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Hi Martin,
The auto-suggest does not come from the BAA website. It is actually your web browser remembering what you have previously entered into those fields and then suggesting options based on this historic input.
It would be difficult to auto-populate object name and location from the filename as we would need to agree a standard filename layout that everyone would need to use, and otherwise gibberish would appear in those fields. There would also be a reasonable amount of bespoke development by BAA volunteers to write code to extract this information from the filename and populate the fields, assuming it is possible.
Sorry it is not better news.
Best wishes,
Andy
Hi Eric,
I am sorry to read that you are unhappy about your posts being publicly visible. While only BAA members can post to the forum, in common with most internet fora and other astronomy fora the posts are visible to all, e.g. SPA, AAVSO, cloudy nights, stargazers lounge, astrobin, etc. This means internet search engines like Google have access to the content, and this can be helpful when searching on a particular topic.
I would draw your attention to the BAA forum terms of use, in particular:
“We strongly advise that you do not disclose personal information to others. Do remember that the Forum and Member Pages are visible not just to BAA members, but to the whole world. If you wish to exchange contact details with other members, the Forum and Member Pages are not an appropriate place to do it.”
https://britastro.org/forum-terms
Kind regards,
Andy Wilson
BAA Systems Administrator & Web Content Editor
Alex & Nick,
You can send me the pdf’s if you want. I can create an Armagh 2019 meeting page in the Publications -> Downloads -> Past Talks area of the website.
Best wishes,
Andy
Hi Dave,
Roger has decided to step down after 20 years of excellent service as Director of the VSS. A long service for any Section Director!
It is all explained in the past few VSS Circulars where Roger announced he would be standing down. We are very fortunate that Jeremy Shears agreed to take over from 1st September.
https://britastro.org/downloads/14108
Also note that Roger is not disappearing from the VSS as he will continue on as Assistant Director. From personal experience I know how busy the VSS can be so I am sure Jeremy will appreciate the help.
Best wishes,
Andy
A tweak has been made to that webpage, so the Photometry forum is now included. It was due to an oddity in how Drupal works, meaning this forum had to be manually added.
Andy
Well spotted Eliot!
I have done a quick test moving the post between forums and I think you are correct as to the cause. I have notified the BAA Website Developer so he can investigate.
Cheers,
Andy
I understand the following eBulletin on John Wall’s cremation was not received by everyone who knew him, so I repeat it below.
I’ve just been advised by Joyce Porritt, John Wall’s partner of many
years standing, that he is being cremated next Thursday (27th June) at
12.15 and she thought some of you might like to raise a glass in his
memory?Although, John died in January 2018, he donated his body to Leicester
University and they have only just finished with it! The cremation
will be a small, private affair, organised by the University.Roger Pickard
Hi Martin,
Apologies for the time it has taken to respond. I wanted to run my own tests before replying to be sure I was giving you accurate information.
The quick answer is the enlarge button will show a larger image if the image has been made smaller to fit webpage that shows the image and associated information. Also, large images are not recorded at the original resolution in the website.
The BAA website is built using Drupal. When images are uploaded Drupal will sometimes shrink images and may also reduce the image quality to make the image file smaller. We do not consider the member pages a formal image archive for storing images, rather a place to share observations and other interesting astronomical images. A formal image archive would not compress images, but would be a large project and probably not use Drupal.
I’ve run some tests by uploading a fairly large image of the Astronomical Clock at Exeter Cathedral.
https://britastro.org/node/18461
I created both jpg and png versions of the image, though I have only left the jpg version on the website. The original image is 2008 x 2443 pixels, with the jpg version 1.28 MB and the png 5.66 MB.
After I had uploading both versions I clicked ‘expand image’ and downloaded the new image. Both jpg and png had been resized by Drupal to 1355 x 1648 pixels, with the jpg image being 246 KB and the png 2.61 MB. However, I uploaded the same jpg image twice during this process and the first time Drupal retained the original size of 2008 x 2443 pixels but reduced the image quality so it was only 530 KB.
Note, while I think this is mostly due to how Drupal works, it is possible that different browsers will give different results. I used Google Chrome on a Windows 10 computer for these tests.
Andy (member of the Website Operations Team)
Hi John,
Thanks for pointing this out.
The message about needing to login is a generic message in the ‘Downloads’ area as a lot of the content is only available when BAA members are logged in, for example the full Journal archive dating back to the first Journal in 1890. However, there is some content like the slides from this workshop where the restriction has been lifted.
I’ll add this issue to the list of development items for the website, though I am not sure if it will be possible to remove the message where the restriction has been lifted.
Best wishes,
Andy
P.S. This old message jumped to the top of the list yesterday as it was being used for some website development testing.
