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Ah, yes. I remember ansvr. Its a cygwin thing isn’t it? Surprised the guy who did the conversion job has not updated it Apparently, the absence of a true Windows version is due to the way AN maps the Index files to memory.
I was forced over to WSL (or Linux on a Rpi) because the ansvr version of AN is quite old and it was failing to solve some sparsely populated fields, while the latest AN did.
Ansvr certainly worked okay most the time though.
Thanks Grant.
Perhaps I should run the latest server on a Linux box which shares the control room with the Windoze TCS. It may well be faster and more effective than ANSVR (apologies for my typo earlier) but I’ve not yet done it on the grounds that if it aint broke, don’t fix it.
Both systems use the Gaia index files so images almost always solve because there is a large number of stars in those files. The Linux local astrometry.net installations (another one lives on my laptop) are not yet configured as servers so I will need to find out how to do that.
A local astrometry.net will also run under Windoze. It is what I use on my TCS. The search term “ANSRV” will find it for you if you are interested.
Thanks to everyone for great suggestions
Seconded.
I have a rather, err, crappy Meade here which was shipped almost 5 years ago and never put into use. When the next delivery of round tuits arrive I will put it into a roll-off shed under software control
Until then, I have now decided to buy a BBQ or motorbike cover pro tem.
This may or may not be applicable for you but I use a standard small car cover (a cover for small cars, rather than a small cover for cars though there is little difference between the two concepts in practice). A motorcycle cover may be more suitable for a smaller scope.
My cover is too big but I don’t care. Rope and/or bungee cords take good care of any excess.
I’d love to attend but I have to stay in La Palma until at least mid-September.
Will the meeting be recorded for later viewing? Recording is generally much easier than live streaming over Zoom or whatever.
Grant: good luck.
My view is that storage for all that baggage is cheap and the runtime fits easily within the 1G RAM on my Pi. I have little incentive to re-invent wheels, in other words.
What sort of control do you need over and above what EKOS/INDI can’t provide?
It works fine for me on a RPi 3B
David: The Vera Rubin telescope has both an enormous aperture (8.4m) and a very low focal ratio ( f/1.23). Its field of view exceeds my 0.4m f/6.5 scope about 20-fold and its collecting area about 200-fold (call it a limiting magnitude about 5 magnitudes fainter than mine).
But this is an exceptional case and your post applies to almost all telescopes and certainly all amateur telescopes.
Once more: the question comes back to: what is your budget?
Until we get sensible answers to this question, and to the one about intended use, the original question is indeed unanswerable.
Karl: what is your budget and what do you want to image?
Robin: I agree with you almost but not quite completely.
Part of my problem is that I do not have a good definition of the term “astrophotography” other than it appears to place pretty pictures much higher than their scientific value.
Is planetary imaging “astrophotography”? I don’t know. Neither do I know whether alt-az mounted DSLRs are used for “astrophotography” but they can certainly take pretty pictures, as well as take images which when analysed yield good science.
in positions 2 and 7 here you have a Dobsonian mounted scopes which are not suitable for astrophotography
While planetary imaging has different needs.
Indeed.
Martin Lewis takes some absolutely superb planetary images with his Dobsonian mounted telescopes. The rings of Uranus and surface detail on each of Ganymede, Mercury, and Venus are among some of his achievements.
Do you agree with what I have written? Any additional points I have missed?
When you describe reflectors you state that one mirror is flat. This true, by and large, only for Newtonians and other folded optical path designs. My scope is a sort of Cassegrain but, to be fair, it does contain a flat just before the camera or eyepiece assembly.
I find it amusing that you have a Celestron NexStar 5 SLT which is a Schmidt-Cassegrain I believe. It also has a flat for ease of uses near the zenith.
It does OK but I wonder if a much bigger scope (how big is best?)
How much do you want to spend?
A fully kitted out 4-metre telescope will produce some very fine images but is likely beyond your budget.
Your question as phrased is essentially unanswerable.
The above was for photometry. Add another 2 magnitudes or so for usable astrometry. I’ve uploaded images to the gallery where satellites in the outer solar system are visible at mag 22 or thereabouts.
Perhaps a start could be. What are others observing. What magnitude can useful work be carried out with say C8 or say 100mm APO.
KevinHow long is your piece of string, in other words.
I have done photometry of exoplanet transits, variable stars (eruptives / cataclysmics mostly) and asteroids but exceedingly little on LPVs and eclipsing variables. Extragalactic luminous blue variables have also had a lot of attention but I accept that I am seriously weird in some respects.
Reasonably good estimates for magnitude ranges can be obtained from any one data point scaled by collecting area. Here is my data point, based on a 0.4m aperture. It has four times the collecting area of a C8 and so the limiting magnitude is likely very close to 1.5 magnitudes fainter. A 100mm APO has 1/16 of the collecting area and so will be around 3 magnitudes inferior to a 400mm. Note that essentially all cameras have effectively the same detector sensitivity these days and so the make of the camera is largely irrelevant from a performance point of view.
I can manage 0.1 mag precision at V=20 with a ~3 hour exposure.
I regularly do 0.05-0.03 mag measurements down to V=18 or so.
For exoplanets, ~2mmag precision can be done down to perhaps mag 12-13 unfiltered at a reasonable cadence — 1-2 minutes perhaps.In the words of good old Usenet: HTH, YMMV, HAND.
Kevin:
I was a newbie at CCD photometry until quite recently and I agree the learning curve can be quite steep.
Have you found https://britastro.org/section_information_/variable-stars-section-overview/baavss-mentoring yet?
I may be able to help you but this forum is not the right place to do it in my opinion. If you would like to email me at paul (a) leyland.vispa.com we can see what can be done to get you started. We can’t easily meet in person because I’m in La Palma right now and after returning to Cambridge in a couple of months we will still be a fair distance apart. Phone and/or Skype/Zoom may be helpful as well as email.
Paul
According to Sidgwick, the resolution of a properly collimated 4″ refractor should be around 1.2-1.4 arcsec though, to be fair, those values are for resolving double stars rather than extended objects. That does, of course, assume that the ocular is illuminated by the whole objective. Back in Sidgwick’s day I suspect that 2″ eyepieces were extremely unlikely to be fitted to a 4″ refractor.
I have no idea what typical seeing is like at your location but guess that it is likely to be around 2-3 arcsec. That is a typical figure at Tacande Observatory though occasionally the seeing can be as good as 1-1.5 arcsec.
Neither do I have any idea about the acuity of your vision.
Based on this analysis, I suspect you are seeing limited. The phrase “most days” also leads me to this opinion.
