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Hi!
Very hazy and thin clouds here yesterday. I captured one frame of UX Boo, but I do not trust the measurement. However, it indicated that it is still bright (my measurement was 11.4 with an error of…. 2.4 magnitudes. So I do not report it. But seems like a somewhat longer peak this time. Hopefully someone else caught it last night – Ian?
Magnus
Hi!
So, another rebrightening!! Last night around 14.5 with C-filter from my windy backyard.
Magnus
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Hi!
A few frames from last night, down to between 15 and 16, Clear filter.
Magnus
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Hi!
I had a falling trend last night, rebrightening seemingly quickly fading, see attachment. Data in the database shortly.
Magnus
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Hi!
Unless there is something seriously off with my routine, I captured it at around magnitude 13 yesterday. Here is a series designed for mag 16 (Clear filter, 5 min exposures).
Magnus
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Hi!
I captured something of a series yesterday night from my backyard. 5 min exposures now and considerable error bars so the movements are possibly noise.
Magnus
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Hi!
Another series from my backyard in Malmö, Sweden. No clear humps here…
Magnus
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Hi!
Yeah, I will! We’re actually two Swedes covering this, me and David Heinonen. It seems that it is possible to identify superhumps already the 12th, although with low amplitude (all the data is in the AAVSO database). Together with Ian’s observations, we should have good coverage, I hope 🙂
Magnus
Hi!
A series from my back yard yesterday (C11, QHY268m, V-filter). Now superhumps are clearly visible, somewhat asymmetrical. Observations submitted to the database and to AAVSO.
Magnus
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Hi!
After re-analyzing the images, carefully examining the images and removing some hit by wind and some other stuff, including increasing the apertures, I get a more smooth graph, and indeed, very small movements, probably mostly noise.
Magnus
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Hi!
A series from my backyard, C11 with a QHY268m camera, clear filter. There are some odd outliers, lower magnitude, that I am in the process of trying to understand (the ref-, check, and compstars all look quite OK-ish), so maybe it will be somewhat adjusted before I submit the observations to the database. Maybe, maybe, a tendency to humps?
Magnus
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Hi!
Managed a few observations between the clouds. Some movements around 12.3 mag in C (clear filter).
Magnus
Hi!
Great, I was quite curious about the quality of that star as well. Or maybe expressed more generally: why and how does reddening matter? OK, the actual spectrum does not match what we would expect – but as long as it is consistent as it is, could that not sufficient for a good ref-star? Just want to understand your reasoning there.
Moreover: I guess it would now also be possible to conclude (at least provisionally) that my problems with responseprofiles was related to the quality of the flat. My thinking in some detail: I use a camera with relatively low dynamic range (8 bits). This makes it challenging to capture the spectrum of a halogen lamp with color tempereature of about 2900 K so that I both get sufficient data in the blue end and avoid saturation in the most intense parts. I solved this now by turning the gain down to 0 (zero), getting maximum dyanmic range (I use a gain of 200 for capturing the faint stars like N Vul 2024 or SS Cyg at quiescence). With that setting, I get around 1400 counts in the lowest end. Previously, with higher gains, I had a count of 3-400. I suppose such low levels cause problems after dark reduction, since I am left with a very low count, very sensitive to low variations in the target spectrum (since I am dividing the target with the very faint flat). Makes sense?
SO I have learned a lot about flat production with these cameras (I have the ASI183mm), I think. Beyond learning more about how I need to check my intended ref-stars.
Magnus
