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MrB
31-05-2014, 05:53 AM
I've been playing around with NB filters with DSLR's and having lots of fun.

This is 217 mins of Ha, and 90 mins of OIII with a Canon 60Da.
Ha mapped to the red channel, OIII to blue and green.
No darks or flats used.

Processed in AstroArt, but me skills have let me down again, tho I'm pretty happy for only 70mm of achromat :)

I'm still having issues with the flattener, I added a 3mm spacer but this seems to have made zero improvement.... need to sort this, it's getting frustrating.
Image cropped to rid the worst of the coma.

Very small version attached here (damn 200k limit) but a large version(2000x1386) with warts and all is at Astrobin:
http://www.astrobin.com/full/98888/0/?real=&mod=

multiweb
31-05-2014, 09:30 AM
Superb rendition of an old favorite. :thumbsup:

cometcatcher
31-05-2014, 06:59 PM
That worked out very well.

MrB
31-05-2014, 07:37 PM
Cheers guys, its a nice bright easy target for testing.
Will get some more data as I'm sorting the flattener spacing issue, but then it's time to target something more obscure and interesting.

I do enjoy the fact I get 3 times the data with the OIII filter than I do with the Ha for any given exposure :thumbsup:

LightningNZ
31-05-2014, 08:31 PM
Very pretty. I really like the nicely handled stars.
-Cam

Regulus
31-05-2014, 08:45 PM
Nice treatment of one of my favourite nebulas Simon. Well done.

MrB
31-05-2014, 09:24 PM
Thanks Cam and Trevor.

Cam, I can't take any credit for any processing of the stars, that's as they came out of the camera!
'Processing' consisted of stretching, then a single point curve adjust, then the tiniest amount of sharpening was used.
I wish I had the skills to do more but even after watching tutorials I can't get anything to work unless I use the data used in those tutorials!

MrB
01-06-2014, 04:15 AM
A small repro.
I stumbled across Richard Crisp's website and his page about Synthetic RGB.
In the original image above the data in the Green and Blue channels is identical (Both 100% OIII)
With the synthetic RGB image below, I have added 15% Ha data to the OIII data in the blue channel, this is supposed to emulate the Hydrogen beta emission of the nebula and better emulate a true RGB image.
I have however apparently slightly increased noise, decreased detail and blown the stars out a tad in my processing somehow.

More information at Richard Crisp's page, http://www.narrowbandimaging.com/synthetic_rgb_page.htm
and this at Starizona's page: http://starizona.com/acb/ccd/software/ps_morenarrow.aspx

From the Starizona page:
"The effect of having H-beta in an image is to tone down the pure red color of the H-alpha emission (which is the dominant emission in most nebulas), turning it into the familiar pinkish or magenta hue of nebulas in RGB pictures."

Not sure which I like better.