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Cygnus mosaic update - now 2x2 (Star 71)

Uranium235

By Uranium235
in Imaging - Deep Sky

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Uranium235

Uranium235

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Well.... havent we been blessed this week? :)

Three fairly good nights in a row has allowed me to expand on what I captured last time out, so its  now up to four panes with at least another 2 to go. I could just keep going and do the whole darn lot of it, but waiting until midnight for it to rise above the house means Im not getting much sleep! So im kinda glad im not setting up tonight as it gives me the chance to catch up on some much needed zzzz's, besides the conditions are rubbish anyway so I dont want to damage the image by taking any duff subs.

However, im still short by a bit on a couple of panes - the top right needs another hour so it matches the other three (need to chuck one or two because a neighbours washing line was in the way!), but it still stood up to the processing routines well enough with just 6x900s.

It probably needs another three or four sessions worth of data in order to get over to the Crescent and kill off any noise... and no, I probably wont be doing colour for this one...lol.. There just isnt enough darkness left to start an OIII cover of the area, and its only a few weeks before I get forced into my temporary Summer shutdown (well for night imaging anyway!). I'll probably end up switching to solar for a few weeks.

 

8x900 x3 panes + 6x900 1pane (Ha)

Star71, Atik 383L+, NEQ6

 

Thanks for looking! :)

26838595835_69b1dbc7ea_k.jpg

 

Pixel peepers and corner freaks version here:

https://farm8.staticflickr.com/7220/26838595835_844f20293e_o.jpg

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Uranium235

Uranium235

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Thanks guys :)

Ive been looking into how far this can be extended, and it is possible to take it over to the tulip - but that would be another 7 on top of what ive already done. Might be something to consider for the restart of the late summer/autumn season. But of course, the bigger it gets - the more difficult it is to stitch together.

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Tommohawk

Tommohawk

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Hey that looks really nice - loads of detail. Hopefully you'll find the time to add some colour sometime!

I had a go at a 6 pane Cygnus mosaic and really struggled to figure out how to centre the shots. The only mosaic I had done prior was lunar and that was easy to do just using liveview.

My Cygnus effort ended up as a 1 pane mosaic!

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Uranium235

Uranium235

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23 minutes ago, Tommohawk said:

Hey that looks really nice - loads of detail. Hopefully you'll find the time to add some colour sometime!

I had a go at a 6 pane Cygnus mosaic and really struggled to figure out how to centre the shots. The only mosaic I had done prior was lunar and that was easy to do just using liveview.

My Cygnus effort ended up as a 1 pane mosaic!

To plan this, probably the best (and free) way is to do it with Stellarium. Figure out where youre first pane will be, then work outwards by selecting a bright(ish) star near the edge of the frame to use for your overlap marker. A 20-25% overlap is about right, but you can cut things a bit finer if you need to (15%)... however that runs the risk of stitching problems or differences in background levels when data is shot over multiple nights. The most important thing is to have a flat field, otherwise you are relying on trying to find a flat (and large) enough "map" image to register your panes to using registar.

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Uranium235

Uranium235

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Thanks Michael :)

The plan is once I get the Crescent in, I want to get it put on canvas as a parting gift for our science lecturer who retires at the end of term - should be an interesting conversation piece for his wall at home!

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Tommohawk

Tommohawk

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26 minutes ago, Uranium235 said:

To plan this, probably the best (and free) way is to do it with Stellarium. Figure out where youre first pane will be, then work outwards by selecting a bright(ish) star near the edge of the frame to use for your overlap marker. A 20-25% overlap is about right, but you can cut things a bit finer if you need to (15%)... however that runs the risk of stitching problems or differences in background levels when data is shot over multiple nights. The most important thing is to have a flat field, otherwise you are relying on trying to find a flat (and large) enough "map" image to register your panes to using registar.

Yes - thanks for that. In the end I did try using stars from Stellarium as you suggest, but I couldn't find any quite where I wanted. I'm now downloading another catalogue which hopefully will help. 

PS hope the skies hold out for you to get finished by end of term!

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Uranium235

Uranium235

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Thanks, Im hoping Sunday night will give me a couple of hours to add another pane. As long as its done before the Moon turns up I'll be happy (moonlight usually plays havoc with background levels, even in Ha).

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AndyUK

AndyUK

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A fantastic project Rob - Not taking anything away from the other parts, but I particularly like the detail in IC1318... It may be my failing eyes, but I can't see any weakness in the top right, but if you say it's there, I won't doubt it!  I felt the same as you this last week - 3 days on the trot was really pushing it, especiially having to wake up every 90 mins to refocus.   I've been contemplating autofocusers and rain sensors this weekend!  I hope you get the final 2 panes soon though - It's superb now, but it'll be superb when its finished :)

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Uranium235

Uranium235

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11 minutes ago, AndyUK said:

A fantastic project Rob - Not taking anything away from the other parts, but I particularly like the detail in IC1318... It may be my failing eyes, but I can't see any weakness in the top right, but if you say it's there, I won't doubt it!  I felt the same as you this last week - 3 days on the trot was really pushing it, especiially having to wake up every 90 mins to refocus.   I've been contemplating autofocusers and rain sensors this weekend!  I hope you get the final 2 panes soon though - It's superb now, but it'll be superb when its finished :)

Thanks Andy :)  If you look real close in the top right area (in the fullsize version) you will see a few hot pixels floating about, thats where I didnt have a stack deep enough to eliminate them. Though I would expect that to improve once I get a few more subs on board.... speaking of which, tonight is looking clear! There might only be time for an hour or so, since its back to work tomorrow (boooo!).

Im surprised you had to get up and refocus mate, I did mine once (after an initial period of cooling) then didnt touch it again. Perhaps running the dew strip at full blast is keeping the objective at a steady temperature?

Once I have the other two panes I will work on getting the noise levels down so I can push the other parts of the image using layer masks so it brings out more of the knotty detail and the numerous bok globs dotted around the place.

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ollypenrice

ollypenrice

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That's a stormer!  Fascinating to see what's going on that side of Sadr and the Butterfly. I've done a big one going the opposite way. I often wondered where the Propellor was and now I know. I also spot a nebula which we might call the North America Nebula, Peeter's Projection. :icon_mrgreen:

What is there to say other than this is a splendid image, beautifully crafted.

Olly

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Uranium235

Uranium235

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Thanks Olly! I did briefly consider going the other way over to the North America, but its a stretch too far for me (so I'll do it separately). I'll aim for the Crescent first, and anything else after that is a bonus :)

 

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AndyUK

AndyUK

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Quote

If you look real close in the top right area (in the fullsize version) you will see a few hot pixels floating about, thats where I didnt have a stack deep enough to eliminate them.

... I try not to pixel peak any more... :).  Okay, I can just about see them, but even so...

Quote

Im surprised you had to get up and refocus mate, I did mine once (after an initial period of cooling) then didnt touch it again. Perhaps running the dew strip at full blast is keeping the objective at a steady temperature?

Well, I do use a dew-not strip, but I notice that my FWHM starts drifting after about an hour or so... and certainly if I leave it 2 hours, it could be out by perhaps as much as nearly 10% :(.  Still, that's getting off-topic...

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Uranium235

Uranium235

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1 hour ago, ollypenrice said:

AstroArt has a hot pixel filter which will zap the blighters and silence the pestilent peepers!

After the Crescent, the Tulip. You've started so you'll finish!

Olly

I've just checked out how much more I need to do in order to get that far.... oh dear... thats 12 panes more on top of what I have already done! It would end up being over 100mpx :eek:

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