Affiliation
British Astronomical Association, Variable Star Section (BAA-VSS)
Tue, 02/06/2024 - 20:53
I was trying to add a few brighter targets to my programme.
X Per, BU Tau, AB Aur, CH Cyg, P Cyg
VPhot is not picking up very many comps and especially missing the bright ones. They are there clear and bright on the image but VPot fails to recognise them.
Other faint charts suffer from this too with comps not being recognised.
Is there a way of getting comps from another source?
Kevin:
Share the images to me at MZK. What is your FOV and how does it compare to the VSP chart you may look at?
Note that IF you have a large FOV, VPhot queries the VSP which may itself impose a lower limit on comp magnitudes to include so as not to have too many comps to find.
Ken
I deleted them from…
OK Ken,
I deleted them from VPhot so will upload again in a few days as I'm otherwise engaged for a couple.
Will let you know and answer your questions.
Thanks
Kevin
I have shared 2…
Hello Ken,
I have shared 2 BU Tau images as an example of some targets for which VPhot does not find many (sometimes none) comparison stars.
My FOV is 1.69 x 1.28 deg
Kevin
I see 4 comps brighter than 70 in a 70 minute field
Yesterday all that VPhot detected of AAVSO comp stars for BU Tau was 69, 91 and 93
Today I tried the same image and all it found was 91.
Is there another source of comp stars that VPhot can perform photometry on or anything I can do to improve the number of detected comps?
Right now, I am in a hotel room on Safari, and can log on, but can't do VSP or VPHOT.
Looks like HQ is still ironing out the kinks.
Patience.
Ray