#1  
Old 27-02-2021, 04:44 PM
TrevorW
Registered User

TrevorW is offline
 
Join Date: Aug 2006
Location: Western Australia
Posts: 7,300
Soemthing to comment On

Critique, constructive criticism welcome no BS
Attached Thumbnails
Click for full-size image (carina 8 minutes10s lights and darksV1a.jpg)
220.7 KB59 views
Reply With Quote
  #2  
Old 27-02-2021, 05:02 PM
Karlz's Avatar
Karlz (Karl)
Registered User

Karlz is offline
 
Join Date: Jan 2021
Location: Lake Macquarie
Posts: 142
How many and how long are the subs you took? Which scope? Processing software?
Reply With Quote
  #3  
Old 27-02-2021, 05:05 PM
Startrek (Martin)
Registered User

Startrek is offline
 
Join Date: Dec 2017
Location: Sydney
Posts: 3,333
Hi Trevor,
Iíll be the first one but I need a little more info please
Nice Carina
Scope ?
Mount ?
Camera type DSLR , cooled ,uncooled ?
Exposures ?
Darks ?
Flats ?
Filters ?
Guiding ?
Dithering ?
Location ? Without divulging your exact location
Sky conditions Bortle class ?
Moon phase ( assuming it was captured over the last couple of nights , so heaps of moon glare ? )
Stacking program ?
Processing software ?

Cheers
Martin
Reply With Quote
  #4  
Old 27-02-2021, 05:27 PM
AdamJL
Registered User

AdamJL is offline
 
Join Date: Sep 2010
Posts: 408
Hey Trevor. I echo the above comments, but it also looks a little unfocused to me. How did you focus it?
Reply With Quote
  #5  
Old 27-02-2021, 05:47 PM
RyanJones
Registered User

RyanJones is offline
 
Join Date: Jun 2018
Location: Melbourne,Australia
Posts: 1,210
Hi Trevor,

Beautiful star colours. The gray centers to the brighter stars means they’ve been white clipped. This can happen when you stretch the image beyond the dynamic range and then try to pull back on the highlights. The image is also a bit noisy. This can be either stretching feint data too far or that your signal to noise ratio is too low. More subs will help with this or a cooler sensor. As the others have said, you haven’t provided enough information to really pin point where the improvements can be made.

Cheers

Ryan
Reply With Quote
  #6  
Old 27-02-2021, 06:56 PM
Alchemy (Clive)
Quietly watching

Alchemy is offline
 
Join Date: Jul 2007
Location: Yarra Junction
Posts: 2,993
Ok Iím going to assume itís a picture that has 8 minutes 10 secs of data, given the name of the picture.

Astro imaging to be done well needs lots of time, Letís say more than 10 minutes if thatís the case. Even a bright object should be something that has plenty of time on, the longer, better the results. I canít overstate this.

There is detail in the very core, but outside of that itís noisy due to lack of data.

Iím having a guess you have used a star reduction in photoshop the brighter stars close together have bars in between them, I guessing youíve done the magic wand on stars, expand selection, feather, then applied a minimum filter. If itís not that then some attempt at processing the brighter stars has been done.

The image seems to have a blue cast over the darker areas, you can open it and run the cursor over it and in the info tab you will see the RGB values, thereís lots of methods for getting the color balance better, probably a simple suggestion Iíd download an image of this that you think is really well done and see how yours compares in terms of color, sharpness, etc, this is a bright object with lots of different areas, thereís usually an area of blank sky somewhere that you can use to get at least a good idea if youíre in the ballpark color wise.

On a positive your flat field seems ok enough.

My biggest advice is time time time. hours not minutes.
Reply With Quote
  #7  
Old 27-02-2021, 07:13 PM
TrevorW
Registered User

TrevorW is offline
 
Join Date: Aug 2006
Location: Western Australia
Posts: 7,300
Scope -EON110ED at native f/6

Camera -QHY183C no filters
Total Exposure- 8 minutes in 10s subs with darks nothing else stacked DSS processed PS CS2 with Astronomy Tools action Pack

Mount- Losmandy G2 PHD2 guiding
Suburbs Perth about Bortle 5 Moon first quarter
Focus - Bahtinov mask
Reply With Quote
  #8  
Old 27-02-2021, 07:43 PM
RyanJones
Registered User

RyanJones is offline
 
Join Date: Jun 2018
Location: Melbourne,Australia
Posts: 1,210
Quote:
Originally Posted by TrevorW View Post
Scope -EON110ED at native f/6

Camera -QHY183C no filters
Total Exposure- 8 minutes in 10s subs with darks nothing else stacked DSS processed PS CS2 with Astronomy Tools action Pack

Mount- Losmandy G2 PHD2 guiding
Suburbs Perth about Bortle 5 Moon first quarter
Focus - Bahtinov mask
So the first and most key piece of advice is more time...... in an order of magnitude !
Reply With Quote
Reply

Bookmarks

Thread Tools
Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +10. The time is now 10:06 AM.

Powered by vBulletin Version 3.8.7 | Copyright ©2000 - 2021, Jelsoft Enterprises Ltd.
Advertisement
Bintel
Advertisement
NexDome Observatories
Advertisement
Limpet Controller
Advertisement
Testar
Advertisement
Astronomy and Electronics Centre
Advertisement