#1  
Old 11-05-2015, 06:57 AM
LewisM's Avatar
LewisM
Novichok test rabbit

LewisM is offline
 
Join Date: Aug 2012
Location: Somewhere in the cosmos...
Posts: 10,388
I must be missing something...

I accidentally dida ful run of H-a last night, WITH the LP filter in place.

When I apply the H-a in the correct way to the LRGB (to make an Ha-L(RHa)B), I get cyan stars caused by the LP filter in the H-a subs. I have desaturated the HaR in PS, I have removed the blue channel from the HaR combined image before applying, I have left it 100% mono, but I still get cyan in the stars. Nothing seems to cure it, and balancing the resultant after to remove the blue also makes it look wrong.

Any ideas, BESIDES reshooting all the Ha subs again WITHOUT the LP filter
Reply With Quote
  #2  
Old 11-05-2015, 07:06 AM
rally
Registered User

rally is offline
 
Join Date: Sep 2007
Location: Australia
Posts: 896
Check your stellar profiles in each channel and see if they are the same
My bet is they are not the same size.
Reply With Quote
  #3  
Old 11-05-2015, 11:41 AM
jase (Jason)
Registered User

jase is offline
 
Join Date: Sep 2006
Location: Melbourne, Victoria
Posts: 3,916
Create an RGB master (no Ha blend). Stretch with levels and curves but focus on stars, not the extended object. You want the extended object to remain dim but stars bright. Boost their colour and profile using levels, curves, saturation. Shadow/Highlights can do this in one step very well, but only tweak shadows. Layer this RGB master over the top of the HaRGB blend as lighten mode. You now have the best of both worlds, natural looking stars with uber details from your HaRGB combination.

There are multiple ways to doing it.
Reply With Quote
  #4  
Old 11-05-2015, 03:25 PM
LewisM's Avatar
LewisM
Novichok test rabbit

LewisM is offline
 
Join Date: Aug 2012
Location: Somewhere in the cosmos...
Posts: 10,388
That is how i corrected it thanks Jase. Now if only i had remembered to lock focus before going to bed... not much shift but enough. 5 hrs data down the drain...
Reply With Quote
  #5  
Old 11-05-2015, 04:26 PM
Slawomir's Avatar
Slawomir (Suavi)
Registered User

Slawomir is offline
 
Join Date: Sep 2014
Location: North Queensland
Posts: 3,240
Don't worry Lewis about your lost 5 hrs,

Assuming you will utilise 30 nights a year and 6 hours per night, multiplied by say 60 years of astrophotographing that gives us 10800 hours of collecting sky data...
Reply With Quote
  #6  
Old 11-05-2015, 05:42 PM
alpal's Avatar
alpal
Registered User

alpal is offline
 
Join Date: Jan 2012
Location: Melbourne
Posts: 3,602
I always shoot with the 2" CLS-CCD filter installed regardless of filter used.
I don't see how it would make any difference with an Ha filter.

cheers
Allan
Reply With Quote
  #7  
Old 11-05-2015, 07:30 PM
LewisM's Avatar
LewisM
Novichok test rabbit

LewisM is offline
 
Join Date: Aug 2012
Location: Somewhere in the cosmos...
Posts: 10,388
I assume it is the LP filter - I recall when using an FLI OSC that every frame would come out blue before I neutralised the background in CCDStack.

I can't see what else it COULD be. Never had the issue when NOT using the LP filter with the Ha as I usually do.
Reply With Quote
  #8  
Old 13-05-2015, 07:17 AM
gregbradley's Avatar
gregbradley
Registered User

gregbradley is offline
 
Join Date: Feb 2006
Location: Sydney
Posts: 17,877
Quote:
Originally Posted by Slawomir View Post
Don't worry Lewis about your lost 5 hrs,

Assuming you will utilise 30 nights a year and 6 hours per night, multiplied by say 60 years of astrophotographing that gives us 10800 hours of collecting sky data...

Subtract 50% for equipment niggles, 25% for not being able to image because of work, 25% for bad weather and 25% for being in the middle of upgrading your equipment and waiting for adapters etc that mean you spend 2,200 hours in the negative for no images!!!

Greg.
Reply With Quote
  #9  
Old 13-05-2015, 06:20 PM
AlexN's Avatar
AlexN
Tunnel Vision

AlexN is offline
 
Join Date: Mar 2008
Location: Caboolture, Australia
Posts: 6,801
^^ that post is gold, hillarious and hideously truthful all at the same time.
Reply With Quote
  #10  
Old 13-05-2015, 06:33 PM
LewisM's Avatar
LewisM
Novichok test rabbit

LewisM is offline
 
Join Date: Aug 2012
Location: Somewhere in the cosmos...
Posts: 10,388
Truth is often times worse than fiction. What a shocker 2014 was!
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 06:51 AM.

Powered by vBulletin Version 3.8.7 | Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Advertisement
Bintel
Advertisement
Testar
Advertisement