Capture:
Taken at Qld Astrofest 30 June to 5 Aug 2016
Objects in image:
NGC7599, NGC7531, NGC7590, NGC7582, NGC7552, Abell 1111, and 800+ PGC galaxies
Scope: AP140EDF/reducer = 771mm FL
Mount: AP900
Camera: U16M
Filters: Astrodon E series Gen 2 LRGB, 3nm Astrodon Ha, 3nm Astrodon Oiii
Guiding: Lodestar / Borg 50mm guide scope
Image scale: 2.41 arcsec/pixel (drizzled to 2x then reduced to 75%)
Exposures: 36x600s L, 14x900s R, 12x900s G, 12x900s B (15.5 hours)
Processing: PixInsight 1.8
The attached image is a small crop as it is difficult to reduce this to a 200Kb jpeg. Higher res larger crop on Astrobin: http://www.astrobin.com/full/260775/B/ It's worth zooming around the full res version.
Hope you enjoy the image and I always appreciate constructive criticism
Hi Rick,
That's majestic! Well done.
How small we are....
Can I ask what you do exactly with the drizzling of data such as this.
Thanks, Tim. We are small indeed!
When significantly undersampled, I use drizzle integration to increase the resolution, usually by a factor of two, and then downsample when I finish processing if the data doesn't quite hold up at full res. With the AP140 set up at 2.4 arcsec/pixel I'm invariably undersampled even in terrible seeing. This time I doubled the res and then did a final resample at 75% to give a 50% resolution increase over the original data.
Hope that answers your question?
Quote:
Originally Posted by atalas
That's a great short Rickthat galaxy lower left,is that tidal tales showing?
Thanks, Louie. I thought that was a reflection initially but it has a PGC number so I think it's yet another galaxy. There are supposed to be some faint tidal tails between members of the quartet and I was hoping to capture them but I can't see them even with averted imagination
There are supposed to be some faint tidal tails between members of the quartet and I was hoping to capture them but I can't see them even with averted imagination
Bah! easy for me, clear as day those tidal streams
Another great wide field galaxy shot Rick, always fun to peruse such fields looking at all the cool bits and this field has sooo many galaxies, well done
Yeah I ask dude because I would of thought It to be quite difficult at this scale....I never look at maths behind these things...just easier to ask....too lazy.
Erm...the background just looks a little too black...
Just kidding...looks stunning Rick
You could be right, Dunk. I'm never quite sure if I've gone too far either way... at least until a few days later when I'm sure I got it wrong
Quote:
Originally Posted by strongmanmike
Bah! easy for me, clear as day those tidal streams
Another great wide field galaxy shot Rick, always fun to peruse such fields looking at all the cool bits and this field has sooo many galaxies, well done
Ta, Mike. Your rendition from ages ago (2009?) was a bit of an inspiration for me and still looks damn fine
Quote:
Originally Posted by atalas
Hi Rick
Yeah I ask dude because I would of thought It to be quite difficult at this scale....I never look at maths behind these things...just easier to ask....too lazy.
With this fairly fast combination of scope and camera I thought I'd have a good chance of pulling out any faint detail like that, Louie, but I got a bunch of IFN (which I didn't try to push this time around) and no tidal tails. I've not seen any images that show them so maybe they are really faint or maybe even nonexistent
Quote:
Originally Posted by topheart
I was more asking about the steps in PI within the Star Alignment module.....Does the final re-sample equate to the "drop shrink"??
I used DrizzleIntegration with a Scale of 2 and adjusted Drop Shrink to taste (the default of 0.9 was good this time.) That gave me double res data (8192x8192 pixels) which I processed to completion. Then I used the Resample process at 75% to downsample the final image.
The detail in all of those galaxies is extraordinary! You mentioned you were a bit worried about the colour version not being as well as the straight luminance, nothing to worry about there!
Such a rich field, Rick. Running out of superlatives. Beautiful colour and contrast - a jewel-box of galaxies.
Thanks, M&T!
Quote:
Originally Posted by RobF
You got me runnin' goin' out of my mind Rick!
Top shot. Wonderful view of this cluster.
Ta, Rob
Quote:
Originally Posted by Atmos
The detail in all of those galaxies is extraordinary! You mentioned you were a bit worried about the colour version not being as well as the straight luminance, nothing to worry about there!
Thanks, Colin. I'm pretty happy with the end result but it took some work to get there. Just occasionally an image comes together really quickly and easily but this wasn't one of those