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Nick James
ParticipantRobin – I’m not aware of any recordings of that meeting.
Nick James
ParticipantThanks Jeremy. It was just like old times for me reading out the list of papers!
Nick James
ParticipantPeter – That’s a shame but, as others have said, we have constraints too and so it is not always possible to avoid a clash.
Nick James
ParticipantNice spectra of a very interesting object.
Nick James
ParticipantLars. Thanks. It’s great to know that these are appreciated.
Nick James
ParticipantThe other talks are now up on our website here.
Nick James
ParticipantDavid, Thanks for the heads up on this. I imaged it this morning using a widefield instrument so the trail is small but it is visible. The observation is here.
Nick James
ParticipantBrilliant work. These absolute spectra really show the evolution well.
Do you think physics will ever adopt SI units? It is one of the significant differences between physics and engineering and I have to keep looking up the scale factor between ergs and Joules. I suppose CGS is better than BTUs and feet…
Nick James
ParticipantSo it does. Denis is a very dedicated comet observer not so used to imaging bright point sources that don’t move…
Nick James
ParticipantMike. Very nice. That H-alpha emission is very strong.
Nick James
ParticipantAfter a nice day the evening was very hazy with a lot of cirrus but I did manage to get a picture of it in a small gap. The attached is a single 15s exposure at ISO800 with a 100mm f/2 lens at f/2.8. Capella is the bright star at lower left. The nova appears very red on this image.
Nick James
ParticipantGreat stuff. Now if only we could get a clear sky in the southeast of England…
Nick James
ParticipantGreat video. If you stack the frames using minimum pixel hold you should be able to get a nice still showing it moving across. I’ve only ever succesfully imaged this once on 2011 May 25 using a DSLR. Each video frame was minimum pixel stacked to get this effect.
Nick James
ParticipantA seminal paper. Kudos for referencing Kepler’s 1619 Harmonices Mundi.
Nick James
ParticipantIndeed. I’ve been doing this for years with a cheap Dell in the observatory. My PC death rate is around one death every 2-3 years but I keep a disk image so replacement is dead easy. Windows RDP is certainly secure enough to use on an internal network. I wouldn’t expose it directly to the internet though unless your network firewall can restrict access to particular IPs.
Nick James
ParticipantThe GPL Positional Astronomy Library (PAL) can be found on Github here. It is an open-source reworking of Patrick Wallace’s slalib and it contains all the functions you need to do this. Alternatively the original slalib in Fortran is GPL and should be available somewhere. Even if you can’t use these functions directly they are a good source of information on how to do the conversion accurately.
Nick James
ParticipantExcellent. Good job Prof. Dunsby has got a sense of humour!
Nick James
ParticipantYes, that’s the micrometer. Imagine taking a long exposure of a comet (30 mins to an hour) using offset guiding on a star. The micrometer was rotated to the appropriate PA and then used to get the correct offset rate. If you messed up you wouldn’t know until you developed the single film frame sometime later. Imaging was really hard work in those days! Have a look at this example and read the caption to see what I mean.
Nick James
ParticipantYes, Mike will be very sadly missed. He was director of the Comet Section at a key time which included the return of 1P/Halley. Mike edited the BAA Memoir on this comet which was a huge undertaking. We have the Newsletters from that time available online via the link in here and they are a good example of how different observing was in those far off days. The attached pics show Mike with the 25cm reflector he used for his Halley imaging and the 6-inch Cooke that he used for his prominence images that Richard has posted.
Nick James
ParticipantGrant,
My only experience of USB over Ethernet has been very bad, and that was using a pro system in work. Much easier to buy a cheap PC from ebay, stick it in the observatory, leave it running permanently, connect a Cat 6 LAN cable to it, then run all the USB connections locally. You can then either remote desktop to it or run ASCOM remote from inside. Much more reliable and it’ll set you back £50 or so.
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