Forum Replies Created
-
Posts
-
Sonia,
Welcome to your role as the Section Director of the Equipment and Techniques Section.
Best wishes,
AndyHi Sonia,
That is an amazing rainbow! In case you have not found it, there is a BAA Gallery where members can share their pictures. It is a little hidden away under the Observations menu or the ‘Explore’ icon on the homepage.
https://britastro.org/observations/
Best wishes,
AndyAs posts too all the different forums appear in a single list on the front page of the BAA website, I unfortunately doubt that posting to another BAA forum would gain any extra responses.
I have not been doing active spectroscopy with my LHIRES III for a little while, though I used PHD2. I found it very easy and user friendly. It did need a little setup and tweaking, but no more than other software. I would set it up and try it out. Different people prefer different software, so I think it depends on what you find works best for you.
Best wishes,
AndyHi John,
If you are combining errors/uncertainties from individual images then you also need to divide by the square root of the number of images.
A useful check is to calculate the standard deviation on the magnitudes derived from the individual images. This won’t be identical but should not be vastly different. The standard deviation with give you a direct estimate of the random error, and large differences could indicate systematics that are over or under estimated in the formula used to calculate the individual magnitude uncertainties.
Best wishes,
AndyHi John,
In theory stacking the frames or combining the photometric measurements should give similar results as you have found.
With short exposures of 10 seconds, you need to be careful of atmospheric seeing. You might see changes due to atmospheric turbulence from frame to frame.
One option would be to slightly defocus the camera. This will spread the light over more pixels and lower the peak, so you should be able to expose for longer. Obviously you need to avoid blending the light from nearby stars, so you only want a slight defocus.
AndyHi Paul,
Welcome to the BAA!
If you are an active observer, then may I recommend joining one or more of the Observing Sections. You don’t need to be highly skilled to contribute. The Sections will help you to develop your skills and are a great way to get to know other members.
Best wishes,
AndyI am adding to this thread after hearing from Matthew Finch, whose light curve from the BAA VSS Photometry database I showed above. Matthew has seen a significant increase in scatter of his Seestar photometry since late 2025.
Hi Steve,
I will see if I can put you in touch with other BAA members who are using Seestars for photometry. I have taken a quick look at the VSS Photometry Database. Matthew Finch has Seestar observations of T CrB and they not showing the same large scatter as yours, though with less time coverage than your data. The attached plots for the shorter time period from August to November 2025. First showing Matthew’s Seestar data and the second with all the V data in the database as it is better at showing the trend.
Best wishes,
AndyAttachments:
I left my BAA IT role nearly two years ago, so some of what I say may now be out of date.
The BAA is a very low user of Zoom. We rarely use it to broadcast the main meetings, but some Sections use it for online meetings. Most of our main meetings are streamed direct to YouTube. Depending on what you are trying to achieve, YouTube could be a cheaper option as it is free.
Zoom also offer a non-profit license that may be worth exploring for your society.
As mentioned by James, there are others options too. As well as Microsoft Teams and YouTube, Google Meet was excellent the last time I used it, and there are many other virtual meeting providers.
As mentioned by James, the BAA does not have a Zoom account available for members.
We have a small number of licensed Zoom accounts, but the licenses state they are for the sole use of the named individual assigned the license. So we are not allowed to share login details.
James suggests the good alternatives. For the VSS meeting last year, we paid for a 1-month pro license to record the meeting.That is shocking and very sad news. I had known Owen for many years. He was quite a character and could be controversial at times, but to his credit he spoke his mind without worrying what people thought. I remember how he was generous with both his time and sharing his expertise. One of my most memorable astronomical memories is seeing the Veil Nebula through Owen’s large Dobsonian at Kelling Heath sometime in the 2000s. Owen freely gave time to a crowd of people gather round his telescope, effortlessly moving between deep sky targets. He will be sorely missed.
AndyI just realised I was replying to a post from 2015! I was not paying attention this morning.
