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petershah
29-11-2013, 01:44 AM
Not done a great deal for a while....the weather in the UK is depressing but I got this one more or less finished .....
I started this one a few nights ago.... this one doesn't get that high in the UK.....I managed 4hours of H-alpha then got to work on some RGB no such luck with the cloud grabbing the odd frame here and there. Last night the clouds parted so I set to work only just managed to get enough, still short of green frames with only one at 840s...I think I compensated pretty well removing gradients as the came up.
Ha=4hours 30min subs Red 2x1200s plus the Ha, Green 1x840s and Blue 5x1060s....even with the odd exposure values it was surprisingly easy to balance.
thanks for looking


http://www.astropix.co.uk/ps/images/a0934.jpg
http://www.astropix.co.uk/ps/images/a0933.jpg

TimberLand
29-11-2013, 03:29 PM
Great effort for the Horse Head from the UK and dealing with clouds. Some nights you just want sucker holes but get 8/8 cloud cover. The atmosphere enables us to survive but sometimes it just plain gets in the way.

I always think of the first images ever of the Orion Neb and think of the gear used to to that in 1882 and how far we have come as amateurs and can bag faint regions of the sky like the HH.

jase
29-11-2013, 03:53 PM
Lovely result Peter. Colours of the scene contrast well. Thanks for sharing.

RickS
29-11-2013, 04:23 PM
Well done, Peter! I'm surprised you managed to get such a good colour image with so little data.

Cheers,
Rick.

petershah
29-11-2013, 11:19 PM
Thanks all....yep the UK isn't a great place for sky time we sometimes have to wait months for a clear night....I'm just glad I have the AG12 it really hoovers up those photons and maximises the available time.

gregbradley
30-11-2013, 09:43 AM
A lovely Horeshead. My only comment is the colour shade of the Ha areas. Its got a touch of the salmon hues. That comes down to your Ha blending method. Ha as luminance = salmon colours so you have to be careful about that. Ha + L as Lum and Ha + R = Red works so does Ha as red in lighten mode and Ha as blue 15% opacity as blue. Adding Ha as a luminance layer is pretty unworkable in my experience. You can get away with a small amount sometimes and it will add a bit of detail but usually at the expense of rich and nice reds and colour in general (blues get damaged as well).

Greg.

strongmanmike
30-11-2013, 09:43 AM
Nice result Peter, I feel for you UKians must be very frustrating at times but then it's all relative...think of the guys who live at high altitude in northern Chile where over 80% of night sky time is useable across the year, sky brightness consistently around 22mag/squ arc sec and steady seeing at median FWHM values of around 0.7 arc sec prevail (meaning that visually through an 8" scope you wouldn't be able to detect any seeing issues at all much of the year - I can't really imagine what that would be like.??) with best values hitting 0.2" :eyepop: compared to them we all live under a bright, regularly cloudy and violently moving soup :sadeyes:

Mike

petershah
30-11-2013, 07:15 PM
Many Thanks everyone... Mike you are not wrong it is very frustrating....what I would do for skies like that

Hello Greg, I know the 'Salmon hues' you talk about very well, however I really cant see them here....at least not on my monitor :confused2:... my processing had many stages and was not as you described, My method is quite unconventional really. I used both Ha+R,G,B, and an RGB and also constructed a luminance layer out of all combined data.
Salmon hues come from an imbalance between the Luminance and RGB and is not a just product of Ha, you can quite easily get them with a none H-alpha Luminance layers too.....