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That sounds hopeful. I shall have to read round that a bit. Presumably, the files are each for a declination swathe then?
I had forgotten there was an astometry.net group. Thanks for the reminder.
EDIT: I was wrong. Its not as simple as I had envisaged. These links appear to show the declination versus index file relationship…
https://github.com/dstndstn/astrometry.net/blob/main/util/hp.png
https://github.com/dstndstn/astrometry.net/blob/main/util/hp2.png
Realistically, looking at the layout, a better speed increase could be achieved by running multiple instances of astometry.net simultaneously, so I shall take that route instead. Theres no point having multi-core/threaded machines if you don’t redline them occasionally. 🙂
I was finding astrometry.net could take up to 30s on a frame if it had no idea of your field size nor where it was pointing.
However, for a 2700×2200 sensor its taking about 8 seconds per frame (using a Celeron 2 core 2.1GHz) if it knows the approx field location and size. But I was supplying it with coordinates for up to 2000 stars – looking for anything vaguely star shaped with an SNR>10. With a Lodestar that dropped to 2.5s.
A lot of pieces of software don’t seem to consider a slowly moving target.
Silly question, would it be possible to edit the index files so that (say) all declinations further south than -20 were not included. That would improve the search time for blind searches. Has anyone done that?
Astrometry.net is a blind solver, but it runs much faster if you give it a guess at the field centre RA/Dec or have an idea how big your field of view is.
I used to use ansvr, but I realised that the version of astometry.net implemented is quite out of date compared to the Linux version and was sometimes failing to find a solution when a friend’s more recent Linux version succeeded. However, when I had a problem the ansvr author was quite helpful – as were the guys who wrote astrometry.net.
Could you test ansvr from a command line?
If you are able to use Python – or similar – its worth installing the W10 WSL2 option and running a Linux astometry.net session from W10. Its how I now work – the start up time for WSL2 sessions is quite small (will be even better in W11).
Yep. Thats what I do
Sychronising is awkward as I need to jog the scope using TheSkyX and last time it was a long way out. Perhaps after my right angled finder arrives….
Will see what happens tonight. Looks clear!
Apparently, the American Optical Corp, made several analogous systems in the 60s for reconnaissance systems. Though theirs was 3″ aperture, 7″ long and ran at f/35.
A friend, keen on cameras, pointed me at this… https://www.photo.net/discuss/threads/vivitar-series-1-600mm-f8-solid-catadioptric-telephoto-lens.5501861/ and said the bokeh put people off them.
Yep. Courtesy of the great Pat Wallace. I see that the original Fortran code was being used for setting up a major professional observatory as recently as 2 years ago. I saw a presentation by him on the code once. Impressive piece of work.
Will try doing 25 stars and then add more every night instead. Will also see how far I can reduce the exposure and repeats and still work. Would be good to get it down to 15mins. Though, better yet, for it not to forget the model..
Will give that a go! Probably in a couple of nights time…
Even done automatically a 36 point T-Point takes 30-45mins out of the night – especially with the moon around driving up the sky backgrounds.
Thanks.
No, I don’t. I assumed that, if it was delivering the star to near the field centre then the TPoint model was working fine and I didn’t need to do anything.
Is that an error on my part?
Would be nice if it was as trivial as that.
No clear night here in 2 weeks.
I think the blog now says the starboard boom is out and the tensioning of the sunshield will begin.
Your JWST mag report is very hopeful for getting images at L2.
What mag was the rocket body? Can I assume that won’t reach even a semi-stable orbit and will quickly drift away? Might be an interesting observation target for a while.
Same in Wiltshire. Impressed by the Highlands having 4 clear nights in the last week when we cannot manage 1.
Nicely placed for observation from the UK then. I’m looking forward to imaging this.
How far apart will it be from the vehicle that launched it?
Lodestars are pretty good – 1st gen is probably good enough, as is the ZWO ASI120mm. I’m considering those for my camera to do a similar thing. Saw a second hand Lodestar today for £150 and the ASI is similarly priced. A significant part of the cost would be the lens on top… I will probably control mine via a Raspberry Pi.
I’m sure other have better ideas though.
Oh, SOLO. That has saved some cursing on my part….
Thank you!
EDIT: the 56MPH winds forecast for here at the time kind of dampen enthusiasm….
Apologies if my flippant cynicism inadvertently caused offence. It had not occurred to me I was making a political statement. I felt I was merely commenting on an aspect of modern day life familiar to many. Good products being tweaked to increase the profit margin and becoming less attractive to many. I would cite the frivolous example of a Mars Bar. The “New Improved” iterations have made them smaller, always less substantial and always containing less chocolate solids. Same name, different product.
The S&T magazine was originally really very good indeed – many serious UK astronomers read it and I avidly consumed it when I returned to amateur astronomy in the early 90s. I am proud to have had an article published in it. It was a great read. Something to look forward to. Then, someone else bought it.
The reviews became less in depth, material of interest to non-beginners became less common, several good writers left and it became much, much, thinner. I certainly gave up my subscription as it diminished. From my viewpoint it became not worth the money when it stopped serving the whole community.
I am delighted to hear S&T is thriving again and that de Cicco et al are still doing good work. If I ever come across a copy I shall give it a go.
But, for future reference: what would be an acceptable non-political phrase to refer to the people who, from my viewpoint, ruined a quality product?
The 4″ Unistellar you are currently using is quite capable of making useful observations. I am currently using a 4″ Skywatcher Newt to look at variable stars and started submitting results – after a 30 year gap. Working out the magnitudes of the stars is something fun to do on the numerous cloudy nights.
The instrumentation bar to participation in useful observing is very low. A pair of binoculars and a notebook can be a good starting point.
I would just note that the second paragraph of the website’s About Us webpage makes a big thing about the society encouraging useful observation:
“Since the beginning the BAA has encouraged amateurs to make scientifically valuable observations, often in collaboration with professional colleagues.”
I am a deep sky observer and so far from against taking the occasional “pretty pictures” as my personal Album testifies – IC342 for example. But, apart from as training exercises, what would astronomy gain from hundreds more images of the Messier Top Ten? What makes the BAA stand out from the vast majority of local societies is the degree to which it does encourage useful observation.
On the subject of instruments I suggested a RASA and a C11 as a wide field and narrow field/filtered co-mounted straw man option, but 2x C11 could also work nicely if a spectroscopic option was supported (and would not strain a Paramount or 10 Micron) – I just figured planetary observing would probably be more widely supported than spectral.
Will be interested to see what, if anything, transpires.
Grant (a humble ordinary member) 🙂
I think its more to do with the angle the solar panels are being maintained at.
I was impressed enough with them making naked-eye visibility. 🙂
Flares happen petty much every night (if the satellite isn’t eclipsed by the Earth). I have certainly recorded some as mag 5.
Worth noting that, depending on their stance, they may not flare when they are nearest the antisolar point, but up to 45 minutes earlier or later. I recorded one flare 3 hours later than antisolar – but that satellite was thrusting at the time.
Alternatively, how about setting up a scope at a hosted site and giving each section nights in turn so the VSS can go through dozens of VS a night, the comet section can do all comets visible from site and greater than mag 18, the Asteroid section could chase low phase angles and some compromise reached to allow good amounts of planetary observing at the most favourable point of the nights. You could cover a lot with a Paramount and co-mounted C11 and 11″ RASAs.
A simple criteria: data collected must lead to papers or it doesn’t get collected.
