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I don’t see why not – but am happy to be corrected if I am wrong.
I use a coma corrector on my telescope and do photometry.
Just be sure to always do dark subtraction and flat fielding.
I wanted to write my own code for controlling the camera without carrying along the huge baggage of filter wheels, dome control, mounts, derotators etc that will never be used.
As I have written code previously for the cameras to run under VB6 I hoped it wouldn’t be stupidly difficult.
With the RPi, I have found the problem to be that I do not have drivers for the SX cameras. I made it so the RPi recognises my Lodestar camera when it is plugged in, but it doesn’t have a driver to associate.
Previously, I went looking for the EKOS source on github and when I searched for the phrases “Starlight” or “sx” I found nothing. Having, accidentally, missed the introduction of github I must admit to some confusion/uncertainty as to how it works but didn’t seem able to find anything about the SX cameras. Must get a “Github for Dummies” book sometime.
Prompted by you I have now again looked at the Indi site and this time spotted that the cpp driver code appears to be available at http://svn.code.sf.net/p/indi/code/trunk/3rdparty/indi-sx/
I will download it all shortly.I shall have a play. Not quite sure how it will go, as its 20 years since I did C++ in anger, so it should be an interesting learning experience. There may be bad language at some point. Hopefully, I can eventually tie it all into Python / QT.
If anyone has already gone this route. Any “lessons learned” would be welcome.
I measured it at mag 15.0 and a couple of arc minutes out of position. Think it was doing 47 arc secs / minute. Had not realised it would be so bright.
It will get harder once they stop the orbits and head for the Moon.
I processed last nights data and got magnitudes of between 13.8-14.0 (Gaia g unfiltered) with a 0.12 mag spread – which is okay given it was initially viewed through a hedge and very low. Position errors were within the seeing disk.
Give it was moving at ~300 arc secs/min I used either 1s or 0.6s exposures. I think that was near perigee. It looks rather slower tonight.
Its clear tonight so, after 90mins on Gyulbudaghian’s, I had a bash with the 300mm Newtonian. Hadn’t noticed how fast Chandrayaan-3 was predicted to be moving. 4 arc secs per second…
Got it in 1 sec exposures. Will work out a magnitude tomorrow.First observations were through a hedge which really did not help.
Ah, had not realised that.
So it could have more pages or it could change its content or both could happen!
I know what I would prefer but this isn’t the place for that discussion.
Thats an interesting read and pretty much correlates with what I heard from an academic earlier this year.
Looks like current darks are important and for aesthetic purposes a median smooth may help some of the noise that doesn’t respond to sigma clipping – on account of not being from a Normal distribution.
It does make the QHY600 a very attractive prospect.
Nice to see CMOS has finally (nearly) caught up with CCDs. I first remember hearing of them from a friend in the mid 90s – the noise characteristics then were hideous.
Of course a 123MB image is a little worrying. I might need a 2TB drive a bit sharpish, if I bought one of those.
Thanks for the reply.
Yes, I did look at the SX Mini wheel but it doesn’t accept 2″ filters and weighs pretty much the same as the Midi anyway – 800gms or thereabouts.
The Trius 694 clocks in at 450gm. I doubt if the Lodestar guider makes much difference.
So the whole thing is a decent weight – which seems a lot at the end of a thin Newtonian tube. 🙂
I will try tightening the central screw by tiny amounts every evening and see how it gets on.
BTW the Midi wheel can take 2″ filters – it has two wheel options.
Our local sports field expressed a desire to be dark sky / wildlife friendly when they replaced their halogen tennis court lights. Unfortunately, the difference in quote for less blue lights made them unaffordable for a small sports club/charity. At least they tried.
However, it looks like the fitters are not aware of the idea of light spill and the field next door is illuminated directly over 400m away… Bizarre.
I am imaging JUICE at the moment and after stacking 5x 60s frames (aligned on the star field) I could see a hint of the track. As its a hazy night, that sounds like the bright end of 18th mag. Will do some proper sums tomorrow and post the picture.
Tonight it is 1.4 million miles away.
Time to break out Tycho tracker I think. Will be interested to see how far we can push things.
Just processed my results from last night. JUICE was at mag 17.3 using an unfiltered Trius 694 and Gaia g comparisons.
JUICE was SNR=15 in 30s exposures this evening – must get the OAG going again.
Have never really checked. Managed 20.4 with the 10″. Got a Z=5 QSO but the unfiltered mag of that was uncertain as a lot of the light was shifted into the red – am guessing mag 20.8. Suspect that on a good clear night with a high target and no Moon I am looking at 21. Would need to be an interesting target. 🙂
just did a quick unfiltered imaging estimate of the magnitude of JUICE around midnight 17/18th April and get 16.3 with a fairly steady value and a position that agrees with JPL Horizon at the <1 arc sec level.
Will try again tonight…
I can’t imagine what you mean. 🙂
I never quite established what it was the Avast had done, but it lost contact the moment it started its update. Took me 2 evenings to coax it back to life – worked fine via keyboard, but refused to talk over Wifi. Fine now…
I think its fortunate that I attended a failing North London comprehensive in the 1970s. It equipped me with the robust language skills I needed to properly describe exactly what I thought about the staff at Avast, the authors of Windows 10 and life, the universe and everything.
Lets just say …. I was somewhat vexed.
Were it not for an Avast antivirus software update knackering – in a very subtle manner – the ability of the observatory PC to talk to the house, I would have been imaging at the same time as you – before the mist started rolling in about 12:30. Looking at my post meridian flip image sequence, the stars are gradually fading as the transparency went to pot.
Will measure some brightness values later…
Currently looking at the location suggested by JPL Horizons and am really surprised by how bright this thing is for something man made half a million miles away.
And thats under murky conditions. Image at https://britastro.org/observations/observation.php?id=20230418_002705_da18d9fe717fc9b0
