First Nebula Image with OSC camera

[Mr Green]

Hi All,

It's been 3 weeks with literally no clear skies where I am which is depressing although used the time to read up and practice on image processing therefore time hasn't been completely wasted. 

While I still have tilt issues after spending roughly 8 hours over 3 separate nights at the beginning of the month messing around with the tilt plate on my camera, I've now acquired the SkyWatcher Flattener/Reducer made specifically for the 72ED therefore hoping this will provide an improvement over the StellaMira Flattener I have been using.

I'm also in the process of adding Astrodymium Rotating Tilt Adjusters via Flo that I hope will be easier to use than the tilt plate on the 2600mc pro.

while Ive been practicing image processing, ive been really wanting to have a crack at hubble palette and was wondering the best way to achieve this.

I have the Optolong L-Pro & L-extreme filters and was wondering if it was worth getting the below Sii filter.

https://www.firstlightoptics.com/optolong-filters/optolong-65nm-sii-narrowband-deep-sky-imaging-filter.html

My thinking is to use the subs from the L-extreme in red & green channels and Sii in the blue channel when processing via photoshop but wanted to know if this would be worth while or not.

Perhaps the L-pro could work and save me some money?

any feedback would be much appreciated as always.

Jon

[Elp]

Lpro won't work as it's a LP broadband filter, if anything it might skew any broadband colour as last time I tried it it had a green tint to the image.

I'm sure there's a script workflow you could use which converts the RGB into SHO but I don't use scripts, obviously the image would be devoid of any specific S2 details.

Askar have recently released their NB colourmagic filters specific for this job with osc cameras, I'm sure other manufacturers have been making the same dual band filters prior to Askar.

[Mr Green]

I've not been able to get my head around scripts (via siril) so thought my best bet was to use 3 separate images in photoshop for each colour channel.

I almost went for the Askar colourmagic filter but went with the L-extreme instead which is frustrating.

Is the Sii filter I highlighted not worth it?

[WolfieGlos]

Using Siril’s scripts is quite easy.

Take all your light frames, and put them into a folder called lights. Repeat for biases, darks and flats (use those folder names), and then use the script called OSC Preprocessing. Done 🙂 Just make sure the 4 folders are all in the same directory and that Siril is pointing to it. 

For narrowband, if using the lextreme, you can do the same as above but use the OSC Extract Ha and OII script. This will produce two files; one for Ha and one for OIII. You can then, in Siril, use RGB Compositing and assign Ha to R, and OIII to G and B for a HOO image. That’s it, aside from then processing the result.

I did manage to find a “cheat” way of getting SII from my lenhance filter, but it’s not technically correct. Here’s a result I got on the heart and soul. I used this guide, it took a few goes but got it in the end, using the luminance noted in the post halfway down with the Eagle Nebula.

I don’t know if you can use an SII filter with OSC though? I’d be interested in hearing if you can, but like Elp said, Askar have just released dual Ha/OIII and SII/OIII so that might be the best option, and that would also double your OIII integration which I understand is usually the weaker signal.

Edited December 31, 2023 by WolfieGlos

[Mr Green]

I think the reason why I struggled with scripts was that I don't take bias frames with the 2600mc pro, I've read in a few places that at most, you only really need flats & darks.

Siril seems to demand bias frames for the scripts to work and the other scripts that I found online that can be manually added to siril also require bias frames.

The askar Oii/Sii is a good shout but if the optolong sii 6.5nb would do just as gooda job, it'd save me a fair chunk of cash to go towards something else.

Will see if anyone has used this filter and can confirm I guess.

[WolfieGlos]

52 minutes ago, Mr Green said:

I think the reason why I struggled with scripts was that I don't take bias frames with the 2600mc pro, I've read in a few places that at most, you only really need flats & darks.

Siril seems to demand bias frames for the scripts to work and the other scripts that I found online that can be manually added to siril also require bias frames.

The askar Oii/Sii is a good shout but if the optolong sii 6.5nb would do just as gooda job, it'd save me a fair chunk of cash to go towards something else.

Will see if anyone has used this filter and can confirm I guess.

I don’t actually know the difference between them, but although it says bias frames, it also works for dark flats which are similar (which you just have to put in the biases folder). You will need either biases or dark flats for flats to work. Dark flats are different to darks though, so not sure if you have the dark flats or not? 

[Mr Green]

Flats definitely work without bias or dark flats for me with regards to removing dust spots and vignetting...

Maybe I'll try my next target with dark flats as suggested and have another crack at using scripts in siril.

Still want to know people's thoughts on whether the sii optolong filter is worth using with the l-extreme....

[alacant]

On 31/12/2023 at 23:04, Mr Green said:

you only really need flats & darks.

