on the transformation itself combined with errors in the measurement of the variable.  There will be some uncertainty in the magnitudes and color-indices of whatever you are using for standards, too.  The mean of your two measurements has a notional rms scatter of 0.011 mag, which a lot of folks would be happy with.

\Brian