M20 "Sidonio'd"

[RobF]

I've never been happy with the way my Triffid turned out from Qld Astrofest. I think I've learned a few more processing tricks along the way since then, so what better way to spend a rainy relaxed XMAS/Boxing Day weekend!

I rightly copped criticism for oversharpening the first time, but I guess I was excited there was something there to sharpen....:lol:
Tried to work on the nebula but keep the stars soft this time around.
(Hmm - maybe I should have nuked the stars altogether - they seem to be out of fashion at the moment! ;))

All 3 images 14x5 mins ISO 400, 450D + MPCC on the 8 inch Newt.
1. Original effort
2. Repro (err Sidonio)
3. Cropped repro

Thanks for looking.

[telemarker]

You've nicely controlled the background stars and also retained their colour fidelity. The repro is a vast improvement, gives greater emphasis to the nebulosity. My preference is the uncropped version, love the star cluster to the right, it seems to add to the image :thumbsup:

[jjjnettie]

Nuke those stars Rob. Go on, I dare you.
Your repro is a vast improvement on your first one. It pays to keep good data. Ones skills improve with each image you process, you've come ahead in leaps and bounds.
I love this image.

[strongmanmike]

Wow the overall look has certainly improved Rob with great colour now and at this image size the resolution looks pretty good too but me thinks it wouldn't stand up to any real enlargement though...?

Nice improvement though

Mike

[RobF]

Thanks Keith - I couldn't decide if M21 helped or detracted from the image, so thought I'd have a bit both ways.



Ahahh!!! The power to blink stars out of existence! I'm too tired to try right now though must confess. Maybe another day. Loved your starless M42 though Jeanette.



Thanks Mike. I'm a lot happier I've done about the best I can with the data (for now.... :whistle:).
You're right about resolution - with my rig I get about 1 arc"/pixel, but that slight crop is already pushing things a bit far really. You certainly don't every get to "swim around" in the hi-res versions of my shots. Oh well - at least I'll have plenty of room to grow (when I win the lotto....)

[bmitchell82]

Well im going to go against the grain of everybody else. I actually like both renditions for different reasons, your stars in the first one seem to pop a bit nicer after all this area is very dense with stars. and i like the nebulosity in the second rendiition. Have you tried combining the two? aka layer mask hide all then use a brush to selectively brush in the nebulosity? that way you get the tight crisp stars your looking for coupled with the smooth soft nebulosity. and if some of the bigger stars start to blow out use the same method for them.! a bit of deconvolution and enlargement of the native image size sometihng like 1.5x to 2x though iterations though photoshop and youll have yourself a nice image... that will stand up to large format printing.

just my 2c worth :):thumbsup:

[RobF]

Hmm - I certainly did use layers a lot throughout the reprocessing Brendan, but I didn't combine the original final image at any point - I went right back to the beginning 2nd time around. I might give that a try.

I'm intruiged by what you suggest with PS though and don't really understand. You would resize, then deconv. I'd need a 3rd party plugin for deconvolution though I expect?

Interested in any thoughts on getting better scale out of my images - have assumed up to now its just noise, limitations of GSO optics and tracking errors (usually around 1 arcsec with peaks up to 2" at times) + seeing of course.

[telecasterguru]

Rob,

I think both images have merit and its good to see you moving forward with your processing skills.

Frank

[Prickly]

Hi Rob,

Very nice image. Stars look very nice and the nebulosity looks more detailed I think / apparent over a wider field.

What are the key steps to Sidonio'ing an image? From the looks it this may involve masking I imagine. Seems like this is becoming quite popular. Cant argue with the outcome - looks great.

