[AstroFest] The tale of two nebulae

[Camelopardalis (Dunk)]

Folks, I know I said I was scraping the bottom of the barrel before, and I really didn't think this one would give much but this one positively surprised me In my efforts from suburban Sydney before I hadn't knowingly caught the colours of the star clouds that are starting to show in this shot, and the detail in the nebulae also really starts to be coming out now with a few photons on the sensor. I'm pretty happy with this, but always happy to improve and learn

This is with my little WO Zenithstar 71 (+reducer/flattener) on EQ6 and an unmodded Canon 1100D recording the photons...ISO1600 60x 1m exposures (I'd tripped over my tripod and couldn't get my drift alignment very good ), with biases and 20 darks.

There's a few Mr Blobbies in there...any tips how to de-blob them, or give them diffraction spikes or something else to make them less offensive? I've already used a star mask to keep most of the stars under control while I stretched the nebulosity out. But that skill terminates here Can I just go through the motions with that process again and just select the biggies?

Suggestions/tips always appreciated

[raymo]

Hi Dunk, I can help you by praising your work, but have no idea how
to reduce blobbies. Looks good.
raymo

[Camelopardalis (Dunk)]

Thanks raymo!

So far I'm liking it, it's made it to my inner circle - those that I might use as wallpaper it's tiny image here, JPEG compression is horrid with all those stars in the field, but it looks OK IMO up to desktop sizes (about 1/4 of the native pixel area)...not the greatest, but it's a start!

[BruceG (Bruce)]

Hey Dunk - that's a great capture! I really like the image, both composition and natural colour balance. You're right - one for the desktop background or one for the digital photo-frame to impress the relo's.
Keep up the good work - shows what you can do through Sydney's soup.
Just wish the clouds will go away this weekend, I really want to have a crack at the Helix on Saturday night.

[Camelopardalis (Dunk)]

Thanks Bruce! Yeah it would look better on the digi frame, lower resolution and all

Sadly though, this was taken from Astro Fest up at Camp Duckadang, QLD. I have looked at the set I took from Sydney and the biggest difference seems to be in the number of background stars...but then I had fewer subs from home.

[cometcatcher (Kevin)]

That's an excellent image Dunk. Gotta be happy with that.

Do you have an Astrobin account for a bigger image?

[Camelopardalis (Dunk)]

Thanks Kevin!

I don't use Astrobin, but I'm thinking of a solution for my larger files

[Camelopardalis (Dunk)]

Another of this pair, inspired by Barry's recent posting of multiple data sets (no doubt other folk think nothing of doing this, but it's been a bit of a day!), and I realised I had some data that I'd collected here when I was experimenting a couple of months back and a few other random subs from AstroFest...

Not convinced what it brings to the table, but all in it's added an extra 30 minutes of data to the stack. The only problem being the images were taken in different orientations, so to avoid the nasty border in the stacked image I've had to do some pretty severe cropping...I don't really like the outcome from a framing point of view. But I'll look into a way of smoothing out the edges and see if I can open it up somehow...would feathering work on a star filled edge?

[raymo]

Great stuff.
raymo

[Camelopardalis (Dunk)]

Cheers raymo!

[cometcatcher (Kevin)]

Originally Posted by Camelopardalis

... The only problem being the images were taken in different orientations, so to avoid the nasty border in the stacked image I've had to do some pretty severe cropping...I don't really like the outcome from a framing point of view. But I'll look into a way of smoothing out the edges and see if I can open it up somehow...would feathering work on a star filled edge?

I crop off the overlapping edges. I don't think they're salvageable.

[Rex]

Wow Dunk! That is an awesome image mate. I too love the composition and colour balance. Not sure what processing software u use but u may be able to combine using a ma imum setting instead of average. This way it takes the maximum value for each pixel which may help aleviate the stacking artifact from having different orientations. This may work but sometimes can result in a lot of noise. Worth a shot though.

[Camelopardalis (Dunk)]

Thanks Rex!

Another day, another repro

Here the images were stacked using intersect mode in DSS. Also I found an issue with my bias frames...I had divided the bias frames across the appropriate light groups, but for some unfathomable reason DSS is refusing to load the bias frames for one of the image groups (and I know the files are fine as they work OK in a stack of the lights and biases by themselves). It's almost like it doesn't want to load any more files anyhow, I cheated and divided the bias set from another group and it allowed me to add them. Weird.

Anyhow, the end result from the intersection stack isn't so awkwardly framed IMO, I can live with it This has been tretched to bring out the nebulosity and the colours almost brought themselves out, maybe just a little teasing. There's a tiny green problem on the RHS of the image and I'm not sure why. I don't remember seeing green stars, but maybe it's some green-channel shifting artefact from stacking. Dunno.

[Camelopardalis (Dunk)]

Originally Posted by cometcatcher

I crop off the overlapping edges. I don't think they're salvageable.

Yeah that's what I'd done previously. I switched the stack mode to Intersect and weirdly the image came out the end wider than the previous one

[Camelopardalis (Dunk)]

So these yellowish stars in the upper left corner... is this for real or is it a colour issue I've got? Other pics I've seen of Milky Way areas can take on the goldy hues, but I've not paid enough attention to other wide angle shots from this particular area

[cometcatcher (Kevin)]

Originally Posted by Camelopardalis

Yeah that's what I'd done previously. I switched the stack mode to Intersect and weirdly the image came out the end wider than the previous one

I didn't know about that. I'll have to try it if I need to widen the image.