NGC 1365 Great Barred Spiral Galaxy ( Re Processed)

[Startrek]

Starved of clear nights for a month , Friday night in Sydney presented a clear night with a 70% waning moon. Seeing wasn’t too good so picked an east broadband target ( only joking ) NGC 1365 a magnitude 10 Galaxy under Bortle 7/8 skies.At my image scale and FOV this Galaxy is tiny at 4 x 3 arc mins


Finished imaging at 3.30am

6” f6 GSO Bintel Newt
Skywatcher EQ6-R pro mount
ZWO2600MC cooled to -10C Gain 100
No filters
TS Optics GPU coma corrector
189 x 60 sec subs ( dithered every 3rd sub )
40 x Flats
60 x Bias
PHD2 Multistar guiding ( poor guiding at 0.70 to 0.80 total rms )
EQMOD, Stellarium, APT
Stacked in DSS
Processed in Startools V1.8 OSC linear data set

The LP and Moon gradient was ridiculous ( first initial stretch to inspect the data was almost a “white out” ( see attached photo )
Wrestled with processing to try and dampen and remove the noise without sacrificing to much detail

Initial Stetched image showing gradients
Final cropped processed image left in Synthetic Luminance ( I tried to process the chrominance or colour but the noise grain left red mottle throughout the arms so left it in Synth Lum

Comments welcome
Thanks

[Dave882]

Hi Martin wow it might be small but still quite an interesting target. You’ve done extremely well to walk away with something from Friday. I was trying to do some planetary imaging and although the sky was clear it was such incredibly poor seeing/transparency it might as well have been overcast. With such few clear nights recently we’ve got to make the most of what we have tho! Nice job

[Startrek]

Thanks Dave
Some may think it’s a waste of time or even foolish imaging OSC broadband on something so small and dim under Heavy LP with a less than suitable scope , but at least it’s a big challenge. Although still noisy I’m pretty happy with the end result. It keeps you interested
Id like to image this Galaxy down at my Dome under Bortle 3 with the 10”
Chalk and cheese between the two locations with equipment and conditions
La Niña is suppose to weaken towards January/ February 2023 , I hope their correct

Cheers
Martin

[strongmanmike]

Never a waste of time or foolish, an image is an image :thumbsup:

This is actually a bright and good sized galaxy though Martin, so a good choice under a bit of Moon, if (as I also did recently :whistle: :D) you feel so compelled :thumbsup:

According to NASA/IPAC Extragalactic Database, it's Magnitude is 8 in the visible I band and on the ESO-Uppsala "Quick Blue" IIa-O plate, its long axis is a decent 840.00" or 14 arc min! ...so it's a beauty and no wonder it is one of the few southern galaxies that shows clear spiral structure visually, in medium sized amateur scopes under dark skies.

Mike

[gregbradley]

Looks pretty decent. Any galaxy needs considerable exposure time even with new CMOS cameras.

Life would be easier for you though with a mono camera. I understand the allure of simplified processing with OSC but to get that next step up is going to require a mono setup.

Greg.

[Startrek]

Thanks big Mike,
Always giving encouragement, top bloke
On another note , ever tried imaging under Bortle 8 in Sydney’s filthy light polluted skies , it’s a battle that’s for sure with broadband

Cheers
Martin

[Startrek]

Thanks Greg
The same object , same OSC camera in my 10” Carbon fibre at my South coast Dome ( Bortle 3 ) would be a completely different outcome
Chalk and cheese
Mono would be so much better at either location too !!

Cheers
Martin

[strongmanmike]

Well yes, not from Sydney but inner Canberra city precincts and Newcastle city inner suburbs.

Back in mid 2006 I imaged from Campbell in the ACT for a short time, between house moves, we lived next to the Australian War Memorial so the skies were pretty light polluted but I still liked to get out with the Starfire APO and my Starlightxpress SXVH9 and do some short snaps, just for fun, here is a pretty lacklustre short snap of NGC 1097 (https://pbase.com/strongmanmike2002/image/68449717/original)

But this quick RGB only, snap shot (30min total exposure) of Orion's Sword (https://pbase.com/strongmanmike2002/image/139952692/original) was taken from light polluted inner suburban Newcastle in 2011, with my then new Orion Optics UK 12" F3.8 Newt and FLI PL16803 CCD, it come out surprisingly well for such a location!

Dark skies are much better for imaging, no question about that though and you can go reeeeally deep! (https://astrography.com/collections/michael-sidonio/products/michael-sidonio-centaurus-a-deep-field) :whistle:.....sorry :ashamed: :D

NGC 1365 is on my list of four potential possible full-on first light targets for Eagleview, depending on when (if?) the SE of Oz actually ever clears up for long enough :rolleyes:

Mike

[Startrek]

Mike,
Thanks
Top notch images !!
NGC 1365 amongst others are definitely on my list too from my South Coast Dome , nice dark skies and a substantially bigger mount and scope ( 10” Carbon fibre Newt on a EQ8-R pro )
Yep , can’t beat dark skies
BOM has La Niña weakening in a few months so a persistent cloudy east coast probably until the end of summer ……
When we finally get some consistent clear nights we will be all like shift workers doing the graveyard

Cheers
Martin

[oska]

Mate I like it, given how tragic the gradient was. You're too hard on yourself, any star time is a good time, like pizza.
So only a "few" more months then :rolleyes:

[Startrek]

Thanks John
Another few hours on this object would improve it some what but it’s certainly a battle dampening the noise whilst maintaining detail in post processing.
I spend twice the hours processing in Sydney than I do at my Dome down south under dark skies , it’s an absolute dream down there when the subs come in with dark background and so much detail , in Sydney when the subs come in it’s a heavy green cast background and not much detail on the object. This object was just a tiny small smear in the centre of the image ( which represented the core ) You’ve gotta have a keen eye to fine tune the centre these dim galaxies as you could easily mistake the core for small Star.

It makes the hobby more challenging, keeps you focused

Cheers
Martin

[Startrek]

Here’s a re process I did this morning watching rain fall through the window
Performed a tighter Crop and Binned to 60% ( greatly reduced image size with improved SNR )
Backed off a bit on the stretch to keep the noise down and reduced the gamma
Only a light sharpen and HDR
Applied the Super Structure module using Dim small and Brighten
Used the Spatially Variant Deconvolution with about 22 PSF Star samples
This time applied the Colour module with some success ( Scientific Aware )

Turned out better than I expected compared to the original

Comments welcome
Thanks

[pkinchington]

:thumbsup::thumbsup::thumbsup:

[Addos]

thats a very sharp result for the gear used, well done! don't worry too much about the gradient; you can only really improve on that from a bortle 7 with significantly more integration time. you've dealt with it very well in post :)

[Startrek]

Thanks Kanga 👍

[Startrek]

Thanks Adam,
Yes we can always do with more data no matter what we’re imaging
Cheers
Martin