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Thanks to all for their hard work.
I imagine someone else has said it, but I would prefer the Forum and Tutorial sections swapped places on the front page.
The Forum I look at everyday, the Tutorials once in a blue moon.
Is Tutorials at the top to help attract new members?
A hugely skilled astronomer, a discoverer of supernovae, a telescope maker and an innovator.
A nice man who was generous with his time, fun to be with and happy to help others out.
More importantly than all that, Pat’s husband.
I’m glad I was lucky enough to know him.
Silly and unimportant comments….
Is it possible to force carriage returns in the Observer Profile? Do I need to put in the appropriate html?
Also, on the discussions, is it possible to have a link to the last post or most recent unread post or is that not possible within the new framework?
Like the dark mode….
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.
