IC 443 The Jellyfish Nebula (now at 10 hrs!)

[TakMan]

Been adding to, as and when, along with other targets as they move into view...

Hope in the next week or so to put the Ha part to bed (as the moon moves out of the way) - would like to perhaps get another 3 hours on it and then start the OIII before the season is out.

Slow going with these crusty old CCDs !  😉

30x 1200 seconds, Chroma 50mm unmounted 3nm Ha, dark and flat frame calibrated + dark flats (aligned/stacked in APP). FSQ106ED @ f/5 - Atik 16200M (running at -20ºC), Atik OAG/SBIG-ST-i

Processed solely in Ps (no Topaz) and stand-a-lone StarNet++ on OSX.

Damian

Do the clicky thing for the full size jpeg (slight crop after stacking)

Using Brendan's (Kinch) super shot as my reference point (although he has the better camera, and scope.... and skies 😀 ), see:

https://www.kinchastro.com/jellyfish-nebula.html

...and I see Brendan has recently jumped to CMOS - the traitor ! 👹

 

Edited January 18, 2022 by TakMan

[gorann]

I think the details in your Ha image are superb Damian! This is the start of a great image!

Edited January 19, 2022 by gorann

[TakMan]

7 hours ago, gorann said:

I think the details in your Ha image are superb Damian! This is the start of a great image!

Cheers Gorann

Although by the time I’ve finished this image (if ever), you’ll have probably mapped the entire Northern Hemisphere!

You are also partly responsible for my other ongoing target - Sh2-223 / 224. Again I could do with a few more hours capture on the Ha before processing - I’ll link your image in when I do!

Thanks again…

D

[scotty38]

Nice images and once I get my quirks sorted I'm going to put some effort in to getting this one done properly (well as properly as I am able)....

[Daniel Karl]

Nice detail - distortion is clearly not something that keeps you up at night (although I suppose the distortion free Tak still keeps you up at night - haha)

I just ordered a new flattener, so I suppose I'll be entertained with shimming to find the right backfocus for the rest of the year and then trying to get the
tilt sorted and the objective properly aligned ... maybe I should start saving for a Tak instead

[TakMan]

9 minutes ago, Daniel Karl said:

distortion is clearly not something that keeps you up at night

You'd be wrong.... there is distortion... tilt (?), upper left is the most obvious!

I'm not sure if it's the focuser, the adapters, the OAG or the camera....

I've tried screwing everything down with the scope at a vertical (to get gravity to help), the focuser is racked most of the way in....

But you know, life is too short and the nights too scarce to worry too much - so it's (or will have to be), good enough !

Some distortion will get cropped naturally from the stacking, some more cropping I can live with.... I'll do my best to process and when I view from a sensible distance, and even on the iPad, it's not too bad -  just !

Would be great if it was 'perfect' , but hey-ho!

Damian

[gorann]

I would not worry the slightest by that little distortion. A 5 min fix in processing if you are up to it (like me). Pixel peeping is in any case for us the imagers and processors (since we have to be exposed to it) and the audience could, would or should not care.

[Daniel Karl]

1 hour ago, TakMan said:

You'd be wrong.... there is distortion... tilt (?), upper left is the most obvious!

I'm not sure if it's the focuser, the adapters, the OAG or the camera....

I've tried screwing everything down with the scope at a vertical (to get gravity to help), the focuser is racked most of the way in....

But you know, life is too short and the nights too scarce to worry too much - so it's (or will have to be), good enough !

Some distortion will get cropped naturally from the stacking, some more cropping I can live with.... I'll do my best to process and when I view from a sensible distance, and even on the iPad, it's not too bad -  just !

Would be great if it was 'perfect' , but hey-ho!

Damian

My focuser doesn't even have threads, so the heavy camera with reducer and filter wheel just hangs off the 2" tube (which probably tilts as well under the load) ... and the tube is about 7cm out to get in focus. I also don't know if the focuser is square to the tube and I bought the
refractor second hand, so who knows if the objective still sits square to the tube (I hope the elements are still aligned - 😄) I don't own a barlow or even a decent eyepiece and it's been 20 years since my last star test ... so at the moment my standards are:
If I go full screen on my monitor and I can't see the distortion without squinting, I'm okay with it. It's a decent 32" 4K IPS monitor, so I'm still quite a bit away from that - hehe. But my eyesight is getting worse, so the problem might sort itself out over time ...