Ngc 253

[Peter Ward]

Gave this one a bit of a dust-off, tidied up the noise a tad,
and upped the image scale from the earlier version, so I guess you'd call my picture of this rarely imaged galaxy a re-pro with extras. :)

A focal reducer was used to deliver a paltry focal length of around 2500mm

The LRGB data was captured at 1:1 binning with 9 micron pixels.... sheer sampling madness, I know, but, someone's got to do it. ;)

The link is here (http://www.atscope.com.au/BRO/gallery386.html)

[blink138]

oh wow nice!
pat

[Andy01]

Bam! Right there is what 2500mm does for galaxies then - :eyepop:
Looks a tad magenta on my screen though.
Amazing detail Peter - it's like you could reach out & touch it .... :thumbsup:

[Peter Ward]

Thanks Pat.



Bam! ?

:question: Yep. I like that :thumbsup:

Sorry, I was using an uncalibrated monitor...colour should be fixed now.

This was also taken about 100m above seal level in the 'burbs of Sydney.

No Chilean mountain dust was disturbed or injured during the image capture process :D

[leon]

Peter we are going to have to shoot you very soon, :D how can one compete, :shrug:that is just awesome, well done just doesn't cover it. :thumbsup:

Leon :thumbsup:

[gregbradley]

Very nice Peter. Uh oh a focal reducer. They can be fun given how much quicker you get the data. Sometimes there can be a cost though.
With a Planewave the cost is no backfocus for any guiding. In your case fatter stars than the original data?

A bit of an issue with star registration or perhaps CA from the reducer?

I never know what to expect on the colour of this one as examples vary wildly. I wonder what the new colour calibration tool in PI would show.

What is impressive still is the detail and what appears to be almost differentiated stars in the outer belts. They almost seem to be resolving into single stars.

Greg.

[Peter Ward]

Well, not sure about the shooting part, but thanks very much Leon. I take it
the image is a keeper :)



Thanks Greg.

The reducer if anything makes the stars a tad tighter, there is absolutely no CA.... but I hear you when to comes to back-focus!

I had to get second cover-plate for the CFW adapted solely for the reducer.

Yes there is some fringing around the stars, but purely due the seeing varying during the exposure sequence.

I guess I could have "fuzzed" it out, but didn't want to lose the snap...or as Andy aptly said "Bam!" in the data

I rather like the structure in faint fuzzies at 2 o'clock. Faint.... but beautifully resolved by this instrument.

[multiweb]

That's awesome Peter. You're raising the bar. :thumbsup:

[gregbradley]

Thanks Greg.

The reducer if anything makes the stars a tad tighter, there is absolutely no CA.... but I hear you when to comes to back-focus!

I had to get second cover-plate for the CFW adapted solely for the reducer.

Yes there is some fringing around the stars, but purely due the seeing varying during the exposure sequence.

I guess I could have "fuzzed" it out, but didn't want to lose the snap...or as Andy aptly said "Bam!" in the data

I rather like the structure in faint fuzzies at 2 o'clock. Faint.... but beautifully resolved by this instrument.[/QUOTE]

You can always do some decon on the subs that are enlarged. That has a certain workability.

I quite liked imaging with the reducer apart from in my case having to slum it and use a guide scope. Something like the outer parts of the Helix in 2x2 binning is about 4 hours worth of exposure. You should have a lot of fun with it as its obviously top of the line optics.

Greg.

[peter_4059]

Peter, what's going on around the outside edges of the galaxy? Maybe it's my cheap monitor but it looks really grainy. There also seems to be a wide blue horizontal line through the right hand side of the image and a remnant of a satellite trail through the left hand bottom section. Perhaps it's just me but it doesn't seem to be as good as what I've seen you produce before?

Nice detail in the galaxy though

Peter

[Peter Ward]

Edge artifacts are probably due the fact I selectively reduced the noise.
There is indeed a satellite trail! ...but I decided it was faint enough on my (calibrated) monitor not to bother with.




Thanks Marc :thumbsup:

[alpal]

Nice & sharp Peter,
The images on this site are just getting better & better
just when we thought that there was no room for improvement.

cheers
Allan

[peter_4059]

[QUOTE=Peter Ward;1335596]Edge artifacts are probably due the fact I selectively reduced the noise.
There is indeed a satellite trail! ...but I decided it was faint enough on my (calibrated) monitor not to bother with.
Yep, calibrated monitors are becoming quite main stream these days. Here's a screen grab from mine. As I said in my original post, it's a nice image but I've seen you do better.

[Atmos]

The fine detail that you've captured is exquisite! Still not sure about the colour but the luminance is excellent.

[multiweb]

Tough crowd :lol:

[Peter Ward]

You think ? :thumbsup:





Well... the satellite trail stays...it can be my version of a watermark :)

As for the colour..I have tweaked it a tad more, but given I image from light-pollution central, I suspect with all the gradient removal required I'm chasing my tail here and am making subjective changes that are probably not valid.

Sigh...Moving to a dark site would make imaging such a breeze...:prey:



Very kind Allan.

