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Preliminary results from a 3h40m run on V799 Aur last night - this is a HADS star with period 1.83 hrs. Autofocus had a slight blip in the middle where there's an 8 min gap or so, but got the period, and the slightly odd shape nicely. AIJ complained about the red ref star - need to check saturation levels on that. These were all 7sec exposures - unflitered exposures need to be so short, even at mag 10.something to stop saturating the stars!

Measurements.png.c9b07e99ea0f5146bc74909c5f88ddda.png

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Wow - that is brilliant and an unusual shape. I wonder if it is multiperiodic although it is not marked as such on the HADS spreadsheet.

With variable stars there is no need to worry about focusing, in fact some defocus slightly to avoid saturation, as long as neighbouring stars don't start to merge.

Congratulations on your first HADS

Dave

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Thanks Dave - yep, I'm less concerned about the autofocus routines now - it can be an issue on this scope if there's significant temp changes, but last night started cold and stayed that way! :D

Very interesting shape, hopefully can contribute this data to the HADS work when I hear from Patrick.

Edited by coatesg

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Why wait, He's already expecting data from you. I usually send the BAA data file. He prefers that you do not submit the data to BAA or AAVSO straight away so that he can do his stuff first. I was advised 3 months but I have only waited a month as otherwise I would forget altogether.

Dave

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    • By coatesg
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    • By coatesg
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