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I remember my consternation when I first encountered a professional astronomer who had not been an amateur observer when a teenager. It seemed shocking.
However, with the advent of blind plate solving and smart scopes I think we are about to encounter an influx of amateurs in the same position.
In fairness, eyeballing an object through a 2m scope wouldn’t yield much beyond a subjective drawing and you would still miss the really faint stuff.
Hang on. I just thought. You talked about an ME 2 years ago.
From the forum it looked like the gears were not properly engaged and you might have had trouble with a serial to USB adapter. Is this the same scope?
You mention in that old forum that you were using Sky6. Why? I thought this was a new install and part of the purchase deal for a Paramount is a TSX licence. Why would you use the old code?
How far out is the mount N/S alignment? Iron piers can be a pain because of their impact on a compass. Also, have you set the approximate latitude on the mount properly ie within a degree or two?
So, you power up. You connect TSX successfully and you tell TSX to go home. Does it do that, making the bing bong noises it uses when it finds Home AND afterwards, are the lights on the mount the colours the manual says they should be (off hand, I don’t remember what they should be for an ME)?
So, if you Go Home and then tell TSX to do sidereal tracking and try to image a star through the scope do you get untrailed star like images?
Can I assume you have changed your location in TSX to the mount’s current location / height – Google or similar will easily give you 3 decimal place accuracy – height accuracy doesn’t have to be perfect. Also, how is your computer time being maintained? If a network is available Sync the time in Windows Settings or use the Meinberg server software. If not available then a £9 USB GPS dongle will do the job if used with NMEATIME2 software (cheap licence). Laptops have internal clocks but closing down Windows or not using the laptop for a week or two can -in some cases – lead to a big time difference between the laptop time and the real world.
Further question, do you have the T-Point add on? That would make life much simpler.
The major difference between a JPG and a TIFF is that a normal JPG will only ever have 8 bit data, while a TIFF can contain 8, 16, 48 or even 96 bit data, depending on how the RGB bands are handled. So, TIFF data can allow a higher resolution measurement than a JPG, which also means a greater dynamic range of values can be represented.
Another difference is that the JPG image created by the Nikon will have been heavily filtered by the Digic. I have no idea exactly what Nikon* do, but presumably artefact suppresion with a large side order of spatial filtering feature in the dark parts of the frame. The joy of using the TIFF data is that you get to control what you permit Matlab to do to your RAW data. Certainly the JPG/RAW profiles showed signs of the background in JPGs being very harhly denoised and that might hide subtle detail
You don’t say if you have applied dark subtraction to your RAW image. If not, that would probably suppress the noise in the RAW frame a little.
As to what JPGing does: if the image compression is overdone, it can create faint square box features in some parts of the image. However, Nikon** will almost certainly apply it well enough that the squares will not be obvious in the JPG without a hefty contrast stretch, but they can – potentially – impact your photometry slightly.
For me, if I wanted to derive meaningful numbers from a dataset, I would always use the dark subtracted RAW files – but JPGs may be useful for sorting out what you want to do to the data.
Hope some of this helps. 🙂
*Or for that matter what Canon do. Both companies are reticent on the subject.
**My camera is a Canon.That looks hopeful.
Will be interesting to see how the results contrast with those seen in the RGO competition entries where whacking the saturation up to 11 and overdoing the “enhancement” seems to be increasingly popular.
Just a thought: perhaps there might even be be monochrome entries! Gosh.
Hi Paul,
I’m curious, what was it that some of the moderators objected to in scientifc amateur astronomy? Seems fairly innocuous.
I’m struggling to see how it causes offence.
Grant
I got a very similar result at Lebrancon near Molinas de Aragon.
I assumed the cause was 3 fold:
Extinction due to the low solar elevatio at totality
Dust suspended in the atmosphere – Spain was bone dry (our car was covered with it)
Smoke particles arising from the wildfiresCertainly on a cloud free day in Madrid the day before, the sky was not blue but whitish – I would swear when we left the hotel we could faintly smell burning one day.
Attachments:
For context: subsidising the bars and restaurants at Parliament cost ~£6M a year.