[multiweb]

You're only as good as your last gig mate. :lol: Your fault. ;)

[Peter Ward]

Indeed.
The crappy colour registration was bugging me.....Dropped the RGB into PixInsight.

It did a spectacular job of distortion correction. No fringes!

Not sure about the DBE tool...still have some weird localised colour in the background...but the (new! improved!) repro (same URL) does look cleaner.

[h0ughy]

what a fantastic cruddy image ;) !!! whinge, whine and complain I can only hope that one day i get the change to get something like this. Fantastic details and i certainly appreciate the resolution.

[multiweb]

Now that looks like a chart32 shot from an observatory on top of a mountain. Sub zero cool. :thumbsup:

[Peter Ward]

Thanks Guys....nice to be compared with the Chart guys...but I can only get glimmers of their silky smooth, high resolution imagery from my location.

Imaging from the 'burbs I am always up against the LP noise wall and wait for many nights to get one with reasonable seeing.

Try as I might, I could not get Maxim to fully register the RGB frames. Hence I'm rapidly becoming a Pixinsight fanboy.

Their image registration with distortion correction tool is remarkable. ..and well worth discovering if you haven't already done so.

[gregbradley]

That's way better Peter. I'll keep that in mind next time I have an image that is not registering well (it happens).

I found PI fabulous for registering nightscape images that other software could not handle. Its an odd program but some of its tools are just cutting edge.

Greg.

[atalas]

I'm working on this as well Peter,and If I can do half as well as this from our location I'll be happy :)

Excellent work :thumbsup:

[Stevec35]

That's a nice NGC 253 Peter although it looks like you could have used more data because there's a bit of colour noise in the background. I'm constantly surprised at the quality of the images you produce given the considerable light pollution at your location.

Cheers

Steve

[Peter Ward]

Ta Steve...I'm slowly getting a handle on PixInsight's noise and DBE tools, which look very promising for removing the noise I'm always struggling with. As a result I don't think I'm done with this one just yet...plus haven't event begun to explore their sharpening tools.



Much appreciate Louie. One significant upside of using a long FL is it reduces the effect of sky glow..i.e. sky brightness per pixel....which in our neck of the woods is hardly trivial.



Thanks Greg. Yep while the PI interface, as I think Marcus put it: about as much fun as bamboo under the fingernails, it has some simply amazing tools :thumbsup:

[LewisM]

Much better on now my monitor - the previous rendition was decidedly lilac on my CALIBRATED monitor :P

[Peter Ward]

Whew! Order has been restored to the force :)

[LewisM]

Yes sorry I had a little flatulence. The force is restabilised :)

[Slawomir]

Impressive detail Peter, well done :thumbsup:

[marc4darkskies]

Paltry indeed!! Why anyone would want to image this galaxy with anything less than 3130mm is utterly beyond me! :lol: :P At least you used respectably large pixels! ;)

All up though, not bad for a hobbled Alluna! :D :thumbsup: :thumbsup:

[Peter Ward]

Thanks gentelmen. I suspect I might have used the FFC corrector rather than the FFR....too many *TLA's to keep track of :)

*three letter acronyms

[rustigsmed]

Fantastic - love the resolution !
:thumbsup:

[peter_4059]

Have you tried the new PIXINSIGHT photometry-based colour tool? I think it is a new approach to get the initial RGB image properly CALIBRATED. Might help avoid future lilac episodes. :thumbsup:

[Peter Ward]

:thanx: Not yet.
On the "to do" list.
Consider me suitably chastised.

[markas]

Terrific detail,Peter:thumbsup:

Mark

[Paul Haese]

The latest version looks pretty reasonable for an image taken in light polluted skies. It does seem a shame you have not got this scope parked some where dark. Surely you could do an arrangement with itelescopes for hosting and loaning of time.

[Placidus]

The final colour is beautiful, and the crispy crunchy detail is just amazing. Lovely.

[Peter Ward]

Thanks gentlemen. As for moving the ‘scope to a dark site, yes that would be nice, but I like to change out optical configurations and filter sets which is not easy to do remotely. That said, I’ve been looking at the prices of rural plots within a few hours of Sydney...ouch! I suspect I’ll need to win lotto first :)

[cometcatcher]

That's very sharp! At this level, galaxies that otherwise look like stars pop out.

I'm imaging 253 at the moment but it won't look like this unfortunately.

[Martin Pugh]

Hi Peter

late to comment here. Terrific detail in the galaxy indicating good focus.

Needs to be hit with the Tony Hallas Green Pixel Gun (as he calls it in his talks) and there is a very simple way in PS to get rid of satellite trails with two clicks of the mouse :-)

cheers
Martin

[Peter Ward]

:lol:

Thanks Martin...yep...the noise control is hardly sublime....maybe just lime :D

That said I haven’t got a problem with satellite trails...they add a little something IMHO

Pretty happy with the detail....looked at the short FL stuff and am confident I’m doing OK in the resolution stakes :thumbsup: