Iris and Ghost stitched together - Work in progress(?)

[Stefan B]

We had a stretch of clear skies which allowed for a more ambitious project. Although the first two nights still had a pretty bright moon (~70%) I aimed for dark nebulae in Cepheus. I always admired the images of the Iris Nebula or the Ghost Nebula. Some years ago I saw that they are actually very near to each other and together make for a great image. Unfortunately my FOV is too small to cover both in one frame. So I tried to do a small deep sky panorama by stitching two stacks.

Within six consecutive nights I was able to gather 20 hrs for each target. Unfortunately ASTAP somehow didn't stitch the images (well, it said it did, but I only got a black image with 300x300 pixels back...already asked Han about it). So I tried to process both stacks separately and stitch them with MS ICE. And surprisingly it wasn't even that bad:

It's an image I am not quite sure about. Too busy? Should I tone it down? Has the Iris still some gradient left?

Feedback is welcome. Here's the astrobin link, it's in the staging area at the moment: https://www.astrobin.com/501bp1/

Hope you had some clear skies, too!

Regards
Stefan

[dx_ron]

That's really nice. 40 hours over 6 nights! wow. I'd be a wreck. I sleep while imaging - just not very well and 6 consecutive nights of self-inflicted crappy sleep is too much for this old fart.

Too busy? Not possible, in my opinion. All the dust, all the stars, all the nebulosity - it's a busy, busy part of the sky. Your stars are really nicely controlled, totally unlike my bloated 60mm doublet stars from my Iris/Ghost image while back. Not to mention that I had to drive an hour each way to collect my ~10 hours total from a B4 site.

[fmeireso]

yeah it is nice image and what an achievement.Much detail and nebulosity. I don't even consider stitching an image let alone to know what and how software to use.

Integration time is remarkable. Me too i had to give way after 3 nights, can't bear to loose that much sleep.And i don't even image after 02:00 hr AM inmost cases, seldom until 03:00 AM

Well done Stefan!

[Stefan B]

Thanks, guys!

Yes, with regard to sleep it has been an interesting week. I don't sleep well until the meridian flip is done. Afterwards, it's quite fine. And fortunately the flip was before midnight and I wake up at 6 am, so it's been at least more than 6 hrs every night. But have to admit that the last nights I already was dead before the flip The last night we also had a party with >30 guests at our home...but we are here in Bavaria and everyone was busy drinking beer so nobody noticed that I've been away for 15 minutes to focus the scope and start imaging

Not to mention that I had to drive an hour each way to collect my ~10 hours total from a B4 site.

Well, that's dedication I never drove more than five minutes for imaging.

Concerning the image I guess I am pretty happy with it. Having looked at it on several screens now I even consider to brighten it up a bit, maybe using the skyglow parameter in Filmdev.

What worked really well was using the HDR module. The Iris has quite some dynamic range and HDR helped with revealing some details. I even increased the sliders instead of throttling them down as usual.

Regards
Stefan

[fmeireso]

Is your flip fully automated Stefan? I never bother...i just go back to zero pos once the object has passed to meredian. And then back to the object, plate solving once or twice perhaps, and i am again ready to go...I do this from in the house, i don't go outside for it ,normally...

[Stefan B]

Yes, it's fully automated and it worked every single time during the six nights. But of course I could do it manually like you said but just in case I would miss the right time to do it (because I sleep e.g....) the automated meridian flip is activated.

I don't sleep bad before the flip because I fear it won't work but just because I know I have to get up again. I don't have a wifi connection to my imaging notebook so I have to actually go there...but much more comfortable compared to driving an hour AND I get to see a nice night sky usually in the middle of the night

Regards
Stefan

[Mike in Rancho]

Nice job, Stefan! You're really on a roll lately.

I've neither fully automated my capture, nor ever set up in a dark site. I always stay up and keep an eye on things. I suppose I could sleep through. My yard is all walled and fenced so is reasonably safe. On top of that I have extra fencing and netting around the whole thing to keep my cats in, and it does reasonably well at keeping intruder critters out too.

I also only have AC plugin capability, so would need to set up some kind of power station, or be able to run my inverter generator. Now, I suppose I could fit everything in my little truck, but would probably have to make up some kind of boxing and protection for stability during travel. Ah, just easy to stay in the backyard...

I've tried this target a couple times myself, neither of them with much integration or frankly any good. But I can squeeze both main objects into one field of view! The dust makes this a really hard one for me.

The stitching, which I assume here is side by side the long way, makes for an interesting aspect ratio. Personally I'd say the brightness is appropriate, but that's a matter of taste for you. It's likely I would actually take this and run it through FilmDev to push things back a wee bit with gamma or just DAF.

Mosaics stitched post-processed can be really hard, and you did it quite well. ST is just always dynamic to the data, so matching everything up when ST has no knowledge of the other panel is no simple task.

The only thing I might look into, other than the fact that it's flipped "wrong" , is whether the seam region is visible. It almost seems there might be a line that bisects vertically just to the right of center, between the red and two blue stars. Maybe that's real structure though? The other thing I was thinking was, if not the actual seam (which I presume might be dead center), is that perhaps Wipe edge behavior settings on one panel could cause that?

Or maybe I'm just seeing things.

[Stefan B]

Nice job, Stefan! You're really on a roll lately.

Thanks, Mike! Yes, I try to use all the clear skies I can get. In 2022 my last image was in September and the next one in February 2023, I guess. Weather then has been relentless and fog season is probably starting soon. It's so frustrating if the forecast says it'll be clear and you're imaging for half an hour and always fog appears... I already saw the first fog in morning...

The stitching, which I assume here is side by side the long way, makes for an interesting aspect ratio.

Yeah, I also like that. If that's what "interesting" means

Mosaics stitched post-processed can be really hard, and you did it quite well. ST is just always dynamic to the data, so matching everything up when ST has no knowledge of the other panel is no simple task.

That's exactly the reason why I thought that this would never ever work. Actually the two images weren't even meant to be stitched. I just processed both stacks separately in order to get to know the data and how it behaves (and the individual images are of course smaller and processing is faster). Just after stitching the linear stacks didn't work I tried using ICE. It maybe shows that my processing workflow is a bit habitual ... routined...or consistent if you want to put it more positively

The only thing I might look into, other than the fact that it's flipped "wrong" , is whether the seam region is visible. It almost seems there might be a line that bisects vertically just to the right of center, between the red and two blue stars. Maybe that's real structure though?

Oh, could you maybe draw an arrow or something to it? I can't spot it. But this region corresponds to the overlap of both images...so you might be right. I compared the dust structures etc. with reference images (which weren't stitched) and thought it looked surprisingly good.

Regards
Stefan

[Stefan B]

other than the fact that it's flipped "wrong"

Forgot to adress that one That means you would rotate the image by 180°, right? Because of the Iris? I totally see your point then, but I wanted to the Ghost to be oriented the way it is. And that was more important to me than the orientation of the Iris Nebula.

Interesting how one can get used to these orientations even if they don't mean anything in space...

Regards
Stefan

[decay]

s whether the seam region is visible. It almost seems there might be a line that bisects vertically just to the right of center, between the red and two blue stars. Maybe that's real structure though?

Oh, could you maybe draw an arrow or something to it? I can't spot it.

Of course, I cannot speak for Mike , but I too saw this before Mike mentioned it:

2023-09-14 16_55_43-Iris and Ghost stitched together ( Stefan Böckler ) - AstroBin – Mozilla Firefox.jpg (117.15 KiB) Viewed 9241 times