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The easiest type of recording of talks to make is an HDMI interception of the projector display, coupled with a recording of the speaker. We have a ‘black box’ that does this, and I am thinking of using it at the forthcoming Cardiff meeting. This does not give a video showing the speakers, but it shows their talks content. The trouble is…it’s still not so simple. The achilles heel is the sound. The integrated sound recorder in the box does not give good quality if the speaker is somewhat away from it, or wandering around. The solution to this is to use a digital sound recorder with a lapel mic. We have this equipment as well. This, however, will not capture the speaking of the meeting chair, nor of questioners. And it gives someone a big job later to marry up the video with the sound. Since none of these small gadgets have a very clear display of what they are doing, it is easy to make mistakes and fail to record one or the other of the video or sound. It is not a job the chair of the meeting (i.e. me) should be doing, as the chair has multiple other things to think about. It needs a volunteer dedicated to the task. For last year’s meeting in Elgin, a member of the local society (or possibly they were university staff) succeeded in making such a recording of most of the talks, using university equipment, for which we are very grateful. Generally, however, it does not happen. I feel the only way we could ensure videos made of each meeting outside London would be to pay contractors. When you look at the numbers of people who watch our videos, they are, by YouTube global standards, very, very low. Therefore it is a decision we have to weigh up as to whether it is worth it. The arrangement we have with the Institute of Physics in London is fantastic, because their technician, at no cost to us, records the sound, the view in the hall, the faces of the speakers, and the slides. We still have to pay our staff to edit and upload the video, but in this case it seems justifiable.
If you wish to loose some weight after drinking that beer there’s a Moberley Sports Centre (one b) in Kensal Rise, NW London. I’m not sure if it should be pronounced Mobberley or Mowberley.
On Alex and Paul’s point, I think it is quite understandable that so many people get the terms astrology/astrologer and astronomy/astronomer confused. Other scientific disciplines have the ‘ology’ suffix – think of geology, meteorology, physiology, biology etc. ‘Astronomy’ is a peculiarity, linguistically. It means, literally, the naming of the stars. It would be more logical for the science of the stars to be called astrology.
I’ve been looking into this event, and, for the record, there seems to be an error in Bill Barton’s original post.
On 24 March the figures that were being given by news outlets for this close approach were that the asteroid would pass the Moon at 515,000km and Earth at 168,000km (not 68,000km). In fact this prediction was quite accurate, the miss distance being 175,000km. The object was measured at 70m diameter.
The BBC news article Bill linked to was revised on 25 March, but see, for example, the Guardian article:
https://www.theguardian.com/science/2023/mar/24/city-killer-asteroid-to-pass-harmlessly-between-earth-and-moonI wonder if what we need, in view of recent discoveries by the JWST of massive galaxies only 500 million years after the Big Bang, is a revival of the Steady State theory of cosmology, or some version of it. The detection of evolved galaxies further and further back in time through advancing telescope technology (that actually was going on for some time before JWST) does not fit with the standard model, and was not predicted.
The main discovery that caused the Steady State Theory to loose out against the Big Bang Theory in the 1960s was the discovery of the cosmic microwave background. But could there be some other explanation for that than the Big Bang, I wonder?
Allow me to formally welcome to the Association again 😀
I see this question exactly was asked on Cloudy nights forum in 2009. No-one seemed to have a good answer.
https://www.cloudynights.com/topic/231104-field-flattener-for-megrez-110/I’ve tried flatteners on telescopes they were not designed for, and they always improve the results over a non-flatted setup, though not necessarily as much as should be possible when using exactly the right thing for the job.
It might be best to find one or other of the lenses suggested in that thread second-hand and just try it out. It might not be fantastic but might be good enough to be getting on with without large expenditure.
Others may have other suggestions.
I think it would mainly cost an enormous amount of time to convert it into a telescope, but if the glass is suitable (and I really don’t know whether it is), it should be possible; after all, Andrew Common in the 19th century managed to build an even bigger telescope on an amateur basis, with little prior experience of mirror-making. The mechanics would perhaps be more challenging than the optics.
As for a remote BAA telescope, I have to say, without saying too much, that Council has not been very keen on going down that route, feeling it is a service well-covered by commercial suppliers, and not wanting to risk a ‘stranded asset’ that could be difficult to manage. But we may discuss it again.
The widow of John Wall has also offered me a 36″ mirror blank! I know nothing more about it (thickness, type of glass). Any interest in the BAA?
I mentioned and illustrated the occultation of Mars on the night of its opposition, December 8, in my Sky Notes at the end of the AGM (which is now on YouTube). This is between 5:00 and 6:00 exactly from London.
I was aware of the occultation of Uranus, but did not mention it as it is not visible from the UK.
I look forward to an in-depth account of the work at the observatory James. It sounds like the capstan needs high friction in the hoizontal direction but low in the vertical, so maybe it should be grooved.
Thanks for your comments Daryl. I’d say if you spend much time looking at the Moon and planets, or double stars, an ED refractor is a very worthwhile upgrade from a standard doublet. The resolution and colour perception are both substantially enhanced by the almost total lack of chromatic fringing. The other advantage is an ED can be made shorter for its aperture and still give good images. The standard 100ED refractor is f/9, but its performance is better probably than a normal 100mm doublet at f/13.
She has been a BAA member, but is lapsed. Still, it’s potentially good that she is interested in the subject.
Seems it’s only possible to post one image per thread in this forum system. Even when I tried to post again with another image it din’t allow it. I’ll have to ask the webmasters about that.
Here’s pictures of the military sighting gadgets I have here. The shorter one is a black-painted brass tube with both a helical focus and a moveable rack-and-pinion adjusted objective, for some reason. Gives an inverted image. No maker name. The other is by REL, Canada, dated 1942. It is a unity power telescope with an extendable objective shield and reticle, gives an erect image, and is a bit lighter than the other one. It looks exactly like a brass bicycle pump.
These gadgets always tend to be too heavy for their optical power to be of any use for astronomy.
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I wonder if there is any link here with A A Common, famous astronomer of Ealing and early member of the BAA. He was involved with the Ottway company and patented devices for sighting naval guns around 1900. Here is a partial listing of patents in his name; they are mostly around this subject. Note the patent numbers are nothing like that quoted, and are much longer. This doesn’t look like a correct patent number.
In the obituary of Common by F W Dyson in MNRAS (1903) it is stated that according to a Captain Percy Scott, RN, ‘The great strides made by the British Navy [in gunnery] lately was entirely due to Dr Common…. He had produced a telescopic gun sight that would, when properly used, quadruple the fighting efficiency of our battle-ships.’
I also have a similar gun sight in my collection. Ottways must have made a great many of them. I got mine from the workshop of telescope maker Irvings (Teddington) when they closed down.
David
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I have a lot of Handbook and Journal back-issues now from the collection of the late Bob Garner of Greenford, Middlesex.
I have plugged the gaps in my collection, so if anyone needs any, do let me know which you are seeking, before I dispose of the rest of them.
David
Yes, what Andy has said is correct.
The programming that is stalled because the programmers are in Ukraine is the overall programming for the system as used by all users, commercial and non-commercial. The idea was that when the basics of the system were working, a few of us would test it, then develop some instructions and make a web tutorial for members. The allocation of time to BAA members was (in part) a transaction in return for our advertising the company, and crediting it in any papers that used results from the telescope. The level of interest would determine whether we needed to devise a system of prioritising certain users. We might have just decided to pay for more time so as to avoid needing to prioritise anyone. If it proved really popular, buying footprint at the facility for a BAA-only telescope on the same system would have been considered as a later stage.
I hope to be able to impart some more news soon.
David
