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Another HADS star from the study Dave has introduced to me - new V filter in place now as well. GSC 03004-00870 in UMa.
Quite a non-descript field, and had to again go hunting for reference stars using the APASS v9 photometric catalogue - everything here is over magnitude 12... Curve looks OK - instrumental flux steadily dropped throughout the evening - suspect I might have had a little misting of mirrors, but good enough for the result. I must connect up my secondary dew heater...
A run at capturing V416 UMa this evening, which is a short period HADS (~1.52hrs) - it's a faint one (mag 13.9-14.5 from my results) and I wanted to have a go at using the G filter and see what kind of exposure is required for this kind of magnitude star. (I have a Johnson V but haven't had chance to take the FW apart to install as yet and to refocus the OAG as a result)
I ended up using 120sec exposures - it'll be interesting to see if this is fine enough to use for timing studies (will await feedback...). Using the APASS DR9 figures for the check stars (from VizieR), I get reasonably close figures, so think that the exposures are about right given the lack of brightness for this one - just whether the timing is good enough. (For some reason I can't get the absolute magnitudes out of AIJ to plot - not sure why?)
Shame the clouds rolled in at the end and prevented me from getting the rise back to maximum to complete the whole cycle - I wasn't that far off...! (the points at the end of the run go completely haywire as a result of the decreased and variable flux).