Orpington Astronomical Society

Astronomy => Astrophotography => Topic started by: Carole on Nov 12, 2018, 23:37:22

Title: NGC6820 better processing
Post by: Carole on Nov 12, 2018, 23:37:22
I am going back to a number of my images and reprocessing them, as I wasn't happy the first time around.
Much happier with this result.

This is the original post:
http://forum.orpington-astronomy.org.uk/index.php?topic=11501.0

Original info:
Dual Rig

Atik314L/WOZS71
Atik460EX/ED80
Both with x0.8 focal reducer
HEQ5
Ha 29 x 600 = 4 hours 50mins
Oiii 17 x 600 binned + 5 x 300 = 3 hours 15 mins

Total imaging time = 8 hours 5mins

Oiii taken with Atik460/ED80 and Ha taken from both cameras.
There is some blue signal in there, but it seems to be swamped by the stronger Ha signal

Better view on Astrobin:
https://www.astrobin.com/full/370867/C/?nc=user

(https://cdn.astrobin.com/thumbs/_2jZY67sg7OH_1824x0_ceyYapI3.jpg)

Title: Re: NGC6820 better processing
Post by: ApophisAstros on Nov 13, 2018, 10:48:57
Cant wait for my HA filter to arrive to get some of that lovely fine detail, great image.
Roger
Title: Re: NGC6820 better processing
Post by: Carole on Nov 13, 2018, 11:59:42
Thanks Roger.  Yes the Ha filter will open up new opportunities for you, and of course it will be great at keeping the LP out from your home location.

Carole
Title: Re: NGC6820 better processing
Post by: Roberto on Nov 13, 2018, 13:07:14
Very nice Carole!  HaOIII works really well on these targets. Yellow stars keep their colours.
Roberto
Title: Re: NGC6820 better processing
Post by: Carole on Nov 13, 2018, 18:34:37
Thanks Roberto.

Carole
Title: Re: NGC6820 better processing
Post by: The Thing on Nov 14, 2018, 08:01:28
Nice Carole. It's surprising what you can get out of an image by processing it slightly differently to what you initially thought was the 'right' way. I think a reprocess is always a good idea, the difficult bit is deciding when you have it 'just so' and post it, because really one always has another go and produce a better version after the post. C'est la vie.

Duncan
Title: Re: NGC6820 better processing
Post by: Carole on Nov 14, 2018, 09:52:50
Thanks Duncan.  Once upon a time reprocesses used to be frowned on on this forum, but I am glad that doesn't seem to be the case of late and I could never understand the objection because as you say you can get a completely different result second time around.

I think on some of the dimmer images I have probably just processed them a bit too hard and by "pulling back" a bit I can get a less noisy and smoother result.

Quotethe difficult bit is deciding when you have it 'just so' and post it
Very true.

I think also some of the images I have been posting of late are less usual ones (mainly because I have run out of targets), and I think the reason they are less usual is because they are dimmer and more of a challenge. 

But in the end I didn't want to leave the original process as the only one I posted.  so thanks for your comments.

Must try to do better first time around in future.

Carole
Title: Re: NGC6820 better processing
Post by: MarkS on Nov 14, 2018, 23:47:23
That's made a big difference!

Ignore the detractors - reprocessing is always worthwhile.

Mark
Title: Re: NGC6820 better processing
Post by: Carole on Nov 15, 2018, 08:26:04
Thank you Mark.

QuoteIgnore the detractors - reprocessing is always worthwhile.
Thank you for that too and I agree. 

Caole
Title: Re: NGC6820 better processing
Post by: Fay on Nov 15, 2018, 21:15:49
I must do a reprocess as have a trial PIXinsight for a month