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On 25minutes worth of frames I am seeing something very dim and (on my frame) at the 7 o’clock position from the 15.7 mag star, but that seems slightly out of position compared to the AAVSO chart. Is that it?
Gary,
I’m on target now and not seeing it – unless its very, very close to the 15.7 star and the two appear merged.
Could it have faded already?
Grant
EDIT: Image attached. Pixel=1.54″ so field ~25arc min wide.
Attachments:
Hi Andy,
Yes, I can imagine everyone would think “Wow! Thats a great opportunity.”, but surely before engaging programmers there must have been some vague plan for how that time would be used?
Not meaning to be awkward, but I’m curious as to what the Council thinking was. 🙂 There is obviously quite a range of possibilities.
Grant
Hi Callum,
Oh yes, now you mention it I think I recall seeing that once before. So, that would be used in some way for scheduling one imagines, but scheduling what?
Is the BAA thinking of buying telescope time from a commercial site, buying footprint at a managed facility and setting up their own scope or buying a BAA defined system to be run at the site in question. What sort of operating model are they thinking of?
Similarly, is this intended purely as a recruitment carrot to dangle or would it (if a BAA system) also be available for the sections so its output every year did not consist of entirely of another 2000 narrowband images of M42, M31 and M45.
Grant
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.
