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Council meets six times a year, normally at Burlington House. Usually these are on the same day as an ordinary meeting (morning or afternoon preceding the OM).
There are something like 35 people on council. Usually council meetings are quite well attended, with something like 20 – 25. A few council members (principally section directors) who live far away rarely attend.
It’s always good to get ‘new blood’ onto council, so please do stand if you are interested. All that’s expected is an enthusiam to contribute to the work of the association.
Cheers, Callum
If you use refracting optics IR will focus at a different point to the visible – so will lead to blurry images.
With a reflector this does not happen. But the IR will still be detected (silicon detectors tend to be more sensitive to IR than visible light), and cause the colour balance to be off (usually appearing much redder).
But that is something you could correct in photoshop (or whatever…)Callum
Hi Nick,
I am not an expert on the technique, though I have some understanding of how it should work… What sort of telescope were you using to do the observation?
Thanks, Callum
Although I used to use a laser pointer at star parties, I have become rather reticent in recent years. They do look rather ‘cool’ at night, so i’m not sure i’d like to encourage those who don’t understand the dangers…
There are already restrictions on use near airfields, and sensible use at star parties will probably not be a problem – but you might end with a visit from the police regardless these days… I am not sure the hassle would be worth it.
Callum
The Who’s who page has been updated with elected trustees and members of counci:
https://britastro.org/about-who
Cheers, Callum
Possibly the difficulty of fitting Spectroscopy into an existing observing section lends some strength to it being a section or group in it’s own right.
There are similarities with the Radio Astronomy Group, so something like that might suit.
Of course the recent changes to the BAA ‘constitution’ means that section directors are no longer trustees/directors of the ‘company’ – so there may be less reluctance to consider new sections – or perhaps a more flexible approach with special interest groups could be adopted.
Hope to make the spectroscopy meeting, but there is a Scotland match that day…
Callum
Yes, I always use and record the numbers from the SQM when i’m observing. I have a Unihedron one too. There is also an iPhone app but I don’t know how accurate it is. The app developers said they had difficulty doing an Android version because of the number of varieties of camera in the phones…
Callum
Hi Oliver,
I’m not an expert on polar aligning (being mainly a visual alt-az user), but my understanding for drift alignment is that you should choose an alignment star near the celestial equator and your meridian, so this maximises the effect of the drift, which will be minimal if you choose Polaris(?).
Clear skies. Callum
Another option is USB over Ethernet – i’ve not tried it but have been told it works well.. YMMV.
Callum
Hi Dominic,
For the widefield Lovejoy and winter dso’s that Ian took from Spain at the beginning of the year, these were with 50mm to 200mm lenses, and Canon 6D camera, and using an Astrotrac mount – according to Ian’s notes.
Callum
Hi Roger,
i’ve not come across anyone using this for wide-field imaging, if that is what you are thinking of.
The ‘trackers’ like the iOptron Sky Tracker and the Vixen Polarie are both popular, and the Astrotrak gives good results.
What are you wanting to do with the setup, and why looking for Goto?
Callum
I caught up with Cameron on Friday evening when I gave a talk at Coventry & Warwickshire AS – he’d recently taken delivery of his new scope – but plumped for something different, a second hand GSO 8″ F4 imaging newtonian.
Will be interesting to see what results he gets with that.
Callum
We had good conditions in Cheltenham until about 10:00 UT – when it clouded out. Though seems to have been locally a bit variable – my wife decided to stay home where it was cloudy and then cleared towards the end… I was so busy at the viewing event, though, I did not get much chance to take many photos…
I’ve posted some pics and chat at: http://starlightnights.com/callump/2015/03/the-uks-partial-solar-eclipse/
Callum
I was wondering if Denis’ meteor camera caught it – though maybe he points in a different direction…
Callum
Most of my experiments with a DSLR were with camera lenses on an old Canon 300d – so widefield mainly using fixed focus lenses – 8mm, 50mm and 85mm.
I found images were always better with dark frame subtraction.
I was never really sure how to do flat fields for ‘wide-field’ lenses – so never did.
I did use processing techniques for ‘synthetic’ flats, though, using IRIS.I have a new camera, Canon 600d, now, but not done much with it so far.
I expect it has much lower noise that the 300d, but whether it is neglible in exposures from 5s to 10s I have yet to measure.Callum.
Hi Jeremy,
if you select the text and use the link tool on the editor bar above (first line) you should be able to fix up the link. e.g.
http://www.britastro.org/vss/CSS%202126%20campaign_20140511%20(1).pdf
Cheers, Callum
Thanks Mike – i guess for many of us of a certain age Pluto will always hold a fascination.
For those not keeping up to date with my blog here is an image of Pluto on 30 July and 1st August.
I’m not sure the orientation is right – as Martin Mobberley points out iTelescope T18 has a “weird PA”. I think North is at about 1 o’clock…
Hi Cameron,
that’s a really nice image. I do like dso’s in their stary context like this, and you have nicely managed to capture the ‘wings’ which are often missed. Nice structure too.
Well done.
Looking forward to seeing more.
Clear skies, Callum