I can see it came back to the top of the forum as someone is attempting to spam this post. The spam was blocked but the date/time and poster were updated. I shall leave it to the WebOps Team to fully remove the spam and spammer.
Andy
It looks as though Baader do 2″ photometric filters, £171 for the V filter quoted on the FLO website. They are showing out of stock, so you might need to wait for them to order it in, but significantly cheaper than the other options.
https://www.firstlightoptics.com/photometry-filters/baader-ubvri-bessel-photometric-filters.html
I think this has been covered, but unfiltered is definitely preferable to a UVIR blocking filter.
Once you get going, it would be great if you can contribute your observations to the VSS database. I can point you in the direction of different software options to provide the data in one of the upload formats.
Cheers,
Andy (BAAVSS Database Secretary)The wide variety of smart telescopes are great, but as with anything you get what you pay for. Putting together a custom setup where you get a high quality 50mm apochromatic lens, a good quality mount and a good quality CCD or CMOS camera is going to give superior results but will be a lot more expensive. Smart telescopes are designed for convenience and ease of use, and that is where they will beat a custom rig. Also, some smart telescopes like the Seestars and Dwarfs are designed for portability.
You can do science with them, but look into the capabilities to understand the pros and cons. For example, they have colour chips so you can’t just add a photometric filter. Though we already have a couple of observers submitting photometry to the Variable Star Section database taken with Seestars using the green channel from the colour camera. I got myself a Dwarf for its ease of use, portability, and easy access to the fits files and calibration frames.
The resolution will be the same as any traditional telescope with that aperture, focal length and pixel size. You can find results taken with a variety of smart telescopes in the BAA image gallery. Click the images to see the details of the equipment used to find those taken with smart telescopes
https://britastro.org/observations/
You can also search for ‘Seestar’, giving these images.
The best images are obtained by people who do post-processing of the results, rather than relying entirely on the inbuilt processing.
If you want ease of use and portability then they are hard to beat. If you want to extract the maximum science potential then a custom rig is the way to go.
Andy
That is such sad news and a great loss. Over the years I was fortunate to attend several talks by Allan. He talked with authority provided by his deep knowledge of history combined with an entertaining style that captivated his audience.
AndyYes, booking is open. The advert is on the back of the December Journal and it was announced in the December email Newsletter.
AndyI have uploaded the meeting videos to the BAA YouTube channel. I provide links below for easy access. I divided the meeting into the 3 sessions, and in the YouTube video descriptions there are links so you can jump to each of the talks.
Unfortunately there were a few IT issues on the day so the recordings are not perfect. The first few minutes of the introduction were missed due to a recording issue, and then one of the microphones failed for the start of Paul Leyland’s talk. I have left all of Paul’s talk as you can still see the slides before I swapped his microphone.Session 1 (morning) – https://youtu.be/XIIO4Wbi6Rw
Session 2 (after lunch) – https://youtu.be/GmV6uenWiUM
Session 3 (after tea) – https://youtu.be/REQ3deLjfc8Here is the revised schedule for the day.
10:30 – Welcome and introduction. Director
10:50 – Richard Sargent – Hind’s Variable Nebula
11:20 – Paul Leyland – Observing extragalactic variables
11:50 – Jeremy Shears – Cluster variables in M5
12:20 – Chris Lloyd – Targets for Smart Scopes
12:50 – Lunch
14:15 – Brian Kloppenborg (Remote) – How AAVSO is adapting to the sky survey era
14:45 – David Boyd – Spectroscopy of the massive eclipsing binary VV Cephei
15:15 – Des Loughney – Using the MAST Database to study eclipsing binaries
15:45 – Tea
16:15 – John Toone – 50 years of visual photometry
16.45 – Ingrid Pelisoli (University of Warwick) – Discovering and characterising white dwarf pulsars
17:35 – Closing remarks – DirectorBest wishes,
AndyI am also staying at the Premier Inn. Friday night as well as Saturday night, as that is the only way I can be there for the start of the meeting.
Cheers,
Andy
