Southern Spiral Galaxy NGC1672 repro

[gregbradley]

One of a series of galaxies I am imaging at the moment.

TEC180 fluorite (I forgot how large this scope is - impressive).

SX694 camera.

From my dark site observatory. 6 hours and 40 minutes.

http://upload.pbase.com/gregbradley/image/153979304/large

Here's an inverted view showing the extended spiral arms and the distortion to the main body down the bottom half of the galaxy. There seem to be a few extended/distorted spiral arms to this galaxy.

http://upload.pbase.com/image/153979775

Greg.

[RickS]

Great to see lots of unusual galaxy targets being imaged. That's another really nice image and another odd galaxy, Greg!

The Hubble images show a Seyfert galactic core that looks a lot like NGC 1097. Would be interesting to see if you can bring that out with more data or heavier handed processing.

Cheers,
Rick.

[strongmanmike]

Ahhh... great minds think alike....:whistle: ;)

Nice result Greg, good to have dark skies huh? Looks like that's a good combo of scope and camera, probably better than the H694-CDK even?

Mike

[gregbradley]

Thanks Rick. Not sure if I'll add to it. I may. I have several other targets I'd like to get done as well.



I see you must have been imaging this one as well. Yes the 694 and TEC180 work well together. A bit of struggle with the bright stars though. I am getting a halo effect. Not sure if its the flattener (which most likely is not needed with this scope) or the camera.

Its a better image scale and almost perfect sampling for the seeing here.

Greg.

[gregbradley]

I did a repro on this one to bring out the core in better colour and an overall more contrasty look with less colour boost that enhances too much noise.

Greg.

[RickS]

Nice improvement, Greg!

[tilbrook@rbe.ne]

Wonderful image Greg!:thumbsup:

It has a soft glow to it, really like this look.
Good to see these less imaged galaxies.

Cheers,

Justin.

[strongmanmike]

Yeah nice Sidonio'ing there :P and looks better :thumbsup:

Mike

[gregbradley]

Cheers Rick. As you know I am likely to do up to 30+ versions of an image until I am happy!!



Cheers Justin. Yes the less imaged galaxies hold an appeal.



Thanks Mike. Your image helped there.

Greg.

[Bassnut]

Suffers a bit by monster stars, lack of FL and a bit of noise. Is the Sidonio only on the thumbnail or also on the 1st link now?. Could you post thumb nails a bit bigger in the future?.

[gregbradley]

I personally quite like the focal length myself as it gives some space around the galaxy but I also like the long focal length look as well I get from the CDK.

The large stars are a concern. I am getting some bad halo effect with this camera on that scope and also to a much lesser degree on my CDK.
Perhaps its the small wells, perhaps the CCD window needs an anti reflection coating. I am planning on removing the flattener to see if that handles that issue.

Yes still some noise that another 5 hours probably would handle. depends on the weather gods at the moment. I post thumbnails usually just under the limit of 200kb. Perhaps I can compress a larger size more.

The repro is on the first link which is my usual way of doing it.

Greg.

[Ross G]

Great looking galaxy photo Greg.

A new object for me.

I like the composition..it does have a nice "glow".

Ross.

[stevous67]

HELL! That would be a whopper! :eyepop:

It's no doubt an interesting little galaxy. Very nice.

Steve

[gregbradley]

Thanks Ross.
I notice most of these galaxy images with the TEC180 have a glow about them. Perhaps its that last bit of light the fluorite passes through that helps.



I'll take a photo of the rig and post it tomorrow. I have to move my computer table rapidly sometimes otherwise the camera can hit the laptop!!

Greg.

[David Fitz-Henr]

That's an interesting galaxy Greg and showing some nice detail as well. Maybe needs a bit more work to suppress the colour noise but otherwise very nice. I'll be interested to see some pics of your setup as well, the TEC 180 sounds quite impressinve!

[gregbradley]

Thanks David.

Its always a battle to balance noise, brightness and colour. The only real solution is megadata or larger aperture. I worked it out Mikes 12 inch astrograph has 75000 mm2 in clear aperture roughly and the TEC about 25,000. With the TEC and this camera megadata is probably only about 10-15 hours but given the vagaries of weather and travel its quite an investment in time. My home site its much easier to do longer hours. Target selection comes into it then as well with the smaller dimmer targets not ideal because of the 10 hour requirement which depending where they are is probably 3 nights of imaging. I think I could work out a rough scale of length of time needed for the given brightness as listed in the Sky. Mag 10 galaxies take about 8-10 hours, Mag 9 about 6 or 7, Mag 11 about 10-15 and Mag 12 may not be worth it and need larger aperture and 20 hours. Of course any image benefits from more exposure time. A balance between many factors is practical though. Some images don't look that great no matter how many hours you do. So target selection is critical to see if its worthwhile or not.

I took a photo of the setup yesterday and I'll post that once I download the latest Lightroom which handles the Sony A7r.

Greg.

[SkyViking]

Great shot of this overlooked galaxy. I like the colours and overall image scale.
I'd agree with you that the huge stars do detract a little, but that's a minor detail. Great to see so many rare galaxies getting in the spotlight lately. Thanks for the view.

[gregbradley]

Thanks Rolf. Yes the overall performance of the scope is impressive - 7.5 inch APO picking up that much light and detail in "only" 6 hours 40 minutes. I am working on the star problem. I am thinking of installing a black cardboard baffle over the ccd window to see if that makes any difference. Perhaps flock the insides of my adapters. As usual the technician hat of this hobby is now on and I will sort it out one way or the other.

Greg.

[marco]

Really nice one Greg, I love these unusual galaxies being imaged! I find the image a bit soft, perhaps due to some noise reduction routines?
Color balance is great, with vibrant hues as I like :thumbsup:

Clear skies
Marco

[gregbradley]

It is a tad soft Marco. There is minimal noise reduction but there is some.

The only solution is longer hours and less noise reduction and more sharpening. Its also quite a small galaxy so I am happy with that as well.

Greg.