Arp 77 - NGC 1097

[alocky (Andrew lockwood)]

This is a gem of an object, quite large and bright. I imaged this over four clear nights this week from suburban Perth through the 16" f3.6.
I was trying to image the 4 faint optical jets that come out of this, and although they are visible in the data - and if you know exactly where to look the brighter two are just visible, the lumpiness of the sky background due to the light pollution makes it impossible to present them in an aesthetically pleasing manner. However, the disturbed arm and companion galaxy, as well as wealth of detail in the core make this an interesting object even without the deep external features.
Link to the astrobin site here, as the thumbnail isn't particularly good:
https://www.astrobin.com/full/376987/B/
cheers,
Andrew.

[Placidus (Mike and Trish)]

Superb! Congratulations !!

We saw the brightest of the four jets (the one heading toward 10 o'clock and passing almost over a tiny edge-on spiral) pretty much instantly.

The detail in the core is wonderful.

Best,
MnT

[codemonkey (Lee)]

Great target this one and you have excellent resolution here; well done! I've been trying to gather data on this myself but so far I've only managed about 3hrs of bad data in poor seeing and a pier collision.

FWIW I think the image would be improved if you darkened the background a bit.

[multiweb (Marc)]

Really cool. Beaute details. Always enjoy seeing your galaxy shots Andrew.
Now I have a scope with a bit of FL it gives me something to look forward to.

[strongmanmike (Michael)]

The structures visible in the main hub of the galaxy are excellent Andrew, light pollution doesn't affect this aspect at least

Mike

[alpal]

Hi Andrew,
you've done well to pick that up with light pollution against you.
The blotchy background can be fixed up by adding noise in each separate RGB channel.


cheers
Allan

[Atmos (Colin)]

The detail in the core is excuisite Andrew!
With the background, that mottling appears to be caused by too much noise reduction, maybe not the amount but the scale used. A smoother less mottled noise reduction would improve the background but well done in capturing the jets, Placidus mentioned, one of them is very obvious

[keller60 (Bill)]

Apart from some noise, a great image from an urban location (?)
Bill

[alocky (Andrew lockwood)]

Originally Posted by keller60

Apart from some noise, a great image from an urban location (?)
Bill

Thanks Bill - Still some experimenting to do with the noise reduction, but I guess there are limits.

Originally Posted by Atmos

The detail in the core is excuisite Andrew!
With the background, that mottling appears to be caused by too much noise reduction, maybe not the amount but the scale used. A smoother less mottled noise reduction would improve the background but well done in capturing the jets, Placidus mentioned, one of them is very obvious

I'll revisit the noise reduction and see if I can get a better result as I know exactly what step introduced that.

Originally Posted by alpal

Hi Andrew,
you've done well to pick that up with light pollution against you.
The blotchy background can be fixed up by adding noise in each separate RGB channel.


cheers
Allan

I've seen that approach to filling in some of the black holes - might be worth a look.

Originally Posted by strongmanmike

The structures visible in the main hub of the galaxy are excellent Andrew, light pollution doesn't affect this aspect at least

Mike

Thanks Mike - I was lucky enough to get a good set of optics from ASA, so when conditions allow this system is pretty damn tight, although there's a slight egginess to the stars post stack that isn't in the subs - I might have to revisit the stacking.

Originally Posted by multiweb

Really cool. Beaute details. Always enjoy seeing your galaxy shots Andrew.
Now I have a scope with a bit of FL it gives me something to look forward to.

I look forward to seeing your images! Imaging galaxies less than 10km from a CBD is kind of fun, but one day I'll retire to the country and see what this baby can really deliver under a good sky.

Originally Posted by codemonkey

Great target this one and you have excellent resolution here; well done! I've been trying to gather data on this myself but so far I've only managed about 3hrs of bad data in poor seeing and a pier collision.

FWIW I think the image would be improved if you darkened the background a bit.

Black clipping's a bit of a trick - what looks great on an iphone will look grey on a properly calibrated monitor. The trick is to have a smooth enough background so the blotchiness doesn't show up.

Originally Posted by Placidus

Superb! Congratulations !!

We saw the brightest of the four jets (the one heading toward 10 o'clock and passing almost over a tiny edge-on spiral) pretty much instantly.

The detail in the core is wonderful.

Best,
MnT

Thanks Mike and Trish! I can even trace the dog-leg in that one on my monitor.

[RickS (Rick)]

A shame you don't have darker skies, Andrew, but the details in the core are fantastic!

[alpal]

Originally Posted by alocky

I've seen that approach to filling in some of the black holes - might be worth a look.

Hi Andrew,
It might be worth a try -
it's such a good picture of the galaxy that it's worth it.
However you can go further than the example below by
splitting into RGB & performing it on each channel separately.

see here:
http://bf-astro.com/backgndrepair.htm

"The following steps will make the background smoother
with little or no loss of faint galaxies!"

cheers
Allan