Cheers
David

[bmitchell82]

well generally you can enlarge the image and work with it at a larger size, ever noticed when you shrink a image down it always looks nice and sharp. so if you go to Image-->Image size and then increase it by say 5% at a time you will end up enlarging the image significantly working at this resolution will allow you to shrink it back to a A3 / A2 size. my images are generally shrunk 20-30% to fit onto a A3 print

If you want to try out deconvolution you can try it out with ccd stack, it has quite a good deconvolution program in it.

do a heavy deconvolution ~150 and a lighter one ~50 iterations, then selectively mask them in. youll have some really good results utilizing this method.

[RobF]

Thanks Frank - improving my processing was a 2009 New Year's resolution, so I'm pleased I'm getting somewhere. Not pretending there isn't always stacks more to learn though - just one more aspect of this hobby that just keeps continuing to offer more challenges!



Cheers David. I was trying to focus on bringing out my softness and detail, which involves different processing approaches. I used layers and selections a lot to tease out detail and stretch the nebula without changing the stars too much. The only point I used layers was to bring through stronger sharpening of the dust clouds in the heart of the triffid itself. Plenty of tweaking of curves, levels, saturation etc. One of the luxuries of having reasonable data to play with is that you can avoid using noise tools that always cost a bit of detail.

I guess the key points for any Sidonio are:
- you spend lots of time trying new things
- you have lots of fun doing so
- you hopefully end up with something you like even more than the original! :lol: ;)

If I've missed something important, I expect the big man himself will fill it in.
Seriously though, I found Jerry Lodriguss' CD book "A Guide to Astrophotography with Digital SLR CAmeras" a huge help in the early days, and there are stacks of threads here about great reference books (none of which I've found time or money to get hold of yet mind you)



Thanks for that detail Brendan. I'd heard you can now download CCDStack, so I'll have to try it out and see how I go. I think I may have tried an earlier version a long time ago and couldn't get it to work on DSLR images, but will try as you suggest. The resizing advice is something I'll certainly have to explore too - most of my playing has been for screen output, so I've never explored the possibilities re resizing and effect on noise and artifacts.

[AlexN]

Rob, I agree with brendan, I think both images have good and bad points.. I think in the original, the blue reflection neb shows through really well, where it seems a little subdued in the repro. The background stars in the first image are a little over stretched and colourless, and again, a little too subdued in the repro.. I think the background milky way in images of M8 and M20 are fantastic backdrops to very pretty targets, and every effort should be made to maintain them, whilst making sure they do not take center stage... Its a balancing act, processing nebulae nestled into the milky way, but they are indeed stunning targets!

Keep at it Rob.. I too have been working on a repro of my last M8/M20 effort... I think its just about cooked.. :) I'll post it shortly.

[RobF]

Hmmm - the other issue is I enjoyed see dark dust lanes through the stars in the original image, but they haven't come through in the repro. Its so easy to get caught up in hours of tweaking to what you think is "perfection", only to realise its way off the mark the next day! That's what's so good about IIS feedback though - you can rely on other people's eyes to help sort you out.

I'll look forward to new M8/20 masterpieces too young Jedi!

Cheers Alex :)

[troypiggo]

Very nice repro. As other mentioned, both orig and repro appeal in different ways. Really like the way you've brought out the nebulosity in the second go.

[Hagar]

Well Rob, I like the repro, The only thing missing is stars! for me you have gone a little to far on the minimum filter or the star reduction but overall a very nice crisp image with great colour without the harsh sharpening of the first one.

[RobF]

Thanks Troy! :) Learning more about processing and PS is like exploring a black hole. If I get time I think I'll have to buy something like "Photoshop Astronomy".



Cheers Doug. The more I look at it the more I have to admit I got a bit carried away dimming all those lovely Duckadang stars. Its just so damned easy throwing out the baby with the bathwater sometimes doing these things.

Makes me take my hat off to the pros that make it look so easy! ;)

[strongmanmike]

Nup, that just about covers it Rob :thumbsup:

[AlexN]

You know what else is fun? Using your USB leads as skipping ropes... Thats my new "its raining" hobby.. Skipping..

So what big whoop wanna fight about it?!!??! :P