How do you do Ha pr...
 
Share:

How do you do Ha processing? Do you have any tips?  

  RSS

(@mcbbcn)
White Dwarf Customer
Joined: 1 year ago
Posts: 14
May 14, 2019 01:41  

Hi Everyone,

I'm just getting my toes wet with Ha processing and I have a very shot I took of Crescent nebula with my WO + FR (380mm).  The shot is just 15min. (3 x 5min) from Portland, downtown.

Here is a link to the folder where I have my MF, MB and MD for Ha filter. If you spot anything wrong, please let me know. The flats were created at 22K ADU with my QHY9M CCD camera: https://www.dropbox.com/sh/0zwp2cb252sbyj0/AABidnU2-plcidpb_C2LSnB2a?dl=0

Also, I'm attaching what I see in APP with my integration.  It's just a black background with some white dots (stars).

app ss

I'm assume I don't see any gradients or contrast because I don't have any signal but if you think it's something else, please let me know.  Finding the focusing point with the narrowband HA filter was a pain, but I think I'm focus, although it's hard to tell with narrowband filters.

And last, if you have any tips for Ha processing, please share.  I tried to find a video tutorial on Ha processing but I could not narrow one down.

Best,

Miquel


ReplyQuote
(@rcfmitch)
Red Giant Customer
Joined: 9 months ago
Posts: 57
May 16, 2019 19:44  

I just looked at your single / combines..  300 sec frames .. there is something seriously wrong with the bit dept or Gain values. 

there is just not enough info from you to draw any kind of conclusions.

but your flats look good...

Mitch

 

crescent nebula 300sec 1x1  frame1

 

 

This post was modified 1 month ago by rcfmitch

ReplyQuote
(@mcbbcn)
White Dwarf Customer
Joined: 1 year ago
Posts: 14
May 17, 2019 16:21  

Hi Mitch,

Thanks for your reply.  You are correct about the gain values. I had a friend of mine who’s been doing Ha for years and told me that 3 subs of 5min. each is nowhere close to the amount of time I need to set for my sub-frames to have a signal that lifts from the left side on the histogram. He takes single 20min. subs. So, I will be spending a night at his backyard with my equipment when we have a clear night and do some longer subs and see if I can lift the signal above the black background.

Thanks for your help

Miquel

This post was modified 1 month ago by mcbbcn

ReplyQuote
(@rcfmitch)
Red Giant Customer
Joined: 9 months ago
Posts: 57
May 17, 2019 19:30  

Being its a QHY9 mono , CCD, you need to shoot in the 600/1800 sec subs.

but dont underestimate 120 x 600 sec over 48 x 1800 subs . Something to think about.

its all about SNR. 

Clear steady skies.

Mitch/ (Astrodude. ( youtube)


ReplyQuote
(@mcbbcn)
White Dwarf Customer
Joined: 1 year ago
Posts: 14
May 18, 2019 17:23  

Thanks Mitch, I appreciate it!


rcfmitch liked
ReplyQuote
Share: