Two color photometry tool aperture setting

Affiliation
American Association of Variable Star Observers (AAVSO)
Wed, 09/01/2021 - 20:00

In the Two Color Photometry tool we must select a measuring aperture.  One option is Automatic, with radius x.x times FWHM.  

Is this the FWHM of the target, or perhaps the mean FWHM for all the stars used in the measurements (target and comps)?

Phil

Affiliation
American Association of Variable Star Observers (AAVSO)
Multiple Stars

Phil:

Both Two color photometry and time series can use average fwhm of many stars on the image (not sure of the exact number that Geir used but many, probably based on SNR and more than just the target and comp(s)?).

In any case, more than just the target. Enough info for you?

Ken