Ngc6888 The Jellyfish Nebula

[Burly]

13.5hrs on the jellyfish nebula, skywatcher 200pds , zwo533mc, L Extreme filter,APT , Siril , processing in Startools, only thing I omitted was deconvolution , I’ve not really got my head around that maybe I should get ivo to take a look for help on better settings and use of this module .

mk4.1 jellyfish.jpeg (354.21 KiB) Viewed 7835 times

[admin]

That's a respectable Jellyfish!

You will definitely want to start using deconvolution, particularly since 1.8 and 1.9 - there's a lot of (real) detail to bring out.

Do let me know how we can help.

[Burly]

Hi Ivo using the deconvoloution module im unsure of best settings to use and sometimes the stars end up a bright dot of light which i dont think looks correct ,if you could look at the data file and suggest a work flow to use in deconvoloution module that would be helpful,and choosing stars to use in sampling or which stars to avoid i usually go for stars with a clear green spot ?,obviously decon is better to use as some detail can be rcovered im assuming .all calibration frames used Darks ,Dark Flats and Flats ,stacked in siril preprocessing script .
https://www.dropbox.com/s/2tc1iipxn1y14 ... s.fit?dl=0

Dave

[Mike in Rancho]

Jellyfish, Cocoon, Crescent...all kind of the same anyway.

That is nicely respectable though for not an easy target. Lots of background Ha, which takes extra integration to get looking decent, and I have had trouble with that OIII encasement. You got good amounts of that all around the whole thing.

SVD should clarify those details quite a bit more. The stars, well, yeah it can depend on your taste for pinpointing and transition. In other threads we've been starting to discuss how much being mindful of saturated cores might affect that.

[decay]

Nice stuff, Dave I had a quick go with your data set:

NewComposite_01.jpg (648.8 KiB) Viewed 7731 times

I pushed back the background in order to bring out the nebula. Not sure about it, what do you think?

SVDecon revealed a lot of detail, I think? There have been not too much usable stars for SVDecon sampling, so I decided to use synthetic model only. But I guess there could be more to optimise. We could try, if you like.

Best regards, Dietmar.

[Burly]

Hi dietmar processing is so subjective nice processing, personally I like to see the background gases if it’s there after slogging 13hrs on a target , the data’s there for anyone to play with feel free I’d love to see what others pull from it , I will definitely have a play about with this data more.

Dave

[Mike in Rancho]

Thanks for letting us try it, Dave.

I actually like Dietmar's presentation, and normally I'd probably lean in that direction myself, maybe with a little more saturation. 13 hours seems like it ought to be plenty, but I guess it all depends on conditions. I captured 3 hours on the Iris last night, and it's looking like maybe I should be looking to get 30 instead. I have a hard time making faint dusty stuff from Bortle 8 look good.

But since you mentioned wanting the background emissions, I tried to stretch and reveal as much as I could. Pretty choppy and grainy though.

The red and blue structure of the target itself is awesome and really showing the 13 hours. With the background bright, there's a lot here, and I had to really downsample (after starting with a 71 bin in ST) a lot in order to get a compressed jpg around 500kb.

Burly Crescent HOO ST9-155 1B.jpg (520.19 KiB) Viewed 7672 times

I did use SVD, but only a couple samples, of which I juggled around too to try to find better stars. I ended up with a few funny ringing shadows, but deringing helped most of it, followed by dering in Shrink module. Star shapes may have been a little off, making this more trouble. Many of them seemed a bit triangular? I went through the same a few months back, and it ended up my mirror clips were probably pinching. I had installed the clips just barely touching, but that was inside at 75 degrees. All good until imaging in the winter at 40 something, creating those triangles.

[Burly]

Nice rendition Mike , nice to see other people’s processing,I’ve been fighting with stars for ages which I put down to my baader mk3 cc and back spacing I may try a https://www.firstlightoptics.com/coma-c ... ector.html
and I’ve just fitted a cnc spider to my 200pds now awaiting clear skies to test and recheck collimation , I have seen some images on Astrobin using the maxfield and if my stars look like that I would be happy, clips have no pressure as three blobs of silicone hold mirror .


Dave

[Mike in Rancho]

Sounds good, Dave. At your f/5 (?), the Baader may not be as much of the well-confirmed trouble it is at f/4, but whether that is just away-from-center star shapes or also includes the center field blur the Mark III imparts, I'm not sure.

I believe the TS is a rebranded Sharpstar and thus identical to my 0.95x. I really like it, especially compared to the Baader, and of course at f/4. I have wondered if they are correct as to the field of correction and if it really covers APS-C. But that may be other issues I have, such as perhaps only a 2 inch focuser, and not getting tilt and backspacing right. There's also a 4-element 1.0x version that is claimed to work for full frame, a little pricier and also a good bit longer body than the 0.95x. Both are of course way longer than the very stubby Baader.

[Burly]

Hi Mike , yes I believe your right about the Ts being a sharp star .

Dave