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troypiggo
11-05-2012, 11:32 AM
My first Hubble Palette image. I redid data from Wednesday night to include NGC6144/5 this time by rotating 90 degrees. Much happier with this composition. Pretty happy with the blue outer shell coming out around 6144/5

I was too tired to do flats last night, so this isn't flat calibrated yet. That's obvious looking at the right hand side blue channel. Will do them tonight and post an update when ready. Edit - flats now applied in the "final" version right.

Fully processed in PixInsight - dark, flat and bias calibration, integrations, "RGB" combination, and some stretching. No sharpening etc.

Also posted a mosaic of the corners and middle to look at the star profiles. Think they're not too bad?

Image overall looks pretty green to me. Haven't tinkered with the channel weights at all, so not surprisingly the Ha in green channel is pretty dominant. Once I get the flats in there, might tinker a bit more with the colours.

Edit - bit more processing done on the final image. Figured out a way of using PI's STF sliders to adjust the channel balance of the RGB combined image to take a bit of the green out. To my eye, this looks a little less overbearing, although still dominant as it should be. What do you think?

1600px version of the final image here (http://www.flickr.com/photos/troypiggo/7178519884/sizes/o/in/photostream/)

Whatchya reckon? Any advice on the colour balance of these NB images greatly appreciated.

peter_4059
11-05-2012, 12:24 PM
Awesome Troy. You must be happy with your gear now. Bit green though ;)

troypiggo
11-05-2012, 02:15 PM
Thanks mate. Very happy with how things are going at the moment. Now I just need to step up and be able to use it!

PS - can I borrow your Gradient Exterminator to get rid of that green? :P

ozstronomer
11-05-2012, 05:00 PM
Well done mate, that flattener seems to spot on now.

I agree a bit of Gradient Exterminator will be the ticket.

Stevec35
11-05-2012, 05:05 PM
Yep - looks good. Once you lessen the green I think you'll have a real keeper.

Cheers

Steve

Mighty_oz
11-05-2012, 05:33 PM
Nice, thanks for the colour :) Will look even better when u adjust those channels to let out the other 2 colours. Have a look at Mike's S he's done almost the same colouring as u have.

bmitchell82
11-05-2012, 05:37 PM
Nice work troy, possibly you can do some selective layer contrasting, to bring out the details that you want and give it almost a 3d feel. :) Im not going to say the other one as its been said a fair few times already :) Look forward to the repro

BM

RickS
11-05-2012, 05:42 PM
That's an interesting look, Troy! DBE in PixInsight is a great tool for dealing with gradients. It's not simple to use, so check the Harry's Astroshed tutorial first. Also try SCNR if you want to remove green.

Cheers,
Rick.

bmitchell82
11-05-2012, 06:09 PM
HLVG plug in for Photoshop is a saviour sometimes! (can only be used with 32bit )

RobF
11-05-2012, 07:38 PM
Nice work Troy. Look forward to seeing the final version too.

astronobob
11-05-2012, 07:41 PM
Coool target for the hubble Palette caper thing : )
Also interesting to see when them calibrated flats are applied and tinkered more with ? ? All out of my League Troy, But a mighty fine lookin result from here so far !

troypiggo
12-05-2012, 07:21 AM
Thanks again guys. I've just posted "final" version. Really happy with the way it's turned out, but please don't be discouraged from offering advice/critique - I need it.

BTW, for the PixInsight users, here's a quick rundown of what I did:

- Batch preprocessing script for image calibration and alignment, image integration was linear fit
- LRGB combination process with L unchecked, R=SII, G=Ha, B=OIII
- STF auto with the channels unlinked. I find this gives the quickest and closest view before non-linear stretching of what the final will look like after stretching.
- DBE. Very simple as I'm no expert in it. Just generated the sample as default and applied subtraction correction.
- This is the part I think was pretty cool. I did an auto STF again with channels unlinked because of the DBE. Then I zoomed in to tweak the mid-tone slider of the R and B channels to get the colour balance I liked. Then you drag the little blue process icon from the STF to the HistogramTransformation's bottom bar. What this does is copy the STF setting to the HistoTransf to apply. Then just apply the HistoTransf to the image. You'll probably need to reset the STF now.
- Created a lightness mask and applied subtle noise reduction using GreyCStoration
- Very light morphtransform (erosion) to control the stars and found it also boosted the overall image.

That's about it I think. No deconvolutions, sharpening etc.

RobF
12-05-2012, 12:22 PM
Thanks for posting the PI info Troy. There are so many ways to attack NB, and none of them very intuitive. The STF/HT idea sounds VERY powerful. Must give it a spin. Glad to hear the TMB is powering along too.

Fingers crossed for weather for a few days now!

multiweb
12-05-2012, 06:20 PM
Not too keen on the colors but it's a gorgeous field right down to the corners. Well done. :thumbsup: