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View Full Version here: : NGC 3584 and NGC 3603 nebulas


alpal
04-03-2014, 03:20 AM
The area around Eta Carinae has so many jewels that
it's difficult to know what target to pick.
Aren't we lucky in the Southern hemisphere?
I was going to target the Running Chicken nebula but then I realised
I could get both of these nebulas in one frame.

I only managed a puny 55 minutes of integration time
before the clouds came rolling in.
The weather forecast said clear & was wrong once again.
The field was very busy with so many stars & I had to
reduce their brightness or they would have overtaken the nebula.

5 x 5 minutes of Luminance binned 1x1
2x5 minutes each of RGB binned 2x2.

I wonder if this is worth pursuing with more data?
All comments welcome.

Larger size on my flickr photos.

cheers
Allan

alpal
04-03-2014, 11:32 AM
I did a bit of a re-process - a few changes.
I increased the red in LAB colour to bring out the background a bit more.
I also thought I dampened down the stars too much
so I increased their brightness & gave them more colour
from some short 25 second sub frames -
some were at the maximum well depth - but not now.

Also - a better name for this thread would have been
NGC 3576 & 3603 Nebulas but I can't change it now.
There are so many NGC objects in the frame.

Larger size on flickr.

atalas
04-03-2014, 06:41 PM
Nice pic for such low signal mate....I don't agree with an unbalanced color bias though mate,and the gradient needs to be addressed.

alpal
04-03-2014, 08:57 PM
Hi Louie,
I agree - I tried to push low signal data too hard.
The gradient is fixed - I hope?
I completely re-processed it & deleted the old version from flickr.
I attach a small version here & a large version is on flickr.

cheers
Allan

gregbradley
05-03-2014, 01:16 PM
Off to a good start there Allan. It needs more data and the colours need to be balanced as there is a red bias plus excess blue in the background.

How are you combining the Ha? Some make a master luminance with some Ha and Luminance, red and Ha into one red and combine LRGB that way. A bit trial and error with no ability to backtrack and alter.

I personally simply add Ha as a red and a blue layer in lighten mode and adjust with curves to boost or suppress as desired. Usually that protects the RGB stars as they are usually brighter than the Ha red dots.

Greg.

alpal
05-03-2014, 01:30 PM
Thanks Greg,
I thought the last pic I posted was a lot better than the first ones.
I struggled with the processing on this one due to the small amount of data.
I still thought it was worth posting.
Have you seen the larger version on flickr?

There is no Ha in this image unfortunately -
There would have been but the clouds rolled in.
I normally make 2 luminance layers - one for ordinary
Luminance & the other for Ha used as luminance.
I then combine them at approximately 50% each.
Ha should really only be added to Red - but I'm a rebel.
Ha makes stars smaller & makes others disappear.
That makes nebulas look better as the field of stars
can overpower a nebula taking away it's beauty.

cheers
Allan

alpal
11-03-2014, 11:04 AM
I did another slight re-process.
I worked on the gradients to bring up the darker areas.
Notice at the top of the image -
a black dusty area structure has been revealed?
I removed the blue cast in the background.
A larger version is on flickr.

Is this better?