Lagoon and Trifid

[KenGS]

We gt a rare clear couple of nights without a full moon last week. I realised I had last imaged these two way back when I did the M80 challenge on AF and only in mono. In fact I had misplaced those images so it was time to redo them.
Did M20 Trifid on the 10-August and M8 Lagoon on 11-Aug between around 7pm and 11pm
Details for both much the same:
60x60s on each of H, O, S with gain 139 and offset 50
RC8 with CCD47 reducer, Astronomik 6nm 1.25" filters, ASI1600MM-C running at -10C
Avalon M-Uno mount
All controlled through INDI and Kstars/EKOS
Guiding with PHD2 Z-filter algo, ASI120MM-S guidecam through OAG, 0.2s exposures, gain 10 (* due to latency in the driver this results in about 1s per exposure)
Seeing was not great on either night and there was some patchy high level cloud about
Flats, Darks and Dark flats stacked in DSS, saved as 32bit FITS and post processed in StarTools at 2x2 binning.
They might end up on a coffee mug

[MariusD69]

Great images! Well done, Ken! M8 is a good target for narrowband filters, but M20 not so much ( the blue reflection nebula and the dark nebula can't be capture well with these filters).

[BABOafrica]

Good to see you again, Ken.

I almost did not recognize the Trifid ... coloring and all.

So are you going to do the Messier Challenge all over again ???

BABO

[KenGS]

Good to see you again, Ken.

I almost did not recognize the Trifid ... coloring and all.

So are you going to do the Messier Challenge all over again ???

BABO

Nah, I'm just revisiting the more photogenic objects that I rushed through on the Mexsier Challenge.

[STEVE333]

Beautiful closeup details on both Ken. Glad you were able to get at least a couple of nights worth of data. Some of the nicest details I've seen on those two targets/

Steve

[yobbo89]

nice detail on the lagoon , especially in the core , probably a pay off from the shorter exposures , i always saturate this area .

m20 is certainly a narrowband friendly target, there are some traces of ha detail in the blue section of that nebula ''the reflection nebula'' but it does cut of alot of emissions while using a norrowband filter,it's best to image in rgb and do a mix blend of ha data to get detail out that reflection nebula


just a reference ,here is 16x 300 sec exposures with a more expensive filter ''chroma 3mm'' nether less the cheaper badder 7nm ha filter in the second image below does a good job aswell

i used an f4 scope with the same camera as yours ,bortle 6 , 5 min exposures same gain settings , you will really benefit going longer with exposures . i have no doubts that you can reveal that outer edge details with your setup and with some good settings,post processing.

[yobbo89]

I can see some outer region traces of ha data in your m20 image, but it looks like sky background is making the most of your image ie the green background glow, possibly from the oiii filter , is this in cfht pallet ie ha oiii sii maped as r g b ?

There are some tools that can help. scnr green removal is a good one , also it helps to indivualy process each b/w frame before combining and reduce that mid tone sky glow to a manageable level once the image is in lrgb combined.

sorry for getting in depth, i love to help people make the most of thier hobby and data .'

i enjoye the coffea mug image btw.

[yobbo89]

here is a little preview of the scnr tool, a few astro processing software have something simular .


star tools has a feature ,it's called cap green. see below

https://www.startools.org/modules/color ... ur-colours

(Cap Green
The 'Cap Green' parameter, finally, removes spurious green pixels if needed, reasoning that green dominant colours in outer space are rare and must therefore be caused by noise. Use of this feature should be considered a last resort if colour balancing does not yield adequate results and the green noise is severe. The final denoising stage should, thanks to Tracking data mining, pin pointed the green channel noise already and should be able to adequately mitigate it.)

[helicon]

Great Trifid capture - congrats!

[Gordon]

Congratulations Ken on having your image selected as todays TSS APOD!!!

app.php/article/8-17-2020-tss-astrophot ... of-the-day

[TheButcher]

Excellent images Ken and Congrats on the APOD!

[helicon]

Congrats on the apod Ken!

[Ruud]

Awesome work, Ken. Congrats on the APOD!

[Makuser]

Hi Ken. A great Trifid Nebula image, with lots of fine details. I always call it the "Scowling Cat", as it looks like my cats when they are not happy. Thanks for sharing your nice capture with us on here Ken, and congratulations on winning the TSS APOD Award today.

[KenGS]

Congratulations Ken on having your image selected as todays TSS APOD!!!

app.php/article/8-17-2020-tss-astrophot ... of-the-day

Thank you Gordon. That is a very pleasant surpise for me.

[KenGS]

here is a little preview of the scnr tool, a few astro processing software have something simular .


star tools has a feature ,it's called cap green. see below

https://www.startools.org/modules/color ... ur-colours

(Cap Green
The 'Cap Green' parameter, finally, removes spurious green pixels if needed, reasoning that green dominant colours in outer space are rare and must therefore be caused by noise. Use of this feature should be considered a last resort if colour balancing does not yield adequate results and the green noise is severe. The final denoising stage should, thanks to Tracking data mining, pin pointed the green channel noise already and should be able to adequately mitigate it.)

Thanks for the tips. Colour balance was a bit of a problem for me on this one. Light pollution once I get past the meridian is a lot worse.Plus I think I was underexposed on the S channel at least and noticed a lot of pixels clipped to black. Either that or its time to redo the darks.

[BABOafrica]

Congrats on the TSS APOD award !!!

BABO

[jthommes]

Great detail on the images. Nice work Ken.