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The Pacman. NGC 281 in Ha, OIII and H-beta.

RobH

By RobH
in Imaging - Deep Sky

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RobH

RobH

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Hi folks,

Got the subs for this on Monday night while waiting for the winter stuff to come up. :)

Details are...

WO ZS80FD, Atik 16HR, Astronomik Ha, OIII & h beta 13 nm filters.

LX as guidescope.

L X 18

Hb & OIII 10 each binned 2x2

5 minute subs

Ha used as luminance in 2 separate layers @ 50% opacity with saturation adjustments applied to the RGB layer between the application of the Ha luminance layers. This avoids the 'salmon pink' effect of a 50% or above opacity Ha luminance layer.

Cheers

Rob

10561_normal.jpeg

(click to enlarge)

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RobH

RobH

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Thanks folks :)

The subtle shades of colour are down to the use of the H beta filter for blue...it seems to give some really interesting oranges, and deep oily browns, and isn't too far removed from normal colour, while still keeping many of the advantages of narrowband imaging.

Originally, the starfield somewhat overwhelmed the nebula on this, so I selected pretty well all of the stars, and then applied noise reduction using neatimage to them. This had the effect of sinking them into the background slightly, without obviously blurring them, and the nebula became the thing that drew the eye, rather than the stars.

Cheers

Rob

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RobH

RobH

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Paul, I really like narrowband :)

OK, the exposure times are up, but you have that much more opportunity to image in a lot of ways....the moon isn't too much of a problem, and tonight for example, out back of me there's a bit of haze, which is giving a distinct orange cast as it picks up local sodium glare, but narrowband filters are shooting straight through it :D

I was very tempted to grab some SII data for this, and go for a hubble pallete, but have rotated the camera for the current targets...may well grab it later though.

Cheers

Rob

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RobH

RobH

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Thought some of you may be interested in seeing what the unprocessed Ha stack was like for this one.

Flat and bias calibrated, then just an initial arcsin(arcsin)x stretch in Fits liberator. Nothing else done.

I was pretty pleased when this first appeared on the screen :)

Crystal clear and dead still here last night...fog rolled in at 2am.

Cheers

Rob

10603_normal.jpeg

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MartinB

MartinB

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Great Pacman Rob. I had a bash at Kelling using an ED120 and QSI 532ws. Interesting to compare your HaHaOIIIHb with my HaHaRGB. There are some nice gradations of colour at the edges of the neb in yours which don't turn up in my image although I do like the star colouration that RGB gives. I use a similar technique for blending the Ha to avoid the salmon colour although I think I probably used a slightly lower percentage in the blend that you did. You have retained a bit more of the very faint Ha which I have in the mono but not the final mix.

Here's a link to my effort

http://www.astropixels.co.uk/Pacman%20HaHaRGBhalfsize.jpg

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RobH

RobH

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That's an excellent image Martin...obviously I must have missed it first time around!

The H-Beta does do some very interesting things colour-wise...my N.America and Elephants' trunk images are with the same filter combination, and contain the same variety of reds and browns.

I'm now starting to shoot RGB star subs to use in narrowband images, to try to keep the star colour evident in your pacman. I didn't do that with this one though as I was just shooting it until the HH got to a decent altitude, and this was originally more of a trial run than anything, but I'm very pleased with how it came out.

Cheers

Rob

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Psychobilly

Psychobilly

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Hats off to the narrowband crowd... If we could guarantee more clear nights I might even be tempted to start having a go but with imaging opportunities so rare these days I just got to stick with the grab it while you can OSC approach... the processing would appeal to the latent ---- in me (insert your choice of the G or N word here) as I dont want to offend anyone...

Billy...

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