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Hello David. Great news to hear that the telescope is now on the move to the Beamish Open Air Museum. One thing that is puzzling me though is why is the Ash Dome not being used in the construction of the new observatory. Unless there are two Ash Domes. Mel
Beamish have said they would prefer to build a replica of Espin’s original Tow Law Observatory. The Ash Dome was a later addition to the Close House observatory by the University and was the home of a rather good 14″ Meade SCT.
If the locals get their act together in time, please ensure that the dome goes to them.
Otherwise I will pay a (fairly) nominal sum for the dome and arrange for transport to La Palma. Assuming your dome is in reasonably good condition. shipping will be noticeably cheaper than buying a new dome for the 0.4m R-C which is currently lying on a floor at Tacande Observatory. An EQ-8 mount is already ready for it.
From experience, I know that Ash domes are of very good quality but, being made of galvanized steel, require regular maintenance to stop rust. Another round of treatment is required on my Ash dome when I return to Tacande next year.
Feel free to continue further correspondence to email — or continue here if you wish.
Paul
After several years of observing, I’ve accumulated a huge amount of astronomical data in FITS format. I’m curious how others organize and index their collections. Are there any good software tools that handle this well and keep large datasets properly organized and searchable?
I use a PostgreSQL database to hold all the metadata for my collection of images, almost all of which is in the form of FITS-format images. My collection now has just short of 45K images in the database, with a similar amount yet to be processed. I do not know whether that is huge by your standards but PostgreSQL can certainly manage several orders of magnitude more than that. PostgreSQL is OS-agnostic and is used by many professional sites to handle databases — up to at least a terabyte..
Being a command-line geek, I tend to search it through direct SQL commands. A number of pointy-click GUI applications are readily available, again OS-agnostic.
Very willing to provide the schema and associated software to anyone who would like it. If it is of general interest we can continue the discussion here. If not, please contact me by PM or email.
Works well for me. YMMV.
Paul
How big is the dome? I have a 0.4m (~16″) Ritchey-Chretien which needs housing. My other 0.4m, a Dilworth, is already inside an Ash dome.
Unfortunately your dome is in the UK and my telescope is in La Palma. Depending on size, weight, and price it may be worth shipping.
Paul
Hi Connor,
Not necessarily binaries, but some variables which are good to start doing photometry on with the default S50 settings (i.e. 10s exposures) are:
T CrB
RY Leo
TX CVn
V UMa
U Boo
OO Aql
SW Cyg
BR CygThese all fall in a useful magnitued range to analyse each of the 10s exposures, and a good starting place I feel as no stacking should be necessary under reasonable conditions. If there is concern around the photometry mode in the S50 these are all easy enough export from the scope and analyse using other software.
Please beware that unless you calibrate your detector carefully and apply the transformation coefficients so produced, your magnitude measurements are unlikely to be close to those reported by other observers.
For time-resolved photometry, such as determining the time of minima of eclipsing variables, this doesn’t much matter. It is the times of the observations which is important, not the magnitude measurements on any particular scale per se.
Don’t let this discourage you from doing useful work. Especially don’t let it discourage you from learning how to calibrate your telescope and so go on to work on the full range of fields available. The BAA-VSS people are very willing to help you take this step.
Paul
I have been on the road for several days and have only just seen this.
My collection of AN is fairly extensive but not complete, especially not the early ones.
I am also building up a substantial library, as Richard already knows.
Paul
I’m not particularly qualified to comment on the science or technical aspect of the original post but I would say that for some the size of image files could be a factor. Personally, I don’t take a lot of RAW images as a lot of my photography is of meteors, noctilucent clouds and night sky time lapses. As such, memory space is very much a concern. For example, I’ve taken well over 30,000 images since July.
Ah, but you are not doing high accuracy photometry with your images.
External USB 8TB drives appear to be £250-300 these days. You don’t say how big your images are but 100MB each is a generous estimate as far as I can tell. That could get quite expensive if you need to buy three disks per annum, enough to hold 240K or so images.
My images are rather smaller, in the range 2-20M, and I don’t take anywhere the number you do. That said, the SeeStar can churn them out at a helluva rate but those are at least relatively small at just under 4M per FITS format sub. At the standard exposure time of 10s, an hour is 360*4 = 1.44G and a total exposure time of around 5600 hours (circa 230 days) can be stored on a 8TB disk. Given the weather we have and the fact that it is dark for less than 50% of the time, such a disk would last me well over a year and likely several.
Horses for courses.
Paul
I am not really competent to comment on the majority of your material above.
