working on stellar profiles in m17

[Alchemy]

hello all, with the weather the way it is in melbourne its a chance to up the processing skills.... this time its stellar profiles, hopefully this one has the goods. i want to have the stars so you can tell their colour and not just white dots. i found the line tool and ran it over the stars ... very informative, of course it helps if you know what you are doing :shrug: so what ive aimed for is


not burnt out in the middle of the stars,
colour blending to a white point.

trying to tick the other boxes too

ie

non crunchy stars
color balance ok (?) i think so
histogram not clipped , sky value 20-30
detail in the nebulosity

i could have bumped up the saturation but for this experiment not nesccesary i think. note crop is 1:1 so would equate to a 30 inch x 20 inch print section.

so guinea pigs required :D constructive pointing allowed.

clive

[AlexN]

its a stunning image in my view... VERY detailed, the center of the stars do seem nice and not burnt, and also very smooth

[strongmanmike]

You're on a mission huh? ;)

A really excellent image in every respect Clive!

You are really living up to your namesake

Mike

[gregbradley]

It looks very good to me. In fact the whole image is very good.

Greg.

[Phil]

Very nice. The star colour look good to.
Phil

[Dennis]

Hi Clive

They look good to me, although that is somewhat of a gross understatement. Both the detailed crop and full field look quite outstanding.

Cheers

Dennis

[iceman]

That's a beautiful image, Clive. The detail in the nebula is quite striking.

And the star colours! :thumbsup:

[Garyh]

Hi Clive,
Ok my summary.....

non crunchy stars......:thumbsup:
color balance ok (?) i think so.......:thumbsup:
histogram not clipped , sky value 20-30 .......:thumbsup: (I like it about 25-30 myself)
detail in the nebulosity.......:thumbsup: Excellent!

Very nice image in every respect. Nice color balance stars are nice and natural looking and heaps of detail in the neb itself..The detail in the neb its self is really amazing, even the very brightest parts show that lovely mottled texture which you have brought out really well...I think this is when your new camera with its full dynamic range really helps!

More please...:)

[Matty P]

Stunning image Clive, there is absolutely nothing wrong with this image.

So much detail and lovely colour.

Very well done. :thumbsup:

[Alchemy]

yep, if youre going to have a go, gotta get it right.

the feedback that you get is amazing, 2 years ago i didnt know a whole lot about image processing, since then i have learnt a heap..... im just wondering whats next in producing good images.

i am currently thinking about what i will do (this is your fault mike) for the next years...... going to rule out galaxys as a mono chip will just kill for the luminance factor, which leaves nebs and such, i need something to pretty much fill the frame with detail, something not always done (rule out eta or M42,.... m16,17 too small ) ive got 3 ideas which i will work on.... oh and after seeing martins and jases helix shots not doing that either:rofl:



gary i think youre right, they are very different beasts the DSLR and the 16 bit astro cameras... mind you DSLRS do a fantastic job and are now 14 bit and with some clever processing who knows whats possible. its taken a little while to come to grips with the techniques available thaty i never knew existed or at last how to use, so now ive got digital development in the armoury and the line tool is very revealing

im just waiting to see if jase gets out the pixelinterferometer out and puts it under the microscope. if we can get a pass there, maybee we can slip one past the judges next year


thanks everybody for having a look, :thanks:

[Peter Ward]

Indeed Clive....you got it right! Well done.:thumbsup:



But this bit isn't right...a 14 bit D/A does not make a 14 bit sensor...any more than a 16 bit D/A makes a 16 bit sensor...its all about the sensor not the D/A....and in the case of 5 micron pixels (CMOS and CCD) they just don't have the well capacity.

One of those marketing myths that needs to be nipped in the bud ;)

[Alchemy]

i think you're right there, as a 6 min exposure has a bright image with a dslr, yet my qhy8 is pretty dark...... yep clever marketing by the camera people,

[strongmanmike]

As ground breaking and amazingly useful equipment that it is, I wouldn't worry tooooo much about Jase's pixelinterferometer, he ran my CG4 image through that remember..with gastly results buuuuut it still won a Malin and appeared on NASA's APOD :P.

Just be careful, there is more to producing a great astronomical image than just the quest for UCPP...it might "seem" necessary because you percieve that everyone else is doing it buuuuuut....;)

You can do it Rocky!!! I can feeeeel it Aaaaaadriaaan!!!!

Mike
ps. UCPP = "Unecessarily Convoluted Perfect Processing" :whistle:

[AlexN]

lol...

[jase]

Sorry to disappoint Clive, but I've got no constructive comments on these fantastic images. You've done some good research on stellar profiles and how to manage them;)...and it shows. The use of the line tool in such a manner is simply the beginning to diagnosing image quality and problems. Drag it across the image to check for gradients that arent easily detectable. The area tool is great to determine colour shifts in backgrounds so you can neutralise sky colours as required. Learning the tools and when to use them is the key.

As for whether you've hit the mark for a comp. Hmmm not sure. Mike is right. You need to pull off something rather special, unique and push the boundaries. The pixelinterferometer is broken, besides what would I know anyway?:lol: Martin summarised it perfectly in his recent APOD post;

"Those guys at APOD do choose in some strange ways....for example, I regard my best image to date as the 5 panel mosaic of Corona Australis ....which took 3 months to image, is around 40 hours exposure, and something like 180 individual frames.....APOD not interested. Shoot a 90 second RGB of an eclipsed moon, take 5 minute to process it...send it in along with millions of others who must have photographed it, and you get an APOD?!"

The same can be said for astro comps...do the judges truly recognise the effort one has gone to in producing such a spectacular image? Rarely. Its the finished product that is judged, not the journey or "saga" in getting there. Sure its great to get some recognition (Malin, APOD, whatever) as it can be quite a motivation to get out there and work harder towards perfection, but don't lose focus in that the only person you are trying to impress is yourself. If you're constantly suprising yourself with your imaging output, you're on the right path. Each image should invoke new developments and thoughts on how to do things better.

Look forward to seeing more. An FLI vs QHY shootout could be on the cards. After all, its not what you have, its how you use it.

[Peter Ward]

"I see your Schwartz is as big as mine.....let's see how well you handle it"

(from Spaceballs)

[Alchemy]

i am so far

as for the competition i dont expect to win anything,( and having seen yours, mikes and martins efforts it will be a little while before i catch up:whistle: but watch out im not standing still) but it is a great motivation to try and do better and push the boundarys as far as i can.


true mike its about being different, i used to do a lot of landscape photography, and most people would shoot the 12 apostles on the great ocean road from the point that said shoot here, if you want a great shot climb down to the beach and shoot it with a perspective no-one normally sees.


cheers clive

[multiweb]

Very cool nice shot Clive. :thumbsup: I love M17. Such a cool object to image. How did you tone down the middle? Mine looks burnt out in the center although I captured much less details.