I was trying to use astroimagej to create an AAVSO report. The macro requests the “catalog magnitude error” for check and comp star. Where is this found? Sorry, if this is an obvious question but up till now, I’ve been using VPHOT to generate the file and haven’t had to look for this. I didn’t see anything labeled “catalog magnitude error” on the generated plot or photometric report from the plot. Any guidance would be appreciated.
Isn’t the catalog magnitude error the decimal number inside parentheses listed beneath the tabulated standard magnitude in the “Table of Field Photometry”? To make the table, use AAVSO’s Variable Star Plotter. Click the radio button labeled “Photometry.”
Best, Andy
That may be it, but here is a longer winded explanation. I’m actually taking measurements in TR, TG, TB so I don’t see that filter type in any selection as available in the VSP.
However, it looks like there is another err which does show up in the VPHOT processed image overlayed with the comps and targets. If I mouse over, say 121, it will show the magnitude and an error factor and this magnitude and error factor will change based on the filter type. That may be what I’m looking for but I haven’t found any reference specfically to it.
I think that what you are pointing out is indeed what I am looking for. The values that show up in the TR, TG, and TB images in Vphot do match the R, V, and B values.
Thanks very much.
Hi, John,
The catalog values are available only for standard photometric filters (Johnson-Cousins system). B and V are Johnson, Rc is Cousins.
You can approximate that B = TB, V = TG and Rc = TR.
Nikola
Yes, that’s what I have done.