What I would advocate, however, is that you use RAW exclusively if you wish to produce high quality photometry which is compatible with that produced by others. JPEG, TIF, PNG, et al. can do very weird things to the data over and above what the camera itself may do in the area of noise reduction, white balancing and so on.
You likely know all this; I make it clear for the benefit of those readers who may not have come across this concern.
What is the source of your “to avoid taking up too much memory” concern? Not disk space, surely, as multi-terabyte hard disks are dirt cheap these days. Let’s be generous and say a single image uses 100MB. That means a single terabyte will hold ten thousand images. How many images do you take each year?
Paul
There seem to be a couple of residual problems following the steps taken to resolve the recent performance problem.
This problem also occurs on Safari, so probably not browser specific.
So was I right? Bots scraping the entire site?
Trying to suck out thousands of large files would undoubtedly put a strain on both the server and its bandwidth to the interweb thingy.
Any update on this one?
Other fora which show similar symptoms generally find that they are being hit by bots in their thousands trying to scrape their entire content, allegedly for AI training purposes. Trying to stop them often turns into a game of whack-a-mole, though black listing IP addresses which make more than a certain number of accesses in a specified period can be very effective. The latter requires that software is in place, which can be tricky if no-one has thought about its provision beforehand.
Good luck!
Paul
I think Robin and Paul are right. Engaging via online fora is one of the best ways to show people the science side of astronomy. All 3 of us spend quite a bit of time on SGL. Robin is often posting about spectroscopy and Paul if often pointing out to imagers the interesting objects that are in the images of well known objects they post, like globulars in M31.I sometimes post about variable stars. It’s a matter of gently encouraging others to do more.
Sounds like a call to arms to me.
OK, so what is everyone waiting for? 🙂
Grant: I really don’t know, not being privy to the detailed discussions. All I can report is what a couple of the supporting moderators passed on in private messages.
I don’t understand why the proposal was controversial either.
Paul
Robin: I had enormous trouble getting CN’s Scientific Amateur Astronomy section created. Some moderators (mentioning no names in order to protect the guilty) were very antagonistic but a few were equally enthusiastic. The enthusiasts won out in the end, after what one moderator described as a “💩-storm” in the moderator’s community. The descriptive text:
A forum where amateurs can discuss their contributions to fields such as spectroscopy, photometry, astrometry, interferometry, and radio astronomy. Astronomical objects of interest may include variable and carbon stars, pulsars, supernovae, AGNs, exoplanets, asteroids, and short-lived energetic phenomena such as GRBs. The presentation of quantitative observational measurements, techniques used for acquisition, and relevant ensuing discussion are especially welcome.
is entirely mine, apart from the later addition of “and carbon stars”.
Your work promoting spectroscopy there has paid dividends. Kudos!
Other areas, especially photometry but including astrometry and radio astronomy also have a productive community.
FWIW, I am also a member of SGL. Amongst my other efforts, I annotate the plentiful images of M31 and M33 to show the locations of globular clusters, LBVs and Cepheids; explain workflow in photometry, and post an annual image showing the proper motion of Barnard’s star. Each of these have had a positive response. A few “pretty pictures” afficionados have asked for, and received, catalogues of globular clusters in Local Group galaxies so that they can track down more examples in their images.
I also plug the BAA, especially the ARPS and its asteroidal photometry programme in both CN and SGL.
The lesson, I suggest, that other BAA members should follow Robin’s and my lead in creating mass-audience sub-fora and in encouraging their readers to contribute material of scientific value. Beware: it may prove to be hard work.
Paul
My site was at Albarracín. To the naked eye the corona looked golden, which I ascribed to the low altitude.
Through a 100mm spotting scope at 60x, the corona was a very pale yellow. An enormous prominence on the left (east) limb was a brilliant red. The line on the other limb didn’t extend as far out but was much longer; it was the same colour. As soon as the first Bailley’s beads appeared I stopped watching through the telescope.
We were incredibly lucky at that site. As the sun set it went behind a bank of clouds at about 40% phase. It reappeared a minute or so before totality and remained in clear sky until sunset. A few kilometres away in Teruel they had the opposite experience: clear for the majority of the partial phase and totality completely obscured.
I wish I had my “Unusual Telescopes” book with me. Towards the back there is a photo showing two people each making a pinhole camera and projection screen using only their hands.
Perhaps people reading this may like to give it a try.
The UoM has a donation facility to support Jodrell Bank, reachable from the link in Jeremy’s post.
There has been quite a bit of activity there, with 278 pages listing donations when I went there a few minutes ago.
