Three Images in one night!

[strongmanmike]

How to satisfy imaging withdrawals :lol:

No imaging for some 6 weeks now (still in the middle of a mega data project that will now probably have to wait until next year to finish :sadeyes:).

Apart from a 3/4 moon, the seeing last night was in a word..?.. terrible but it was clear and although the moon was up..meah, I persevered :stupid:

The seeing was about average at the start of the evening so I quickly grabbed some SII to complete an image of The Ghost of Jupiter that I had started waaay back in March, luckily the seeing for the Ha and OIII back then was really pretty good (seeing is everything) so some rather fine details in this very tiny object (only 40"dia!) are evident even with just the 1120mm FL of the F3.8 AG12, after all it's only the same size as Jupiter on the sky :thumbsup:

Ghost of Jupiter (http://www.pbase.com/strongmanmike2002/image/154904467/original)

After that however.... the seeing rapidly deteriorated :doh:

Soooo not to let a clear night go and given the withdrawals that are annoying my wife by now :P ...I thought meeeah I'll shoot somthing bright - the Jewel Box :2thumbs:

The Jewel Box (http://www.pbase.com/strongmanmike2002/image/156000018/original)

And here is a 100% crop close up (http://www.pbase.com/strongmanmike2002/image/156026124/original) of the cluster

Theeeen the seeing became atrocious with a quick eye scan of the sky showing madly twinkling stars...but it was still clear and still air and cold and I am mad....so what the hell, I pointed the rig at The Trifid and proceeded to grab some data (imaging addict :screwy:) - the subs looked pretty sad and even after some processing magic unfortunately it shows in the final product :doh: heck by the time I was collecting the blue data in the west the stars were like marshmallows and my guiding was commensurately rather erratic :mad2:...yes I could have used some decon but after having a quick tinker it looked worse :lol:....:sadeyes:

Any way here it is :)

The Trifid nebula (http://www.pbase.com/strongmanmike2002/image/155999986/original)

Satisfied anyway after a long clear all nighter :D :drink:

PS. as usual...no darks and no flats :D

Mike

[cybereye]

Mike,

How cool ending a three image session with the Trifid Nebula! :thumbsup::thumbsup::thumbsup:

I especially love the Ghost of Jupiter image...

Cheers,
Mario

[Regulus]

Wow, a Trifecta. Gotta be happy with that. Nice images Mike

[el_draco]

That Jewelbox alone is amazing. Love that cluster!!

[batema]

Beautiful Mike. What a great all nighter. Bring them on!!!!!!

[David Fitz-Henr]

Well, you've mixed it up well with three different objects (planetary neb / star cluster / emission/reflection neb) - all in one night with a bright moon and they all look quite impressive; great detail in the Ghost of Jupiter for such a small object, Jewel Box looks nice (good to see an open cluster for a change of pace) and the Trifid looks brilliant with nice colour! Maybe as you say the stars were a bit bloated in the Trifid, though at the fine scale you're shooting it looks pretty darned good.

[strongmanmike]

Yeah it was tri-ific...shame about the conditions but in the end not every image needs to be a masterpiece and it was good to be out in the dome with a beanie on again :)



Cheers Trevor



Cheers Rom, yeah we tend to forget about open clusters huh?



Gotta love all-nighters ;)



Cheers Dave, I guess the 12" and F3.8 helps to be able to gather enough image density to get three images in a night...and they are bright objects too of course.

Not long ago it was quite common but in this age of, unless it is 30+ hours why bother, that we find ourselves in, shooting three objects in one night is rather rare :)

Mike

[h0ughy]

lovely work Mike - very envious of your efforts

[Joshua Bunn]

Great work Mike, The Ghost of Jupiter and Jewel box look brilliant.

[strongmanmike]

Ah sigh...if only I had massive floodlights outside my observatory too, you are so lucky Houghy, soooo lucky...:rolleyes: I hate Bunnings :mad2:



Cheers Josh, yes I was very happy with how the Ghost of Jupiter came out, there are very few amateur images out there that show it any better really and certainly none that weren't taken by a big aperture long FL RC on a high steady air mountain :) and I think my Jewel Bx compares ok to todays APOD too :thumbsup:

Mike

[atalas]

Nice work Mike.

