Have a cigar...

[alocky]

This is an irregularly shaped galaxy that is commonly known as the 'cigar' galaxy. It is classified as a Magellanic type barred spiral, which puts it in the same kind of category as the Large Magellanic Cloud.
At 7.2 million light years (or 2.2M parsecs) it's not quite in the local group, but nor is it believed to be in the Sculptor group of galaxies. It's stuck somewhere in between, along with it's mate NGC300.

I took this with a streetlight shining into the telescope :-( over two nights through the 16" ASA.
Processed in pixinisght using the new funky-chicken local normalisation and drizzle integration, a smidge of decon, then photometric colour calibration and lots of stretching and masking to try and get the background not blotchy.

high res on astrobin here. Comments and constructive criticism are welcome!
http://www.astrobin.com/full/314169/0/

cheers,
Andrew.

[Placidus]

That's very fine, Andrew. The number of background galaxies with detailed detectable shape and structure is impressive.

[gregbradley]

Terrific image Andrew. Galaxy detail and colour look spot on. Only comment would be the relatively high background noise that could be reduced.

Greg.

[multiweb]

That is superb Andrew. Cooking on all 6 now. You've resolved many of the background faint fuzzies. :thumbsup::thumbsup::thumbsup:

[Peter Ward]

I feel your pain with the streetlight(s)...think I have about 4.5 million of the suckers to contend with....

Beautifuly resolved. Nice one:thumbsup:

[RickS]

Andrew,

I agree with Greg's comment that the background would benefit from a little clean up, but the galaxy looks great :thumbsup:

Did you find that LocalNormalization made a worthwhile contribution? I have tried it a couple of times on difficult fields with very faint detail and haven't been convinced it was an improvement.

Cheers,
Rick.

[Stevec35]

Given your conditions Andrew I think that's pretty darn good! Dare I say though that I think it's M82 in the north that's known as the cigar galaxy. Of course when I observed M82 many years ago I remember remarking that it looked very like NGC 55.

Cheers

Steve

[rustigsmed]

ouch! streetlights into the scope! you're game! but still good - nice one.

russ

[DJT]

That’s really nicely done. As Greg says, colours are spot on. Took a closer peak at the Ha areas and the dust areas in the galaxy and they are well resolved plus excellent stars.

Top job!

[Ryderscope]

The detail in NGC55 is very good David. This object can be hard to make to look good and you've done a great job.

[Atmos]

Detail and colour is very nice Andrew, echo the comments of others with the background noise reduction :)

[E_ri_k]

Great result Andrew :thumbsup: good detailed stucture visible in the galaxy.

Streetlight would have made you mad though!

Erik

[alocky]

Thanks Mike and Trish!


Thanks - there's a lot of really cool little irregular things hiding in there.


Thanks Peter! I thing your light pollution must be about double mine, I'm 10km away from the CBD, but it's not exaclty the same population!


Thanks Greg - as per my reply to Rick, the first night's data gave a better background, and I think I got too clever with Pixinisght!

Funny you should say that, Rick. The first night's data I processed without it and it looked a lot cleaner. When I combined both nights data I tried using it. Looking at the rejection images, it looks like it's doing a great job of eliminating all the local gradients, but the end result was a lot harder to get a nice stretch on. The background noise is as good as I could get it before a lot of localised blobs appeared in it. But in comparison, the first night's image had a much better background. I might try again without the local normalisation and see if that's why it went bad...

[alocky]

You're quite right! I've been calling it the cigar for years, but when I checked Hartungs, there's certainly no record of it having that common name. At least we can agree it's NGC 55 :)



You know it's bad when you have to set the scope up upside down so that the coma corrector doesn't have light falling directly on it :-(

[alocky]

The bloody thing actually went out for two weeks and I was hoping the weather would clear, but of course the grumpy, mean old neighbor over the road rang the council straight away and complained so they came and fixed it just before the clouds went away.:mad2:

[alocky]

Thanks Russ - it's the main reason I went for a dome, the observatory is above my garage and it is 10m away from a streetlight. I kick the thing every time I walk past it, glare at it, and have a bounty of a lifetime supply of beer for anyone who mows it down.

[alocky]

Thanks Colin, unfortunately, I think given the unevenness of the background caused by the light gradients means that's as good as it will get. Although I'll have another go at it.

Cheers for that! Although David's my brother's name ;)

[RickS]

Andrew,

I have since had some success using LocalNormalization on a fairly large amount of NGC7424 data. I had to push the scale up from the default and got best results using a DBE'd integration as the reference image.

You could always just nuke the background :) A careful mask and blur by removing a few small scale wavelet layers will do it!

Cheers,
Rick.

[Ryderscope]

Oops, :o

[skysurfer]

Nice picture !
I thought you were writing about M82 which is 'the cigar galaxy' in Ursa Major. But that is too far north (decl -69º) to be viewed from Australia.

[alocky]

Thanks also DJT and skysurfer - for some reason I can't quote either of your comments!
THanks also to Colin and Rick who provided some pixinisght insight. I've experimented a bit today with the local normalisation and have concluded that it doesn't add much when you have very blotchy and changing background gradients. Using TGV more aggressively and then the MMT to fill in the black holes using a luminance mask seemed to improve the background a lot. smoother and more clipped background version here!
http://www.astrobin.com/314169/B/

[atalas]

Very nice Andrew :thumbsup:

[Paul Haese]

Thanks nice detail in the galaxy Andrew. It's reminded me I really need to image this galaxy again.

[alpal]

Hi Andrew,
that's a great picture.
I wouldn't worry about the noise but I would say
that it's easy to process out with Photoshop.
Just making a mask & reducing the colour in the dark areas would go a long way.
You could even add noise in Photoshop in the same mask to make it finer noise & then a slight blur would nuke it.

Look at many Hubble images -
they don't care about the noise -
it's even more scientifically valuable to show where the noise floor is.

cheers
Allan

[alocky]

Thanks Louie!


Cheers Paul, what with 253, 55 and 300 all within a close distance it's easy to run out of clear nights!


Thanks Allan - I do like to see the noise floor too, as it means I haven't left anything there to squeeze out, and there's such a range in calibration of monitors as well. If I can see the noise on my PC monitors, I know most iphones and ipads will have a crisp black background. It's a personal choice, but I'm always willing to hear other people's views :-)

[alpal]

Hi Andrew,
I agree - too many photographers polish over their noise -
I prefer to see it - it tells me more.

cheers
Allan