In case any spectroscopists have missed the announcements elsewhere, the BAA is holding a 1 day Spectroscopy Software Training Workshop on Saturday 24th August 2019 in Birmingham, UK. It will cover the 2 software packages ISIS and BASS Project. The BASS Project by John Paraskeva (author of the software) and ISIS session will be run by David Boyd.
Thanks to the generous support from both the Equipment & Techniques and Variable Star Sections of the BAA, the cost is only £5 for members of the BAA and £7 for non-members.
More details can be found at the following link:
https://britastro.org/spectro2019
Online bookings can be made at:
https://www.britastro.org/spectro2019booking
To get the most out of the session attendees should bring along a laptop with BASS Project and ISIS installed.
If there is sufficient interest then we hope to run future spectroscopy workshops on other software and topics.
Clear skies!
Andy Wilson (Workshop Organiser)
Hi Eliot,
That is a good looking, easy to use website. It is the kind of thing that should be very useful.
James, do you have any links to the other applications? Then we could add them to the VSS links.
Cheers,
Andy
Hi Jack,
I would be surprised if it was the main mirror that needed adjusting, but it is an easy adjustment to try. There is a screw at the bottom of the LHires III that you can loosen to allow a small movement of the main mirror. The user guide has instructions on how to do this including pictures of the procedure.
Was it definitely the main mirror and not the guide mirror? The user manual also has instructions on how to adjust the guide mirror.
That said, my first place to start would not be the mirrors, but the main collimator lens and guide camera focus, unless you have already tried these adjustments.
You can leave the spectrograph on the telescope to adjust the collimating lens (doublet) focus, in fact this is normal practice. You access the lens via the little doors at the side of the spectrograph. I expect you know how to do this and the easiest way is to focus it using the spectrum of the neon calibration lamp.
I’ve found that the sweet spot for my Lhires III does not have a perfectly thin spectrum height, though others may have tweaked theirs to give better results. There was a long discussion on this topic in the below forum thread.
https://britastro.org/node/15094
Cheers,
Andy
I think that would make the emission region about 250 light years across, assuming a distance of 55 million light years.
Andy
Fascinating spectrum Robin! A good demonstration that the emission lines are generated in the central region of the galaxy.
Cheers
Andy
It is the same for me. I like the camera control functionality of Maxim DL. I got the Sky X later when I needed a more capable planetarium software for my spectroscopy projects. The same goes for PHD2. I was using Maxim for guiding but I found keeping the star on the spectrograph slit hard going, so I tried out PHD2 and have never looked back.
I should add I am using Maxim DL 5, an old version. When I need to change software I may look for cheaper options as I am no longer making use of the image processing functionality of Maxim.
Andy
Hi Eric,
I run a similar setup. Windows 10 with The Sky X, Maxim DL and PHD2 controlling an Astrophysics AP1200 mount. It all works very well. I find Windows 10 very good and stable, other than occasional annoying updates. I think you may be able to prevent updates by setting the internet access as a metered connection, though I am not sure if that still works. I tend to spot updates before hand as they will usually happen on my indoors PC first, and then run the update in the daytime.
Cheers,
Andy
Hi David,
I know a bit about this but I would not call myself an expert.
There are a couple of important points to consider relating to the type of variable star.
First, if all you are interested in is timing, like eclipsing binaries, or detecting the outburst from an object, then a TG filter really should not matter.
When submitting observations to be compared with V filters, if the star has strong emission line features in the spectrum, then I think this can lead to larger differences between a TG and a V filter.
There is an option to submit TG filter observations in the BAA Photometry Database.
Cheers,
Andy
Robin, congratulations on contributing to the debate! I would be surprised if varying the mass for the explosion in a 2 WD merger scenario did not lead to a variation in luminosity, though maybe the mass range is not significant. I thought there was a lack of good quality measures to any great distance where Type Ia’s are used, but I must admit that I’ve not looked into this in great detail.
Andrew, I think there might be difficulties in getting supernova explosions in core collapse supernova models but not a WD that reaches the Chandrasekha mass limit. I have a recollection of reading somewhere in the past couple of years that modelling revealed that certain stellar mass ranges could lead to explosions while others may collapse to a black hole without creating a supernova.
Cheers,
Andy
I only saw then end of the program so I am not sure if they mentioned this as a possible cause.
The standard theory is that Type Ia supernova are all about the same luminosity as they are caused by the explosion of a white dwarf when it reaches the Chandrasekha mass limit. This holds true if matter is slowly added to the white dwarf so that it goes bang at exactly Chandrasekha mass. Hence a standard mass for the explosion, a standard luminosity, and so you can work out how far away it is.
I’ve heard of the possibility that you could also get a Type Ia supernova by the merger of two white dwarfs. They could have various masses, so the mass and luminosity of a Type Ia would not be a set value. This would cause problems with the determination of the Hubble Constant using this approach. I am not sure if this has now been discounted, or something that is quietly overlooked.
Andy
