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Publishing interim lists of nominees is an interesting idea. I have my doubts it would encourage many additional people to stand, but you never know.
As pointed out by James, the cost of the election is likely to be the same whether there is one or many more candidates than positions to be filled. If we find ourselves in a position where the number of nominees matches the number of positions for each role, then it would be sensible to consider whether an election should be held.
Looking back over recent ballots, only one person has stood for each of the key Officer roles. However, until the last couple of years there have been more members standing than there were positions to fill for both the Trustees and Council. In 2021 there were 6 members standing for the 5 Trustee positions. Going back to 2018 there were 10 candidates for the 5 Trustee positions and 14 for the 5 Council positions.
Combined with a lack of a volunteer to stand as the Meetings Secretary, this is a concerning decline in members standing for Council, Trustee and Officer positions. I wonder if this could be related to the lack of opportunities for informal chats at events during the pandemic, or if this is due to other factors that will continue the trend.
A final thought. It would be great to include any suggestions and concerns in the latest BAA survey. I have already used it to give some anonymous suggestions.
https://britastro.org/2023/help-shape-the-future-of-our-association
Andy
Thanks for the heads up Bill.
My plan is to travel up the day before. Fingers crossed there will be still be some trains running on Friday.
Andy
Hi Kevin,
A field flattener should work fine for photometry. There is a chance it might improve your photometry if it reduces any distortions in stars towards the edge of your field of view. Though the effect is probably going to be negligible.
If it is the one on the FLO website, then it also acts as a x0.8 focal reducer, so your focal length goes from 540mm (f/6) to 432mm (f/4.8). It would be a good idea to check the sky pixel size of this setup, though in all probability this will be about whether or not you bin the pixels.
Cheers,
AndyHi Kevin,
You are right to be wary of using a light pollution filter for photometry. These filters are designed to help imaging nebula.
Looking at the specification it has high transmission in the nebula emission lines and blocks common narrow band light pollution. In photometry, the magnitude you measure depends on which part of the spectrum you observe. So the magnitude measured through a filter like this could not be compared with other observers.
If you are just measuring the period of a variable target or looking for outbursts then this might be usable, but it may introduce problems.
Another point to consider, these filters are designed to boost contrast of targets that predominantly emit light in the nebula lines. This is unlikely to be much use for stars or asteroids as they tend to emit across the visible spectrum.
Best wishes,
AndyHi Paul,
Thanks for letting us know. I will contact Hazel to see if we will email everyone who has booked a ticket.
The BAA Meetings Secretary, Hazel Collett, found out all of the accommodation had been booked in June. Unfortunately they did not reserve it for our meeting, so it had been quickly booked up by other people.
We updated the meeting page with a suggestion of nearby accommodation. https://britastro.org/event/autumn-2023
Best wishes,
AndyIt is difficult to choose an ideal telescope as it depends on so many factors. I think you may be considering Deep Sky imaging, which has similar requirements to variable star photometry and comet imaging. While planetary imaging has different needs.
I would say good quality optics of a variety of designs can produce excellent deep sky images. If you want top quality results, then put quality before aperture within your budget.
A key point is ensuring you have a good quality mount that can robustly support the telescope and track well, or receive guider commands to correct for tracking errors. With smaller telescopes, such as small short focus refractors, you can get away with a much smaller and cheaper mount. As you go to larger telescopes and longer focal lengths, the cost of the mount will go up dramatically.
It is also important to have a focuser that can support the camera, as well as any filters or an off-axis guide camera if used.
For starting out with imaging I would recomend a short focus refractor. However, something like an 8-inch SCT on a sturdy mount is a great all round telescope. With available accessories that can be used for both deep sky and planetary imaging.Hi Ken,
This is a bug with the website. I have just reported this to the website developer and I will let you know when it has been fixed.
Best wishes,
AndyHi Michael,
You can see the prices for the different types of membership at this link:
https://britastro.org/join
The rate that would apply to you would be Ordinary Digital, £32.50.
To alter your membership type you can call (0207 734 4145 10am-4pm Mon-Fri) or email (office@britastro.org) the Office. They can update your renewal membership type, or you can renew to the new type over the phone. If they update your renewal membership type, then when you press the renew button in Sheep you will see your new membership type and price.
Best wishes,
AndyHi David,
I have just approved one of the posts and deleted the duplicate.
It is difficult to know why it was classed as spam, but it could be to do with the “provided funds” text, given all the requests for funds scams out there. Though if this post gets approved then perhaps not..
Best wishes,
AndyHi Gordon,
There are no silly questions 🙂
For those who have joined in the past few years, your subscription becomes due on the day of the year you joined. For those who joined many years ago, the annual subscription always ran from 1st August to 31st July the next year.
Reminder emails are sent to every member who has provided an email address, about 95% of members. Those who have not given an email address are sent letters. The reminder emails are sent before the renewal is due, then several after payment was due if the member has not renewed.
Gordon, you can login to SheepCRM to see your renewal date. If you are not logged into the BAA website then click:
Login -> Renew Membership
If you are logged into the BAA website then:
Account -> My membership
You use the same password that you use for the BAA website but you have to login separately to SheepCRM.
