NGC6888 Bicolour NB

peter_4059 (Peter) · #1 06-11-2015, 06:00 PM

I'm still trying to process this year's Astrofest data and I've been leaving the difficult ones till last. I've had at least three attempts at this one and finally went back to PS today to allow some easier masking to get the job done.

This is 44 x 5min Ha and OIII taken with my SN10 on the EQ6 with a QSI683 and my first serious attempt at a bicolour NB image.

Here's the full res version: http://astrob.in/224669/0/

As always advice gratefully received.

Thanks for looking.

gregbradley · #2 06-11-2015, 07:53 PM

I'm totally jealous you can capture this object from your latitude. It looks very good. I would up the red though as Ricks image is about as good as they get and it shows more Ha.

Greg.

peter_4059 (Peter) · #3 06-11-2015, 08:16 PM

Thanks Greg. I was never going to match Rick's 28 hours data from Nevada where the Crescent transits close to overhead compared to my 4 hours from Duckadang where it peaks at 25 degrees above horizon but it is a very photogenic target.

RickS (Rick) · #4 06-11-2015, 08:50 PM

I think you've done very well, Peter, with an object at such an unfriendly declination. Nice details and subtle colours... which I appreciate but can't do myself

Cheers,
Rick.

peter_4059 (Peter) · #5 06-11-2015, 09:35 PM

Thanks Rick. I'm looking forward to the next PI workshop so I can work out how to do this without dodgy masking.

RickS (Rick) · #6 06-11-2015, 10:20 PM

Peter,

We've overgrown our space at work and will be moving to a new building before end of year. The new place should have some nice big meeting rooms with projectors for weekend PixInsight workshops

Cheers,
Rick.

RobF (Rob) · #7 06-11-2015, 11:25 PM

OOooooo.......meeting rooms....

And great image too Peter. Must confess didn't realise this sucker got high enough to set sights on. Well done. NB processing still does my head in. Maybe I should try a few Crownies beforehand next time

peter_4059 (Peter) · #8 07-11-2015, 12:01 PM

Cheers Rob. It was just clearing my dunny tent from memory. I've found the bi-colour NB quite tricky to get reasonable neb colours while maintinaing stars that don't look too weird. That's one good thing about PS - you can create cusom masks a lot easier than PI.

RickS (Rick) · #9 07-11-2015, 12:12 PM

Quote:

Originally Posted by peter_4059

That's one good thing about PS - you can create cusom masks a lot easier than PI.

What sort of masks, Peter? I make some fairly complex masks with PixelMath. PM is a doddle if you've done any programming but it's not really any harder than working with formulae in a spreadsheet.

Cheers,
Rick.

batema (Mark) · #10 08-11-2015, 12:37 AM

Again great image. You must be loving the new scope.

Mark

Paul Haese · #11 08-11-2015, 01:58 AM

I feel similarly to Greg. It's nice to see this object being imaged from Australia. Nice detail in the object. Colour palette looks good too.

troypiggo (Troy) · #12 08-11-2015, 07:48 AM

The OIII shell really adds to it, hey. Kudos from such a challenging latitude.

ozstronomer (Geoff) · #13 08-11-2015, 09:24 AM

Nice one Peter, I like your blending of the NB data

Geoff

peter_4059 (Peter) · #14 08-11-2015, 11:29 AM

Quote:

Originally Posted by RickS

What sort of masks, Peter? I make some fairly complex masks with PixelMath. PM is a doddle if you've done any programming but it's not really any harder than working with formulae in a spreadsheet.

Cheers,
Rick.

Rick, I've found trying to create a mask that reveals the nebulosity but conceals the stars is quite difficult in PI. I know you demonstrated this in the last workshop but there are a number of steps involved and I've found it tricky to know if the mask is going to be effective until you try it. I really need to find a pixelmath help file - some of the expressions mean nothing to me $T/3?

Quote:

Originally Posted by batema

Again great image. You must be loving the new scope.

Mark

Thanks Mark. I do like it, it solved the primary mirror dew problem I had with the Newt at every previous Astrofest and the f4 optics really does collect data noticeably faster than the f5 of my Newt. Only problem is it is very difficult to collimate.

Quote:

Originally Posted by Paul Haese

I feel similarly to Greg. It's nice to see this object being imaged from Australia. Nice detail in the object. Colour palette looks good too.

Cheers Paul.

Quote:

Originally Posted by troypiggo

The OIII shell really adds to it, hey. Kudos from such a challenging latitude.

Thanks Troy.

Quote:

Originally Posted by ozstronomer

Nice one Peter, I like your blending of the NB data

Geoff

Thanks Geoff. I've been using Ken Crawfords Colour Mapping and clipping masks in PS and this gives you great control of how the Ha and OIII gets mapped to the colour palette.

RickS (Rick) · #15 08-11-2015, 01:55 PM

Quote:

Originally Posted by peter_4059

Rick, I've found trying to create a mask that reveals the nebulosity but conceals the stars is quite difficult in PI. I know you demonstrated this in the last workshop but there are a number of steps involved and I've found it tricky to know if the mask is going to be effective until you try it. I really need to find a pixelmath help file - some of the expressions mean nothing to me $T/3?

Gerald Wechselberger has some good videos on PixelMath.

http://www.werbeagentur.org/oldwexi/...ixInsight.html

Cheers,
Rick.