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View Full Version here: : M20 (Trifid) and M8 (Lagoon) Nebulas - my best yet


iceman
18-03-2008, 10:06 PM
Hi guys

This started out as a quick run at the end of an imaging session while I waited for Jupiter to rise.. I saw M8/M20 was rising, only about 25-30deg at the time but I set up a run and went back to bed for a couple of hours until Jupiter was up higher.

It's only 42mins worth of exposure (7 x 6 minutes), but i'm really happy with how it turned out. I took a lot of time in processing this image, with a lot of selective processing, selective high pass filtering, selective levels and curves, etc. I feel like i'm finally starting to get the hang of this DSO stuff.

I used Jase's beautiful image (http://www.cosmicphotos.com/gallery/image.php?fld_image_id=99&fld_album_id=11) to guide me to know when I'd done enough processing :)

Unmodded Canon 350D + ED80 + WO 0.8x reducer. Guided with PHD + DMK. Darks with ICNR, flats calibrated in ImagesPlus.
Unfortunately the WO was not square or something, so there's horrible elongated stars in the corners.

Attached is a small version, but it's best to look at the 1200px wide less compressed version:

M20 (Trifid) and M8 (Lagoon) Nebulas (http://www.iceinspace.com.au/mygallery/displayimage.php?pos=-654) (Click the image to see the full size).

I really can't wait to give this another go at SPSP, when it's rising higher, under very dark skies, and I can give it loads more exposure time.

Thanks for looking.

citivolus
18-03-2008, 10:13 PM
To me the gamma looks a bit high and black seems to be a tad high up the histogram, but then I'm using an uncalibrated laptop at the moment.

If I were composing the shot, I think I would take the objects up just a bit in the frame. Left to right is good, as you don't want to lose the cluster. You seem to be using a good field size/focal length for this pair.

strongmanmike
18-03-2008, 10:56 PM
You've gotta be happy with that for an unatended image run, very nice :thumbsup:

I am too chicken to leave my NJP and AP alone while I sleep..I must be paranoid? I do go inside and surf the net but I have to check on things every 20min or so, even if just to check my subs for any errors that might mean I have to take another in its place..?.... :screwy: Seriously though without an accurately trained temp compensating focuser I get focus shift and I like to refocus every 30min, I think this ensures the highest quality focus throughout an imaging run.

The other night I must say I did 5 hrs of imaging on one object and the average dy/dx guide errors were around 0.15pix or +/- 0.3" the whole time!!...still checked on it and refocused every 30min or so though :P

Mike

EzyStyles
19-03-2008, 02:29 AM
great shot mikey. you must be happy with it. using the w.o focal reducer gave you such a widefield with the ed80? is it free of coma or did you cropped abit around the edges?

Geoff45
19-03-2008, 08:18 AM
I had the same problem when I used the WO field flattener with my ZS110. You get a nice wide field, but have to do a whole lot of work to round up the stars.

Nice pic to get these two together.
Geoff

davidpretorius
19-03-2008, 10:54 AM
very very pleasing.

WOW

h0ughy
19-03-2008, 11:42 AM
so where is the planet? LOL nice work Mike

Ric
19-03-2008, 12:41 PM
Lovely capture Mike, I always enjoy widefields of this area, they always make for a spectacular image.

Well done.

Garyh
19-03-2008, 02:56 PM
The large version looks beautiful!
great work from LP`ed Newcastle
:thumbsup:

tornado33
19-03-2008, 02:58 PM
excellent work there Mike. I will give it a go in a month or 2 when its higher, the east is right over inner Newcastle and heavily light polluted
Scott

Alchemy
19-03-2008, 05:51 PM
Nice mike, you are coming along well with the deep sky stuff, you must be happy with that one.:thumbsup:

jase
19-03-2008, 07:10 PM
Lovely Mike. Composition and processing look spot on. Well done.

Rodstar
19-03-2008, 08:21 PM
Now that is why the M8/20 area of the sky is my favourite out of the entire heavens!

iceman
19-03-2008, 09:54 PM
Thanks Eric, I agree about the composition. However due to the flattener not flattening, I had to be careful not to get the cluster near the corners.


Thanks Mike - I was like that to start with, but now I have to trust that it's doing the job properly. Once or twice I've woken up and come out to PHD guiding beeping at me because of a lost guide star due to clouds. But sleep was necessary after all those clear nights we had! Unattended imaging is perfect when it all goes right!


Thanks Eric, I'm very happy with it. Your DSLR shots are amazing motivation and set a very high standard to aspire to.
The W.O reducer/flattener gives me a focal length of 480mm (f/6) instead of the native 600mm. It's slightly cropped around the edges, but only to account for the slight rotation in each frame after stacking.


Thanks Geoff - the W.O can be very annoying. The first few times I used it I never had the seagull stars in the corners, now I get them often. I need to experiment more with placement, tightening of screws etc, to find the combination where it actually does flatten the field.


Many thanks Jase - and thanks for your brilliant image to use as inspiration and guidance while processing. I was trying to get more pink/red in the middle of the lagoon but I was wondering whether the lack of H-A in my captures was the cause - or just lack of exposures.


Thanks Scott, much appreciated. I'm really looking forward to giving it another go when it's up higher. I just couldn't resist it when I was looking for targets at 3am, to take me up to 5am when Jupiter was high enough :)


Thanks Alchemy, I am very happy with it. I feel like I actually know what i'm doing in processing now, instead of just adjusting levels and curves and hoping for the best :)


Thanks Gary. I'm actually south of Newcastle by about an hour. My east sky isn't too bad luckily. I've got Newcastle to the North, Gosford to the SouthWest and Sydney to the South so neither of those are great.


Thanks Ric - I was very pleased when I took the first test shot for composition and saw that they fit in the field.


It came later, I posted it in a separate thread. ;)


You're not wrong, Rod. So much going on. That whole area is new to me for deep-space imaging, so it's going to be like a kid in a candy store picking and choosing targets when it rises a bit higher.


Thanks for all your comments, much appreciated.

I've still got an Omega Centauri and NGC6231/surrounds to process.. hopefully soon!

Phil
19-03-2008, 10:05 PM
Wow Mike thats a grart shot.
Phil