I have hit the wall. I have no idea where to go from here with processing. Attached is an image of NGC253 taken with a QHY8 and a Vixen VC200L fully auto guided with a Tak FS102 and a QHY5 guide camera.
The image is a compilation of 13 X 10 minute subs plus 10 X 15 minute subs plus 1 X 30 minute sub. The image was stacked in IP3 and manipulated in Photoshop. No calibration files were taken.
I expected more from this image as the 30 minute image on it's own was near as good as this complete image. All the subs were or at least appeared to be good images with little noise and good data.
Can someone please comment on what would improve this 5 hrs of data.
I have added the reprocessed version. Stars were brought back to colour and some colour balance issues addressed.
Last edited by Hagar; 23-09-2008 at 01:54 PM.
Reason: Reprocessed image added
Your kidding Doug, what is wrong with that, I wish mine turned out as good as that well done i reckon.
And by the way Doug I was not aware that one could combine images of different exposures in Image Plus, I see you have IP3, would this be the reason as I just have IP2 at the moment.
Your kidding Doug, what is wrong with that, I wish mine turned out as good as that well done i reckon.
And by the way Doug I was not aware that one could combine images of different exposures in Image Plus, I see you have IP3, would this be the reason as I just have IP2 at the moment.
Leon
Leon I manually grade the individual files then just complete a TSR Align and then combine the aligned images. I just thought that was the way to do it. This data was taken over a couple of nights and then just combined and played with. Auto grading would exclude a lot of files from the stack so I manually grade the processed files. Easy.
Thanks for your comments. I just had expected more fine detail but didn't get it. Maybe something to do with pixel size or focus or something else. I don't know. It was a lot of data which seemed pretty good at the first viewing of it.
Mate that's awesome. As good as it gets. What don't you like about it? Maybe you've reached the limits of your optics. More details means more aperture? Your guiding's spot on and your focus too... so ... that's it. Ask santa claus for an RCOS?
I might suggest that perhaps in PS, consider:
a very gentle "apply image" using the gaussian blurred version of the image selecting "subtract and an offset between 12 and 45 to remove a light gradient.
Then a layer of Hipass filter to enhance the contrast within the nebula and a hint of unsharp mask and touch of saturation?
The colour balance seems a little off - a tad yellow/green, and the star colours seem to be missing, but otherwise it's a damn fine image.
It's a terrific image Doug but I agree with Mike, the levels just need a little adjustment.
I've had a go, if you don't mind, at getting some more detail out and adjusting the histogram to balance it a little.
It's a bit hard working from the web version but just wanted to show you what I did, the core is slightly blown though but the dust lanes came out.
Just use the saturation sliders to bring back the colour balance, did a slight noise reduction and final sharpen.
I see images like this and I actually feel a little giggle inside. It's just so beautiful.
I don't have any experience whatsoever with the technicalities of shooting or processing -- having discovered the night sky less than a year ago, I'm lucky to get my mount level.
But I know what I find beautiful. And this is just plain beautiful.
Although in some fairness, the reprocess did enhance the dust lane detail and really the overall detail. Wish I understood what Frank (spearo) was suggesting.
I had this object on my next list but weather has not been good for quite awhile so Im glad someone has been able to do it .. and in fine style
Thanks everyone. I had got myself to a point where whatever I did seemed to degrade the image and have tried a lot of diferent things believe me. Time to sit back take it slowly and try to follow some of your advice. It is very easy to look at an image yourself and think that that is as good as it is going to be but a forum such as this gives the originator a chance to firstly learn from other peoples thoughts and expectations and to also learn some new techniques.
Thanks again I will keep trying. PS Andrew I think your reprosess is a vast improvement on mine.
I have spent hours on this one.
Reprocessed using a star mask to allow me to clean up and resaturate the stars. Then the Galaxy was reprocessed on it's own.
I am a little surprised at the diference between monitors, in particular the laptop I do all my work on and the LCD at work. The colour diference is quite dramatic. The laptop is regularly calibrated using Spyder2 Monitor calibrator and does show up most images very well and is a good starting point for professional studio print calibration.
It is evident that each and every monitor has it's own colour cast and brightness base making it very dificult to be truely critical of any image. I am even doubting my own images and calibration. Where to from here? God alone knows because I sure as hell don't.
This reprosses appears to be some improvement but shows I have a long way to go. The first post in the thread now has both images attached.
Doug, I'm in the same boat as you. I collected hours worth of data on 253 in every which way I could and can not get a good result from it at all. I spent days plugging away at PS while I was on crutches, with nothing else to do. I put it down to light pollution corrupting the data and will try again this week-end at Barrambah under dark sky. Your images are far cleaner than any of mine.
Why no flats or darks?
Calibration makes a huge difference to the final result.
The colour balance seems a little off - a tad yellow/green, and the star colours seem to be missing, but otherwise it's a damn fine image.
Agreed flats are worth while (Doug himself taught me that ) however with the QHY8 darks are really quite unnecessary... I've seen the single 30min sub that Doug used in this data, and on its own its one of the best 253 images I've seen... little to no noise, hot pixels etc..
) however with the QHY8 darks are really quite unnecessary... I've seen the single 30min sub that Doug used in this data, and on its own its one of the best 253 images I've seen... little to no noise, hot pixels etc..
