Ouroboros

Thanks, @Padraic M.  That’s nice and clear. If I ever get round to doing that kind of thing I’ll have to work out how to do it with Pixinsight. 

7 hours ago, Padraic M said:

Thanks @Ouroboros. This was the first time doing this process and there is lots to learn. I'm surprised how much difference there is in the FOV given the pixel scale difference and the bigger sensor in the 1600MM. I'd like this to be a regular feature as I have the Esprit/1600MM setup in Dublin using narrowband to beat the light pollution, and the 150PDS/533MC is in Kerry under really dark skies, where OSC works well. I have both systems working reasonably well at this stage, so the thoughts of swapping the cameras from one to the other would fill me with dread! I'll need to do some more experimentation and see what works best.

Interesting. Do you have to rescale/resize the images taken with different devices, or does the software do that automatically?  And what about if there’s a difference in field curvature between different image sets? Is that taken into account too? 

@Padraic M Well done! Sounds like that was hard work.  I’m not quite sure what you’ve done exactly, because I only do OSC. Hoping to get into all that at some point.   The crescent nebula has been a particular focus of mine recently. It’s certainly a fascinating object.

Your stars have set off your Ha data very nicely.  Just a thought but it might also be good if you could capture some RGB star data to combine with your Ha data at the same scale.  You’ve picked up some nice Ha nebulosity in the larger Ha image.  

Superb! 

Nice. Yes, I agree.  Double stars make good images. Nice colours, @astro mick.  Where do the diffraction spikes in the second image come from? 

Totally agree with the securing cables thing. In my pre-ASIair days I’m sure most of the problems when I ran cables from a computer to various devices was due to cable stress. 

1 hour ago, bosun21 said:

I never ran my dew heaters directly from the ASIAIR plus. I found that it caused needless problems. Once removed to their own power source everything ran as it should. I'm 95% sure your problem is due to this.

On the other hand    …… I run my dew heaters from the ASIair with no problem, although I am aware of it being reported as a problem. I similarly run an ASI2600 and mini guide cam from the AIR, though no EAF.

Something I’ve just remembered is having similar problems of 2600 disconnects when running the camera at low temperatures when the ambient temp is quite high.   It’s fine on a cold winter’s night though.  It has been warm at night recently. Could try running it with the cooling off.

As others have said, dodgy USB cables is a possibility. Fortunately ZWO include two (long and short) so a swap might be easily tested depending on distances.

That’s quite a phew! things in your upgrade. 😀 Sorry if I’ve misunderstood your explanation, but did you try stripping right back to only running the ASI2600 from the ASIair - ie nothing else connected? See if that works. Then add other components one by one. You might also try running the guide camera as the main and only camera. I guess the thing to establish is whether this is an ASIair problem or a 2600 problem. 

A sample of Saharan sand washed down in this morning’s rain on the glass surface of a table in the garden.  

Oh, and I found a camel behind a rose bush. 

On 05/09/2023 at 16:11, Dark Raven said:

At the end I got fed up with it, not knowing if it will connect to certain device that night or not, wasted many clear nights freezing while trying to make it work. Went out and bought ASIAIR Plus, have not lost a singe clear night since, have not looked back or regretted it.

I am not fan of ZWOs closed ecosystem regarding the ASIAIR. Their stuff just works (for me, for now), and on seldom clear night that I can devote to this hobby I have no inclination to spend them troubleshooting drivers. 

I agree. Been there, done that, got the t-shirt.  Until recently (see below*) using the ASIair felt like coming home to something that simply works after years of flaffing around with control software/hardware that might work but often didn’t. 

* I do wonder now though whether ZWO have over reached themselves trying to make the AIR all things to all astronomers. It was fine until the recent updates.  Let’s hope it’s just a glitch. 

I’m almost relieved it’s cloudy tonight. I’ve had two nights out late under clear (ish) Cornish skies.  It wasn’t good enough for  imaging - too hazy and what with the Moon - but it’s been so warm it’s been a real pleasure just to observe. I set up my guide scope camera as the main scope and used my ASIair to act as my mount controller to do some  visual with my 200p Newtonian. First time I’ve tried doing that. I usually just use the ASIair for imaging. It’s good using plate solving to make sure the scope is actually pointing at the right thing to observe. Saturn looked great, as did Jupiter. Uranus and Neptune both showed their characteristic blue. Looked at several globulars - M13, M92, M2, M15, M56 and a couple in Delphinus. Looked at some  doubles too. The double double in Lyra, gamma 1 & 2 in Delphinus, Albireo, omicron 1 in Cygnus and a few others. M31 inevitably. Ring nebula. Triangulum Galaxy. Bit of a tour of the sky’s tourist spots really. 

 Welcome.  I suppose it’s true to say we meet up in virtual space ie here!  😃

4 hours ago, Mr Spock said:

Note, especially, that the meaning of “theory” in science is different than the meaning of “theory” in everyday conversation.

