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AstroViking
18-09-2023, 07:23 PM
Hi all,

I won't bore you with a wall of text this time. Sorry oska, I just don't have it in me at the moment. The thought of going back over the litany of problems I hit is enough to depress me...

So, two sessions from my Bortle 6 backyard here in suburbia.

Equipment:
SW72ED @ 420mm / HEQ5-Pro / ASI183MC-Pro / SV165+SV305 / Kstars/Ekos

Session 1:
* Gain: 100
* Offset: 10
* Temperature: 0 degrees C
* Exposure: 30 seconds
* Frames: 170 Lights, 25 Darks, 34 each of Flats and DarkFlats (85 minutes integration in total)
* Filter: None

Session 2:
* Gain: 100
* Offset: 10
* Temperature: 0 degrees C
* Exposure: 120 seconds
* Frames: 60 Lights, 25 Darks, 50 each of Flats and DarkFlats (120 minutes integration in total)
* Filter: L-Enhance

Data then stacked with Sirilic, dragged into Siril for a quick pre-process and star removal via starnet++ before being poked, prodded and generally messed around with in Affinity Photo.

I think I've resolved the gremlins that plagued me, so let's hope the next clear night is not a night of frustration...

Cheers,
V

Doogs38
23-09-2023, 10:13 AM
As a local famous amateur imager (looking at you John-san, ie. Oska) once said “it wouldn’t be art if you didn't suffer for it” :rofl: Seriously Steve, it’s a great image regardless of the pain to produce it. Both the reflection and emission nebula are well capture and so too is the surrounding gas and dust - the 72ed is a nice scope and I like it’s wide FOV (I have one too). There is some mild CA which I’ve learnt to accept is the norm for a doublet regardless of what glass is used, and I suspect the mild star bloat was from your first session without a filter? I always use at least a UV/IR filter to stop IR-induced star bloat. I just wish UV/IR filters were a little narrower and started around 440-450nm to reduce the bluish CA.

AstroViking
25-09-2023, 07:58 PM
Thanks Alex,

I keep procrastinating about leaving the UV/IR cut filter in the setup, given the small advantage it gives. I think from here on, it can stay in there if I'm not using the L-Enhance.

Cheers,
V.