Strangely enough, when I worked irregular and deeply unsocial hours at work no restaurants or bars were made available. Management suggested a packed lunch.
Yep. My guess is that Jodrell will be “saved” due to its high profile, while La Palma, the JCMT and VR etc are thrown to the dogs.
Its almost as if the people who end up in politics lack a basic understanding of the fact a modern technological society needs scientists.
Its not as if jobs in UK science offer security, high pay, respect and glamour.
For context, the Barclays Bank bonus pot for the current year is running at £1.3B. Barclays could halve this years bonuses and still pay for Jodrell for 230 years.
I just looked and they still do grinding materials.
https://www.scientificmirrors.co.uk/telescope%20making%20supplies.html
Just to add to the fun:
https://www.sec.gov/Archives/edgar/data/1181412/000162828026036936/spaceexplorationtechnologi.htm
“In 2025 alone, Starlink satellites proactively performed over 1,000 automated collision avoidance maneuvers per day“ on page 9.
Either they are happy to throw away propellant or this is not good.
Thanks for the headsup on AA9 SP4 releasing. I will go and get it.
I think if AA4 coukd do a GUI I would be using it instead of Python – when I eventually finish that.
That is entirely my mistake I fear – see other Artemis thread.
JPL Horizons currently gives:
Rises above 10 degs 00:17 UTC
Culminates (15.07) 00:52 UTC
Drops below 10 degs 03:42 UTCJPL says launch was at 22:35:12UTC
It further says “Launch + 1/01:08 – Star Translunar Injection Burn”
I read that as 1day + 1hour+8min or 23:43 UTC but somehow converted it to 00:43 BST – a dumb BST/UTC mess up on my part.
Apologies to all.
We will miss the burn, but it will reach 15 degrees from the south coast!
Lets hope it stays clear.
I also find TSX’s limitatios frustrating.
For objects like that I just type* the RA/Dec into TSX, tell it to use J2000 and then tell it to slew to the coordinates.
*Pasting works too.
Hi Wayne,
That all looks fun and pretty short too considering everything it does.
AstroArt really is something. Coincidentally, I think the latest “Comets Tale” has an account of how Nick Quinn addressed the same problem with AstroArt and Arduinos/Rpis thrown in.
Is the full AstroArt command set documented anywhere?
I wondered about using AA for my current system – the first language I used was a Basic – but eventually went with trying to do something under Alpaca/ASCOM’s Alpyca. So I’m controlling my ASCOM devices in Python which allows me to use libraries like Astropy and I do my platesolving via a WSL Ubuntu instance of Astrometry.net – which I have to say was a bit fiddly to get going on Windows 11. I will probably need to program my own focus routine and PHD2 interface as well, so your route may well make more sense (though the focuser bit is easy enough). 🙂
One query, what is “Focuser.SoftwareCompensation(1)”? Is that setting the focus for he current ambient temp?
Grant
Evening Nick,
I vaguely recall thats been around a while. I considered it when I used a Canon 1100D but was worried it might brick it.
But, as it happens, I now use an M5 and apparently its not yet compatible.
So its currently looking like a Linux laptop needs building and I need to start some testing. 🙂
Thats very interesting. Had never heard of it. Thank you!
Looks a fairly simple syntax doing exactly what I need.
Shame it doesn’t run under Windows but I have WSL or I could just build a Linux Mint laptop and install python, Thunderbird, LibreOffice and Firefox. Thats all I would need to do what I do most the time and keep contact with home.
Am unclear from the github site. Is this running via a normal USB cable – like accessing the DCIM folder to download images?
1min45sec doesn’t allow time to faff with exposure – hence my concern!
Yes, I have one of them. But I rather fancied going from 1/1000th sec up to 1/10th sec rather than all the pics at the same exposure. But take your point. Simplicity is nice.
EDIT: Hell. I didn’t spot it does exposure too! That looks more interesting certainly. I will see if it does sequences. Thanks for the heads up. Assumed it just triggered the camera with the current exposure setting.
And just to make sure we get a Kessler cascade….
China don’t want to be left out.
