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I couldn't believe it: 2 nights ago it was clear skies!! But of course with the moon almost full high in the sky.
So finally started with an object that's been on my list: the Heart Nebula IC 1805. Nice FOV with my 2032mm focal length.
It's a work in progress because this is the combined data of a bit over 4.5 hours and I want to have at least 10 hours for SHO and HOO.

I used the Optolong L-eXtreme for the Ha and OII data and also tried the Optolong SII 6.5nm filter but the moon was just to much.
So this image is around 75% of Ha and OIII data en 25% of SII data. Made my own version of narrowband processing with it

Bortle 6/7
Meade LX200 8" f/10 ACF OTA
Ioptron CEM25EC mount (no guiding)
Optolong L-eXtreme filter
Optolong SII 6,5nm filter
Zwo ASI071MC Pro camera

Captured with SharpCap Pro / White balance R50 B50
L-eXtreme: 18 x 600 sec / Gain 90 / Offset 4
SII filter: 10 x 600 sec / Gain 90 / Offset 4
20 x darks. And 50x flats + 50x darkflats per filter

Stacked and separated the Ha and OII and the SII (as Ha) with Siril

SiriL and Photoshop
Siril: Crop, Histogram Transformation
Photoshop: integrated the channels, Levels, Camera Raw Filter (blacks, clarity, contrast, color, noise reduction)

Hi Menno, Lots of nice detail in that - well done for getting out any sort of image this month. Just cloudy murk here.

The colours you have look like Hubble palette ? Now of course I'm intrigued how you did it without using 3 separate filters?

I'm guessing that you took the L -extreme data which would have given you reddish Ha nebula with bluish OIII in the surrounds and shifted the spectrum in some way so that red was shifted towards green ...and then merged in SII data all mapped to red?

SII and HA capture always seem pretty immune to the effects of the moon unless it is really close by the object of interest (which it wouldn't have been) but - in my hands - O3 detection suffers under bright skies.


Anyway it's interesting and looks good

Tim

Thanks Tim!

Indeed lucky. Here too clouds are ruling And indeed 1 clear night in a month.
And yes, the colors are somewhat Hubble Palette like and indeed done with a color camera.

The SII filter is new and I am using it as extra data. So I'm experimenting with it now. I can only use the red channel of it, the green and blue are useless. Even the flats only work for red
What I did was that I stacked it in SiriL and that has a default script in it to stack Ha and OII data and saves it as grayscale. This I used for the L-eXtreme data were, as per usual, Ha is Red and OIII is Blue.
It also has a script to extract only Ha and that I used for the SII and that becomes Green.

In Photoshop I then made 2 images.
One in HOO, so in a new empty image Ha in the Red channel and OII in both the Green and Blue channel. And did then some tweaking.
The other one I did in the Hubble Palette, so SHO. I place SII, Ha and OII in the RGB channels and I then used this manual to get the Hubble Palette colors.
But I didn't have enough SII data, it was way too noisy. So I ended up with using the HOO as layer on the SHO and used opacity so that only a bit of SHO was bleeding through
SHO does already work, see the small example below, but like I said: too little data for that. I think that here in the city, the SII only really works without the moon.

Menno

Thanks Menno. That makes a lot of sense. Given that it easy to separate out the O3 and HA channels then I see that one advantage of the L extreme with an OSC is that you collect both channels at the same time - saving time and using dark sky time more efficiently.

best wishes

Tim

Having more than enough time here to play with data due to the ever lasting autumn here. Seems winter just gives its time to autumn with months long cloud cover

Collected more SII data last year of Melotte 15 and here some results.
The SHO version in Hubble Palette is now way more defined.
And the second one is my own adaptation of SHS. That gave an interesting effect but the red and blue of SII was giving it a very "restless" affect. So I processed it the same as the Hubble Palette and reduced the blue which is now just showing a hint of blue.
So it's more a "artistic freedom" processing instead of scientifically processing

Hi Menno,

Your Hubble palette image now much improved and better defined! Good job. Doing similar things here and concentrating on narrowband - in between dashing out to throw a plastic sheet over everything as the next rain shower blows over. Appreciate the dramatic artistry of the last picture but prefer the more scientifically comprehensible SHO version - with SII looking as if it is better defining the ionization edges and that nice blue OIII at the core.

Tim