I won’t give out specific details on the forum, but Gordon’s subscription is not due for a few months.
Best wishes,
Andy (BAA Systems Manager)The meeting recording has now gone live on the BAA YouTube channel. If you watch it directly on YouTube then you will be able to jump to each of the talks using the time links in the event description.
https://youtu.be/9vNO2gI3RVA
Unfortunately the slides are not properly displayed on the recording until 15 minutes into the meeting. We were hoping to have this fixed but unfortunately it has not proved to be possible.
Best wishes,
AndyHi Ian,
I am glad that did the trick.
Yes, there is no way you can tell that is from two telescopes. Shows excellent agreement between the setups.
Cheers,
AndyIt is a bit hidden away. When you are logged in, navigate to the forum home page. Next to create new message is personal messages.
https://britastro.org/community/forum/personal-messages
It can also be a little tricky to find some people depending on the name they have used.
Making this more accessible and easy to use, is on the list of things to do to the website.
Andy
Hi Ian,
I have implemented a change to the BAA Photometry Database that should resolve this problem.
The upload now checks the Julian date, object, observer id, filter (visual observations are automatically recorded as no filter), location and instrument.
This does mean it is just a little easier to upload duplicate observations, especially as the instrument and location are free format fields. However, it should be rare that someone comes back to upload observations at a later date but with very slightly different entries for these fields.
I should add that while I have tested this for a variety of scenarios, I can’t check all possible scenarios. Hopefully it won’t cause problems for other observers. There is a chance it has slowed down the upload processing, but hopefully any impact will not be noticeable.
One final thought. For an observation to be flagged as a duplicate, the Julian dates must be coincident in time to better than a tenth of a second. That is certainly possible, but I thought I’d mention it as my expectation would be for a few seconds or tenths of seconds between the timing of images with different setups, with just a few occasions where they agree to better than a tenth of a second.
Best wishes,
AndyHi Ian,
Yes, I manage the BAA Photometry Database. You can contact me here and also at my email address.
When I created the online database I did not foresee a single observer submitting observations of the same star in the same filter made at the same time from different locations or telescopes. The previous offline database had a problem with duplicated and even multiple sets of the same observations, so it seemed a good idea to prevent duplicates being added. I have heard of this doing the job correctly in the past but this is the first time for this scenario where it creates a problem.
I will need to give this a little bit of thought and remind myself of the precise details of the database and the code that performs the checks. The location and telescope were not historically populated for all data. They were designed as descriptive fields and are not built into the checks to prevent duplicates. It may be possible to make a tweak, so one or both of these are included in future checks but I need to spend a little time checking into this before implementing any changes.
There is a simple fix, which is to provide you with two observer codes and logins. The observer logins are tied to a single observer code, and the observer code is one of the key fields used by the duplicate check. This would not be as neat a solution, as it would split your observations into two observers. So it is probably worth giving this a few days as I may be able to easily make a change to the duplicate check.
Best wishes,
AndyI suspect the drop in the blue magnitude is due to the material cooling as the ejecta of the supernova expands. Taking a first approximation of a black body, then the shorter frequency blue light will reduce first as the explosion cools. You can see the effect in Robin’s spectra animation from a few days ago.
With the caveat that I am not an expert on supernova, so someone else may be able to jump in to confirm or refute this notion.
AndyApologies to Nick, I accidentally deleted his light curve of SN 2023ixf. Now added back after Nick sent me a copy.
As an admin I have delete and detach links, next to the link to view attachments. I must have hit one of those when trying to view his light curve.
It is great seeing all the photometry and spectroscopy of this supernova.
Andy
Hi,
How do you calculate its magnitude please ?Hi Kwong,
A variety of software packages can do photometry, including some image processing packages such as MaxIm DL. If the software you are already using doesn’t have the ability to calculate magnitudes, then I would opt for a free package that is easy to use, unless you are sure you will get into photometry of variable stars, exoplanets or asteroids.
There is a list of some software packages at the top of this page on submitting to the BAA Photometry database.
https://britastro.org/vssdb/notes_submissions.php
I’ve not tried them all, but MuniPack might be the easiest to get started with.
The trick is you have to measure the magnitude of the target star (the supernova) as well as several comparison stars. The comparison stars need to be carefully chosen, to avoid variable stars and to ensure they themselves have a robust magnitude. The AAVSO chart plotter is the perfect place for this.
The other key point. The supernova and none of the comparison stars must be over exposed as that would cause the calculation to go wrong. A good rule of thumb is for the peak counts in any pixel of those stars should be at most 2/3rds the full well capacity of your camera.
Good luck with your observations.
Andy (BAA Variable Star Section Database Secretary)
Here is a link to the AAVSO chart. For those who haven’t used them before you can adjust the size and orientation by clicking plot other chart, and access the magnitudes of the labelled comparison stars by clicking photometry table for this chart.
https://app.aavso.org/vsp/chart/?star=SN%202023ixf&fov=60&maglimit=14.5&resolution=150&north=up&east=left
Andy
