Hi All,
Long time, no post. Many factors came into play which restricted the amount of free time to pursue imaging, however all was not lost given I put valuable time into finally automating my observatory, thus data acquisition is now fully unattended. I’ve updated the equipment page with a couple pics if you’re interested, nothing exciting. With the freedom to collect data from a dark sky whenever I please (assuming its clear!), I expect I’ll be able to push myself to try a few tedious imaging projects. So to that end, I’d like to present one such initiative which in all honesty, I thought I’d never complete as I really should have started the data acquisition a couple of months earlier.
About the image
The image is a straight RGB composite consisting of three hours data per panel. A synthetic luminance was created to boost S/N in the fainter regions, but for the most part I opted to keep to the conventional RGB data where possible to minimise colour shifts. Panel overlap worked out ok - no requirement to go back to collect more data to fill in the “blanks”…a major relief let me tell you! I did however throw out approximately seven hours of poor data associated with high level clouds or dismal guiding (which I believe I’ve now resolved *sigh*). I utilised TheSky to create a scaffold image in which the panels were registered against prior to stitching to control rotation. The last three images I’ve produced with my gear have been mosaics; this one tallies as the fourth and let me tell you the processing doesn’t appear to be getting any easier. This has certainly been the most technically difficult image I’ve attempted to date. Dealing with neutral sky backgrounds seems to be easier than star clouds of our Milky Way. I actually thought the colour balance was significantly out on the center panels given they’re not the typical golden hues associated with the region. So I recombined the data over a few times, then realised what I originally produced was correct as the small Sagittarius Star cloud is quite a large object spanning 1.5 degrees (the equivalent of three full moons), but is partly obscured by dust, and contains predominately bright B through to F type stars. I was also under the impression that the swan was the same red hue as the eagle…how wrong was I! You learn something every day! Anyway, I do however feel colour fidelity has been lost in some regions due to the strict panel matching process. I’ll work on this technique with time through other projects. My Photoshop proficiency is rusty to say the least. In summary, the synth lum panels were created and stitched matching brightness and contrast between them. I then created the RGB and registered them against the stitched lum to ensure accurate alignment. Stitched the RGB panels matching colour balance and hue. Erased areas of the lum to ensure the straight RGB data filtered through, then flattened lum and RGB layer, then relayered again for colour enhancements. Colour boosting applied using a heavily DDP stretched and saturated RGB layer. Minor noise reduction and colour balance tweaks, seasoned to taste. Processed in MaximDL, CCDStack, Registar and Photoshop CS4. The presented image has been significantly reduced in size to make it web friendly.
Hope you enjoy the swim around this scene. I’ve attached TheSky mosaic plan for your reference. How bizarre, an image of the Eagle nebula, that actually looks like an eagle with its wings spread. Still think the Seagull nebula IC2177 takes the prize however! …and what’s with the giant foot print that has stepped on M8, IC4685 and surrounds all about…
Thanks for checking it out. I’ll now disappear back into the shadows…
I see what you mean re the colour fidelity, it does look a little sorta two tone (??) but the gorgeous grand vista, the sharpness and over all quality more than make up for it
Cheers Humayun. A picture speaks a thousand words eh!
Quote:
Originally Posted by gregbradley
A masterpiece Jase.
Amazing effort and what a result.
Congrats. You can't see any joins. Fantastic.
Greg.
Thanks Greg. Yes, quite some effort. Nothing like challenging yourself now and then. Looking forward to producing a single frame image soon. Should be a walk in the park in comparison. Thanks again.
Quote:
Originally Posted by Ric
Beautiful Jase, an outstanding piece of work.
Cheers Ric. Please you liked it!
Quote:
Originally Posted by renormalised
Just as any great cook will have it...wonderful composition. Another great dish from the "executive chef"
Pleased you enjoyed the culinary delight served Carl. Wouldn't say it was cooked to perfection however. If you like your steak rare, then it may just do. Thanks for the comments.
Quote:
Originally Posted by Benny L
That is something else Jase!!!!! :0
Thanks Benny. Nothing like a little resolution on a widefield image. Its hard to beat a mosaic.
Quote:
Originally Posted by strongmanmike
Rather incredible work Jase .
I see what you mean re the colour fidelity, it does look a little sorta two tone (??) but the gorgeous grand vista, the sharpness and over all quality more than make up for it
Mike
Cheers Mike. Yes, colour fidelity is almost always compromised in some form. Resampling has an impact as well. The full size image I've provided has actually be reduced by 65%! What I noticed is that when the image is resampled/reduced it alters the saturation. On the 1:1 (100%) image, the tonal range looks ok, especially around M8... which on the resampled/reduced image present I think looks too heavily saturated. Will see how it looks on a print sometime. Thanks again.
Quote:
Originally Posted by iceman
Well that's quite incredible!
Amazing image. Not enough superlatives! Speechless!
Thanks Mike. Certainly an interesting area of the sky which took a little planning to get the "ideal" composition. Pleased you liked it.
That is just awesome mate. It's going to take me a while to fully appreciate this. Still sinking in. Since your Rho Oph I'm starting to get into doing mosaics too and learning registar. You're an inspiration mate.
An amazing and welcome return jase.
The high res image is fantastic - each individual object is so well resolved and processed.
Once again...inspirational!
Doug
Well done Jase - Its great t see you are still refining your craft. Never happy with the status quo!
I am pretty much out of the game now. Work, study and family give me little time to take pictures and since I sold the STL, it hasn't been anywhere near as rewarding, even with a 20Da that a friend kindly lent me.
I will probably be selling my gear soon, I'm not using it. I've got more than $10k of stuff but strangely my wife isn't hassling me to sell it, I just think it would be better used to tidy up a few finances. I've always been keen on AP so I will come back to it again later in life when 30Mpx cameras are cheap! Keep an eye out on the classifieds although I don't think there is much you need.
not only is this image an absolute superlative example of what someone who knows what they are doing, can produce.
But it serves as an example for uber noobs like me, to aspire to something greater. Let me put that into perspective, i bought a QHY8 a few days ago, and have felt like throwing it in the bin, this however gives me the incentive to stick at it, and that surely must be a reward in itself.
.
Yes, quite some effort. Nothing like challenging yourself now and then. Looking forward to producing a single frame image soon. Should be a walk in the park in comparison. Thanks again.
Thanks for the comments.
That is just awesome mate. It's going to take me a while to fully appreciate this. Still sinking in. Since your Rho Oph I'm starting to get into doing mosaics too and learning registar. You're an inspiration mate. 
