NGC 3718, NGC 3729 and Hickson Group 54

[swag72]

This is the target I have been working on now for a few nights, yet still have a lumpy background and need more data for the spiral arms

NGC3718 is a warped spiral galaxy found in the constellation of Ursa Major. This galaxy pair (NGC3729 on the right) lies approx 52 million light years away. Hickson Group 54 can also be seen clustering above NGC3718, consisting of 5 interacting galaxies, it is just over 400 million light years away.

T: SW 120ED

M: HEQ5 with EQMOD

C: Atik 314L mono

F: Trutek filter wheel with Baader 1.25" filters

Stacked in DSS and processed solely in Pixinsight. I have 5 hours of Luminance that I didn't use, so perhaps I'll just stick with RGB in the future! If I could just sort out that background!

38 x 300 R (190 mins)

42 x 300 G (210 mins)

43 x 300 B (215 mins)

25 x flats for RGB, bias and darks.

[cloudbuster]

Looks good to me sara!

[Zul]

Very nice!!

[swag72]

Hi Both - Thans for looking and commenting. It's probably the best I've managed yet - Lesson to self, get more data!!

[ncjunk]

Great image you can see a lovely stream of stars flowing out from the Galaxy.

Very nice.

Enviado desde mi GT-I9003 usando Tapatalk

[nytecam]

Fabulous image - Hickson's are great for mindgames - have you tried HGC 50 @ 2BLY [=faintest Hickson] ~25' Sf M97 [Owl]

[RobH]

Great result Sara.

An interesting target well captured with fine star colour.

It looks like you've overdone the noise reduction on the background a little, but having imaged this a couple of years back, I understand why as the tails on the galaxy are very faint and need a lot of imaging time.....my version also has a problem with the background that occured when stretching the image hard.

Cheers

Rob

[alpal]

That's a very nice photo on a tough target.

I think that you could get more out of the data with careful processing.

Maybe if you publish the stacks someone could have a go & obtain better results?

[johnrt]

Ah ha! Looking very nice indeed!

Sarah, did you use the ACDNR noise reduction in PI? I find this always makes the background lumpy. The alternative is to use the Atrouswavelets for noise reduction. I'm sure Harry did a video on it.

I'd like to see the version with Lum as a comparison.

[swag72]

Cheers All, Yes I did use the Atrouswavelets for noise reduction first, but I found then that it gave funny results to the histogram stretch and also the histogram wouldn't move at all - So I couldn't do anything with the dark slider - Is this normal?

I think I just need more data!!

[RobH]

More data for sure Sara.....I need to grab more for this target too...It does need lots and lots of time.

You have quite enough RGB though.....in this case, I think that your time should be spent on luminance subs of 10 minutes or more.

Your luminance looked fine....why haven't you used it?

Rob

[swag72]

I'm sure it's my processing, but when I added it, nothing really happened - I did bin the stuff that you saw and got another 4 hours or so. I thought I may go down the RGB route instead - Seems easier (if anything is easy in this hobby!)

I don't really know how to best process the RGB to then get the best out of the luminance. I know that people have posted many ways to do it, but that all uses PS and for the life of me I can not translate PS speak into PI speak. So I thought that as I can kind of process RGB to stick to that instead. I really can capture just RGB can't I? I don't need luminance?

[johnrt]

No doesn't sound normal at all??!!

Have you applied the Lum via the LRGB combine tool? Process RGB & Lum separately (DBE, stretch, other stuff to taste), then combine them - move the saturation slider down to about 0.20 to increase the saturation and check the chrominance noise reduction box.

As per usual Harry has a video

Cheers All, Yes I did use the Atrouswavelets for noise reduction first, but I found then that it gave funny results to the histogram stretch and also the histogram wouldn't move at all - So I couldn't do anything with the dark slider - Is this normal?

I think I just need more data!!

[swag72]

I watch Harry's video's endlessly!!!

I will go back and watch them again!! I am trying to work out an order to process - When do you do the star reduction John? At what stage in the processing? I think I've probably got my order of stuff wrong!!

[RobH]

I know that people have posted many ways to do it, but that all uses PS and for the life of me I can not translate PS speak into PI speak.

I'm the exact opposite....PI is far too mathematical for me.....I like the organic PS route, and use layers all the time!!

Still....I'm going to keep bashing away at it and maybe my thick head will understand it one day

Rob

[Tim]

That's a great image Sara, no matter what you think

Tim

[AndyUK]

As I was away for the weekend, I missed the unveiling of this one - It really is a lovely object and I love the colour! A really nice result . I'd love to have a crack at this myself, but I've decided that my MN190 needs a minor overhaul... (Now there's an invitation for some clear skies to appear!)

[swag72]

Cheers Tim and Andy - I have since had the data processed by one of the PI developers and while he dealt with the noise far far better than me, the galaxy was very similar. So, I think more data is on order. Who can believe that 10 hours isn't enough?