 

 

Edited January 6 by alacant

[Mr Green]

Happy New Year and thanks for the reply to my thread.

Keeping it simple is definitely what I've been doing so far with regards to registration and stacking. 

I've used Deepsky stacker for all of my images so far and have only used Siril for initial stretching, background extraction & minor colour calibration before using Photoshop.

Moving forward, I planned on processing stacked images entirely in Photoshop.

Blue channel always seems to be the noisiest therefore thought that using a stacked image with the Sii filter might create a better final image along with the ability to pull out more colours.

Maybe I'm trying to run before I can walk, just wanted to know if my idea had any logic to it I guess.

[Mr Green]

Going back to my question with regards to achieving hubble palette with the Optolong L-extreme, I'm now tempted by the below instead of the Optolong Sii 6.5nm as I'll also get more Oiii data.

https://www.firstlightoptics.com/askar-filters/askar-2-colour-magic-c2-duo-band-siioiii-filter.html

Any thoughts are welcome.

[Elp]

Should work, bear in mind the S2 signal you're capturing is a quarter compared to if you were imaging in mono as it'll only be picked up by the red pixels (OSC is usually an RGGB pixel matrix), but the boost in getting O3 twice (as per your choice of filters) will help, o3 is usually the noisiest too. Note depending on target S2 can sometimes be a weak signal (more often than you may think).

Edited January 1 by Elp

[WolfieGlos]

On 01/01/2024 at 14:07, Mr Green said:

Going back to my question with regards to achieving hubble palette with the Optolong L-extreme, I'm now tempted by the below instead of the Optolong Sii 6.5nm as I'll also get more Oiii data.

https://www.firstlightoptics.com/askar-filters/askar-2-colour-magic-c2-duo-band-siioiii-filter.html

Any thoughts are welcome.

If I wasn't planning to go to mono later this year then I would be picking one up. I see no reason why it shouldn't work.

[Mr Green]

Had some clear sky last night for the first time in a month and this is what I got.

Tried hubble palette but struggled and this is the result.

Struggled to fix the gradient but relatively pleased.

[Elp]

It's a good result. If you open the image in Siril and do a green noise removal you might find it gives you more of that Hubble pallet yellow/blue look. PI will also do it.

Maybe just check your r, g, b histogram peaks are also in alignment, a colour correction routine will do similar.

Edited January 6 by Elp

[Swillis]

On 31/12/2023 at 22:04, Mr Green said:

Siril seems to demand bias frames for the scripts to wor

You can edit the script files so it doesn't need the biases.

I did a similar thing for processing DSLR data without darks. From what I remember you need to remove the section where it reads in the files your not using and then you also need to remove any reference to using the bias value.

 

[Mr Green]

I'll have another image to process tomorrow hopefully as currently imaging the Tadpole Nebula although a little on the small side.

Definitely not a bad shout to run the images through Siril for green noise reduction.

[Mr Green]

1 hour ago, Swillis said:

You can edit the script files so it doesn't need the biases.

 

I've messed about trying to edit scripts in Siril and didn't have much luck.

I'll no doubt have another crack at it though. 

[WolfieGlos]

Why not keep the green in the image and use it for your profile pic? Mr Green? Geddit? 🫣

Anyway, nice result. Which filters did you use? Did you get a SII or duo SII/OIII filter? 

Edited January 6 by WolfieGlos

[alacant]

15 hours ago, Mr Green said:

this is the result

Lovely image. Even in the jpg, there's loadsa detail. Without the green...

[ollypenrice]

33 minutes ago, alacant said:

Lovely image. Even in the jpg, there's loadsa detail. Without the green...

I'm never comfortable with very green NB palettes and find that much more appealing.

Olly

[Mr Green]

13 hours ago, WolfieGlos said:

Why not keep the green in the image and use it for your profile pic? Mr Green? Geddit? 🫣

Anyway, nice result. Which filters did you use? Did you get a SII or duo SII/OIII filter? 

Not a bad idea!! I just used the L-extreme filter for this image.

I'll get an Sii/Oii filter at some point soon and hopefully have better results.

[Mr Green]

1 hour ago, alacant said:

Thanks for doing this with my data, this looks great!! 

[Mr Green]

Evening All,

In a bad habit of sharing my images on this thread, if there's somewhere else I should be doing it, please feel free to give me a telling off and direction as to where I should do it. (Perhaps there's a thread for beginners to post on).

I managed a couple of hours on Bodes Galaxy after a failed attempt on the Witch Head which I think is a no go from my bortle 7 garden.

I struggled with this one mainly because I had an awful gradient that I think I tackled pretty well.

Hope someone appreciates the image and as always, I'm open to constructive criticism 🙂