Forum Replies Created
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AuthorPosts
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Jeremy Shears
ParticipantA good start Paul. Hope you get better conditions that will allow you to go a bit deeper on this target.
Jeremy Shears
ParticipantWe can relax now because the BBC has the definitive news item on its website and this object.
Jeremy Shears
ParticipantThanks David. I am glad you are maintaining your catholic tastes in print media. What a crazy article! I always remember Patrick citing Oph as the 13th sign of the zodiac in his debunking of astrology.
BTW, Cornflakes and marmelade was my inclusive short-hand for breakfast, which in my case is “Dorset cereals seriously nutty muesli”, with banana, blueberries, low fat Greek yoghurt, and semi-skimmed milk, but I thought that might sound a bit too bourgeoisie.
Jeremy Shears
ParticipantFourth rebrightening, Gary? It’s hardly out of the stalls, yet!
I think the record holder is EZ Lyn, which showed 11 rebrightenings during its 2006 outburst.
Maybe we should have a VSS sweepstake on how many PQ And will undergo. I’ll say 6, but I hope there are more.
Jeremy Shears
ParticipantNo, not really! Well done Richard! The competition was a great idea Denis. My thinking was that Holmes was infamous for his vitriolic letters which he sent to all and sundry over many years. He rubbed many people up the wrong way through this and I was thinking that Hubble might have been a recipient. But I was obviously barking up the wrong tree!
Great webinar Nick!
Jeremy Shears
ParticipantAn Astronomer’s Telegram, ATel #13776, from the Kyoto group publishes a spectrum taken on June 2. This “showed Balmer absorption lines with emission cores, which are typically seen in dwarf nova outbursts. There are no signals of O III, which were reported in the 1988 outburst”, although they question the 1988 conclusion.
Jeremy Shears
ParticipantI have poor horizons from my obsy, Graeme. But I’m lucky enough to have a second, portable, set up with an AZEQ6 mount which enables me to decamp to more favourable observing locations for special events like this.
Jeremy Shears
ParticipantNice work, Tim! Looks like you solved your problem, but just to say I use V-band comparison star data from the AAVSO VSP. Comps for PQ And are listed here. If you used a V-filter on your camera (which I assume is monochrome?), the resulting mags are quoted as CCD-V. If unfiltered they would be CCD-CV.
Thanks for tackling this star!
Jeremy Shears
ParticipantMy goodness, Robin! You have certainly given this your best efforts. As you say, remarkable that you got anything given the circumstances!
Jeremy Shears
ParticipantGlad you enjoyed the VSS Circular, Daryl.
On the subject of Betelgeuse, we are hoping that Dr Mark Kidger, who wrote about Betelgeuse in this edition and the last one, will speak about the star during a BAA Wednesday webinar. Keep an eye on the webinar listings.
Back numbers of VSSC’s can be accessed here.
Jeremy Shears
ParticipantGood to see people overcoming the odds and securing successful observations of PQ And. I managed to see it this morning at about 02.25 BST. I decamped with my 12 cm refractor to a field a mile away and it’s far too low from my obsy as you can see from the angle of my telescope in the dawn sky.
Jeremy Shears
ParticipantJames, it’s difficult to say as it’s so dependent on your specific set-up, plus we have a brightening sky to contend with. If we are going to extract photometry from images, the star and its comparisons should not be saturated. This will result in shorter exposures than you might normally consider to get a “pretty picture” (but a pretty picture would also be nice as this is such a rare event!). Thus it’s best is to bracket with a range of exposures. Also avoid saving as a file type that compresses the image, like jpg, as that will involve loss of data.
Jeremy Shears
ParticipantMaybe a saw, Robin?
Good luck, though. It would be great to get some spectroscopy.
Jeremy Shears
ParticipantQuite right Nick!
Regarding lunar craters, one cater name after a woman was in honour one of the first women to be admitted to the RAS, Mary Adela Blagg. It is particularly fitting as Mary was an accomplished selenographer who made a significant contribution to standardising the nomenclature of lunar features. She was also a BAA Member.
Jeremy Shears
ParticipantI hope you have copyrighted your surname, David.
Just be careful you don’t fizzle out! Otherwise you might have to change your name by deed poll.
Jeremy Shears
ParticipantHello Roy,
you might like to have a look at James Screech’s BAA Members pages too. For some of his photometry he uses an 80 mm refractor. Also uses an ASI1600MM camera.
Also have a look at Gary’s news article on OJ287. I followed this target with my 100 mm refractor.
Jeremy
Jeremy Shears
ParticipantHello Roy,
following on from Gary’s reply, welcome to the Variable Star Section!
I’m not sure if you already have your kit or you are looking to buy. If you have some already I suggest you start with that.
I used a 100 mm refractor with a CCD camera for several years for photometry of variable stars. I typically took 60 sec exposures, which enabled photometry down to 15th mag, although I could detect stars much fainter than this. I was lucky enough to have a decent mount so unguided exposures were absolutely fine. It also had GOTO so I was able to find targets easily, but not essential.
There is some info about VS CCD targets here.
Most people are using CCD rather than CMOS. Latter can be used, but you have to be careful about calibration as the response of the chip is less linear.
Hope this helps. Happy to answer further q’s.
Jeremy Shears
VSS Director
Jeremy Shears
ParticipantHello Alex,
I understand there was a problem with YouTube streaming this webinar, but as you say it worked on Zoom.
However, should you wish to catch up, the recording is now available on the BAA YouTube channel.
Jeremy
Jeremy Shears
ParticipantI had a similar occurrence earlier, Chris. Using Chrome, when liking an image, I was directed to login, even though I was logged in. I got over it simply by refreshing the page. Maybe that cleared out the cache of previous setting. All has been well since.
Jeremy Shears
ParticipantDid I hear someone mention keys?
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