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Robin: true.
I question whether it is cheaper to put large structures in space or whether to put large structures (such as transmission lines) on the ground at a range of longitudes.
Or, for that matter, to install storage mechanisms to convert daylight solar energy into nighttime electricity. Batteries, in the general sense of the word, are relatively cheap. Raising a cubic kilometer of mass a hundred metres stores a lot of energy and uses technology which has been well understood and implemented for a hundred years. Melting and re-solidifying a phase-change material, such as NaCl, likewise.
Not obviously cost effective. It’s much cheaper to double the collecting area on the ground than to do so in space.
I’ve seen some where the entire image dynamic range is in the range of 0.0 to 1.0 and that clearly doesn’t work very well if you just truncate.
That is relatively sane compared with some formats I have seen. SWarp, in particular, can generate values which are negative and in a range which bears little resemblance to that of 16-bit signed integers. The result is fully compliant with the FITS standard and, for example, ds9 has no trouble dealing with such images.
That’s why I had to write my own conversion routine.
Ah, the beauty of standards!
It is very important, IMAO, to have a standard. So important that everyone should have one of their own.
Are the files roughly the same size? The raw files you get from the camera are probably 16-bit integer (BITPIX=16). After calibration they may be floating point (BITPIX=-32) and it may be that Vphot can’t cope with that. The FP files will be twice the size of the integer ones. If Vphot can’t cope with FP that is a bit poor but there may be an option in ASTAP to save as ints.
I hit exactly that problem with Astrometrica. To solve it I wrote a Perl script to convert from floating point back to 16-bit unsigned integers. Not entirely trivial because a FP number can be negative and the range can be greater than supported in 16 bits, so off-setting and scaling was required.
David: I am supposed to know what “oscillator strength” means in the context of time dependent quantum mechanics but my memory has rotted in the last 40 years or so and can no longer describe it particularly coherently. Time I ran a refresh cycle on my RAM.
Mark me as recently mystified.
Beside which, I will not be Astrofesting this year.
The FITS standard defines a format for metadata headers and mandates some of them.
Within reason, you can put pretty much anything in there. Whether a particular FITS-reading program interprets them in an intended manner is an entirely different matter.
For instance, whether either, neither, or both of “EXPOSURE” or “EXPTIME” is present depends on the writing program. My code to read FITS files has to be able to handle both and to work out what to do if their values differ.
Everyone else would need ear protection if I were to join in.
Only dogs like my singing; they howl along with me.
Grant, quick question: why do you want a monochrome camera on this kit?
I can answer why I might find one attractive: I like doing photometry in standard wavebands and also like capturing every possible photon for faint object detection and/or astrometry. I am not very interested in taking pretty picture.
Paul
I can take a look. I have SR, SI and TR filters available. SR has 90% transmission at H-alpha so perhaps that may be the best bet. I also have only 4% of the collecting area of the Hale but, there again, so does WISE.
No promises of seeing anything by myself, in other words, but perhaps any data I do take can be stacked with those of others.
Now that I am back in La Palma and have access to my observatory I can check the log book.
It appears that useful observations were made on 43 nights. More were undoubtedly clear, at least in part and some quite probably after I had given up waiting for the clouds to clear earlier in the night.
Bear in mind that I live in LP for less than half the year. In 2023 only 141 days were spent here and six of those were spent traveling.
As one might expect the evening I arrived here, 2024-01-11, was clear but I was exhausted after a trip which began at 02:00 that morning. The sky has been cloudy ever since.
David: please don’t recycle them. I would be happy to collect but I am off to La Palma in a couple of days, returning Easter-ish, so can’t do anything any time soon. If others want them, please give them priority.
BTW, I have a bunch of BAA Handbook back issues which are free to a good home. They are duplicates of my main collection which is essentially complete back to the 1940s. If anyone may be able to fill gaps, please let me know.
Paul
I also thought the same as Bill.
But soon realised it couldn’t be because of its angle and direction in the sky.
I may be naive, but I thought that sporadics could come from any direction at any time.
If that is the case, I don’t see why one shouldn’t masquerade as a shower meteor.
That said, I am very far from being an expert in these matters and welcome comments from those who are.
(Yes, I agree with the analysis that it was not a Quadrantid.)
Well, the Earth didn’t move for me, darling, unlike 2021 when some of the tremors went over Richter 3.0.
I don’t have precise figures to hand right now but impressions are that 2023 wasn’t so much different than the previous couple of years. Cloud was much better than in the UK but calima (hot air bringing dust directly from the Sahara) was as objectionable as ever. In the summer the calima heat was so bad that the camera’s Peltier cooler couldn’t maintain -10C and the mount controller would crash somewhere between 30 seconds and 30 minutes after starting. The latter was eventually kludged around with an old 4″, 12V fan held on with cable ties.
For TheSky error with PHD you need to run TheSky one-time-only “As Administrator” so that TheSky’s automation interface is registered with Windows.
…
Assuming the above steps fix the problem reboot the computer and carry out a manual “check for Windows updates” from the Windows Settings tool to ensure the Windows Update service is working properly.That was it! Discovered it myself a long time ago by trial and error, which is why it was both familiar and not immediately to mind.
My TCS has had Windows Update switched off in a hard-wired registry setting, so WU never works even when explicitly asked for. That way a working system doesn’t get munged by Microsoft into a non-working one. If it aint broke, don’t fix it. I am not concerned with security vulnerabilities as it is a dedicated system and heavily protected with multiple levels of firewalls. A simple web search will tell you how to follow suit should you wish.
Paul