Exactly.  This alone is the cause of much misunderstanding in the public imagination about science and the nature of scientific knowledge. 

That’s a really interesting and eye catching image. 

I prefer what to my eye looks the more natural colour in your image, @mightymonoped.  It inspires me to have another go at the Triangulum this Autumn.

I daren’t reduce my sub durations given I use a 9/10 year old MacBook. It can take over night now to run a full calibration and stacking in PI for 2 minute subs.  Rather reluctantly I’m thinking of an upgrade to a new MacBook with M2 processor. 

Picking up on some of your comments, @windjammer, I’ve had another go. I went right back to an earlier image just after stretching to non-linear.  I applied some TGVDenoise to the starless image. Then used curves and colour saturation followed by a bit of local histogram equalisation.  I combined the image with the stretched star image in pixelmath. Finally I used Bill Branshan’s star reduction script to dial back the stars. I could even apply a few more iterations of that I think. Anyway, I’m happier with the result. Cheers.

2 minutes ago, vlaiv said:

Ok, so here is something very interesting.

People have an issue with the idea that everything came into existence at one particular time, but alternative is that everything existed infinitely long - it was never created it just existed without beginning, and that is perfectly fine?

Good point. Both possibilities may present conceptual difficulties. 

My goodness what a splendid image.  You only get to appreciate the grandeur of the veil by seeing it an image on that scale.  It’s not really very much data is it, if I understand your exposures properly. I guess this is down to the fast scope.  

Are there any viable alternatives to the Big Bang theory? I am aware of the steady state theory for example. A perfectly reasonable theory, but one not confirmed by current observations of the universe.  But are there any others? 

20 hours ago, windjammer said:

ps:  star field mismatched with nebula: I took your xstars nebula but redid the star mask from your first image: but not the same image dimensions!  Anyway, ideas to work with!

Sorry for delay in responding.  Busy yesterday.  Thanks for having a go at my image. Yes, the  images posted were screen shots and weren’t matched in size. You’ve done a good job in showing what’s possible, and certainly much closer to what I’m aiming at. I just have to work out how to do that in Pixinsight. Essentially it looks like you’ve done something like I was referring to earlier - retaining the brighter stars whilst suppressing the carpet of fainter ones. I’ll have another go later. 

15 hours ago, windjammer said:

Stars are too prominent in the final mix?  The xstars and starless look good as you say (xstars a bit noisy?) I don't use PI except for the basics, so would combine xstars and starmask in Affinity Photo - the blend mode of the layers would be 'screen' or 'add', with live adjustment layers (levels, brightness/contrast etc) on the star layer to turn them down a bit - judgement by eye!  Not sure what the pixel maths for that would be!  

Simon

Thanks for your comments, windjammer.  Yes, I think maybe I’ve over stretched the nebula given the quality of the data.   I should probably back that stretch off a tad. I have also been experimenting with adding or stretching the stars in different ways. Simply adding fainter stars (xstars + 0.2*stars for example) doesn’t look right. What looks better is stretching the stars to keep the main stars bright whilst suppressing the carpet of fainter stars.  The question is how to do that successfully? So far I’ve tried using curves with some success. Unfortunately, suppressing the faint stars also truncates the halos of the bright stars which gives them a slightly odd look.

I have been wondering why this image looks so poor given the reasonable appearance of the separate images: starless nebula and stars. 

I have recombined them using the formula ~{(~starless)*(~stars)}     I read this is supposed to give a better rendition of colour compared with a simple addition of images in Pixelmath.   Any thoughts on this? 

Here are screenshots of separate images:

1. starless

2. Stars

3. Zoom in on stars.  Quite nice I think.

Thanks, @Elp.  There appears to be a third option in that for some power line adapters the second adapter is also a WiFi extender. 

22 hours ago, Elp said:

Best ones are powerline ones if you can't run long ethernet cables.

OK. I assume that is used to get the home internet to a 13A socket close to where the telescope is set up outside. And then presumably either an ethernet  cable is used to connect the power line adapter to the ASIair or over WiFi from the power line adapter? 

Not my best effort, but it is my first (ish) light with my new AM5 mount.  Taken with ASI2600 on my SW Evostar ED80. 

This was the first proper imaging run with this mount. I’d done a few test runs with it previously. I’m happy with the guiding. It’s a very nice little mount …. and a joy to carry outside and set up. I’ve had a few issues with my new ASIair and getting the mount and Air to play nicely, but I won in the end. For now! We all know that when the gremlins go away that they’re only hiding temporarily!  

Anyway, 41 of 60 x 120s subs were good. Cloud clobbered the rest.  Processed in Pixinsight.  Cropped, DBE, SPCC, , BlurXTerminator, NoiseXTerminator. Used StarXterminator to split stars from nebular to process each separately.  Applied General Hyperbolic Stretch to both. Tweaked with curves etc. Recombined with Pixelmath.

I’ve tried to reduce the star content of the image but it tends to look a bit insipid if I do that. I don’t think there’s enough nebular data to stand on its own.