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sjastro
08-02-2013, 11:32 AM
I haven't seen too many images of this object in Ha.

2 hr exposure using a 5nm bandpass Ha filter, BRC-250 scope and ST-X10ME CCD.

I much rather prefer monochrome Ha images hence a colour image is unlikely.:)

Larger image can be found here.
http://members.iinet.net.au/~sjastro/ngc2467Ha.html

Clear skies

Steven

allan gould
08-02-2013, 01:41 PM
Superb Ha image - it really looks three dimensional and I agree with your monochrome opinion.

alistairsam
08-02-2013, 02:48 PM
Hi Steven,

That looks really cool

But I do find it odd that there are a number of stars that seem aligned in a 70 deg angle in the whole image. not sure if you've noticed it or am I missing something? looks like the scope sort of jumped, but then you'd notice that in the image although the focus looks soft. Interesting object though.

Cheers

gregbradley
08-02-2013, 05:03 PM
Wow, a 2 hour exposure. That must be some sort of record. With BRC and ST10 it must be really dim.

Nice result. I agree, Ha usually goes south when added to colour images.

Greg.

Ross G
08-02-2013, 10:39 PM
A beautiful b&w photo Steven.

Amazing detail.

Ross.

sjastro
09-02-2013, 09:21 AM
Thanks Greg. In fact NGC 2467 is reasonably bright object.



Thanks Ross.



Not sure what you're seeing here Alistairsam. Could be a registration issue of images. I did restack them and found no difference.



Thanks Alan.
I find Ha images lose the contrast impact when colour is added.

Clear skies

Steven

Larryp
09-02-2013, 03:46 PM
Superb image, Steven!

multiweb
09-02-2013, 05:21 PM
Very cool pic. :thumbsup: That's the snoopy nebula if you rotate it 90 degrees clockwise.

seeker372011
09-02-2013, 09:00 PM
That's a simply awesome image

I had a go at this object some years back

http://www.flickr.com/photos/91784720@N00/4291894987/in/photostream

And your image shows an incredible amount of additional nebulosity and so much sharper

The new gold standard for others to emulate

Narayan

seeker372011
09-02-2013, 09:07 PM
I also agree that H alpha in mono chrome has its own unique charm..think Ansel Adams in space...and the wonderful work of John Gleason

marc4darkskies
10-02-2013, 08:12 AM
Very nice Steve - an interesting , somewhat off the beaten, track object. I'd do some more stretching though - there's definitely more data in there waiting to be noticed.


:eyepop::sadeyes::help::confused2: Ouch! You're hurting my ears Steve!!! :shrug::confuse2: ........ :D

Seriously though, notwithstanding aesthetic and personal taste arguments, far from reducing contrast, adding Ha to LRGB should always mean you're adding information and depth to a colour image that would otherwise not be visible.

sjastro
10-02-2013, 10:29 AM
Thanks Larry.



You have an active imagination Marc.
I thought it was Darth Vadar hanging upside down.:)



Thanks Narayan. Your fine image shows the extensive nature of the nebula.



Marcus,

The trouble with adding RGB colour to a Ha image is that the process itself is inherently contrast reducing. The blending of the R channel into a Ha image to preserve colour balance reduces contrast as the R data lacks the contrast of the Ha data.
No argument about adding information but how many individuals after taking multi hour exposures of say the HH nebula in Ha are a little disappointed once the colour is added.:shrug:

Clear skies

Steven

sjastro
10-02-2013, 10:33 AM
Marcus was quite right in suggesting that more info could be extracted.

Here it is in higher resolution
http://members.iinet.net.au/~sjastro/ngc2467Ha.html

Clear skies

Steven

marc4darkskies
10-02-2013, 11:12 AM
Your contrast comes from the Luminance layer(s) (Ha or LHa blend). The chrominance layer(s) of an image, however balanced or blended, have no bearing on luminance contrast in the final image. It's possible that people perceive contrast better when it's white/grey as opposed to red though and, all things being equal (incl processing techniques), this is what might contribute most to one's personal taste. Let's agree to differ! :)

sjastro
10-02-2013, 04:08 PM
The contrast reduction is due to blending the R-channel of your combined RGB data into the Ha luminance.
The resultant HaR luminance has less contrast then a straight Ha luminance.

Regards

Steven

marc4darkskies
10-02-2013, 10:41 PM
You obviously do Ha blends differently to me. My HaR (Ha blended into R) adds only Ha signal to the chrominance layer (which only contribnutes colour to the final image). All of my contrast comes from my LHa (Luminance as lighten on top of Ha) layer.