[SkyViking]

Nice collection you've got there Mike, and all in one night :thumbsup:
The details in the planetary is rather good and it's always nice to see a solid Jewel Box image.
The Trifid rounds it up nicely - always a lovely target! :)

[alpal]

Very nice Mike but this is the standard I expect from you now:

http://www.cosmotography.com/images/lrg_ngc6514.html

Only joking :)

cheers
Allan

[Shiraz]

particularly like the Ghost and the jewelbox - even the seeing-demolished trifid looks OK. Great outcome for a single night - must have been very enjoyable. regards Ray

[marc4darkskies]

Mate, that Ghost is frighteningly detailed:thumbsup: and your Jewel Box is glittering with gems:thumbsup: ... Top notch stuff! :thumbsup::thumbsup:

But your Trifid ... as you probably already know, and to be polite in an IIS PC kinda way :P ... needs reprocessing with a completely new set of data under much better seeing conditions :ashamed::whistle:. When the seeing is that bad (quite often in my neck of the woods) I go to bed.

Cheers, Marcus

[astronobob]

ha ha, Mike, you have lowered the bar for the minority of us casual dudes, still too high tho :poke: Them stars are still half as big as mine :thumbsup:
Great to hear you got a fix of soughts all the same. Great results for them conditions, thanx for showing and all the best with the MEGA DATA project :whistle: :question: :cool2:

[gregbradley]

Love the first 2. The Jewel Box I have often found to be a frustrating target and yours is very nice indeed.

Funny your seeing was bad that night if it was Fri,Sat or Sun night the seeing at Bigga was sensational all night. Some of the best I have had for ages.

Greg.

[strongmanmike]

Thanks for the comments guys :thumbsup:

Yeah the Trifid is..?..shall we say...rather under whelming?.. and yes I knew that (and said as much). Hey, many primadonnas probably wouldn't have even posted it :lol:..but me?..meah, I don't care, it was the best the conditions allowed and it was a only a couple of hours of data and under a solid moon with garbage seeing :lol:

All good

Mike

[RB]

Now that deserves one great big Greek "opa" !

:stargaze:

RB

[LewisM]

Good stuff indeed, and I agree with the others.

M20 though... looks like something I'd do (maybe not even that good) :(

[strongmanmike]

Geiá sou! :thumbsup:



He he cheers Lewi

Geee, that bad huh?...gulp :lol: :thumbsup:

Seriously though...the conditions were rubbish buuut I needed a fix :camera: :nerd:

At least it is better than this recent APOD (http://apod.nasa.gov/apod/ap950723.html) :lol: :D

Mike

[Elio]

Great result in that conditions, I know you are capable to make it better :rofl:

Looking that APOD-M20... your could be selected for APOY :D

[Rod771]

I think they're pretty darn good. Especially the Ghost of Jupiter image, that's a cracker!

We gotta deal with what mother nature dishes up. :windy: I think if we held out for a cloudless night with no moon and perfect seeing (and not a school night :P), the withdrawals would be insufferable.

Nice work Mike! Glad you got your fix :thumbsup:

[strongmanmike]

He he, "Image of the Year 1995" yeah baby :lol:



Cheers big ears, I was happy with that one :)



Eeeexactly :thumbsup: aaaand I have always had no problem posting less than perfect images (I have a few ) I know the good ones inevitably come along ;)



Me too :D

[strongmanmike]

Just reworked the Jewel Box to bring back some of the star sparkle and improve the contrast just a tad, the cluster stars in the first version were a bit flat and I've added a 100% close up crop too, to peer deep into the cluster :thumbsup:

Jewel Box (http://www.pbase.com/strongmanmike2002/image/156000018/original)

100% crop (http://www.pbase.com/strongmanmike2002/image/156026124/original)

It really is a gem

Mike

[RickS]

Two out of three ain't bad, Mikey :thumbsup: The Ghost is my pick but the Jewel Box is very nice too. M 20 isn't that terrible either. Both jets are clearly visible so better than a lot I've seen...

Cheers,
Rick.

[LewisM]

That APOD is 1995, so lets not get too judgmental ;-)

Still, like I said, your M20 is better than my confuddled bat guano B-)

[alistairsam]

Got to love that F3.8.
Sweet results Mike, only issue I could find, and I had to look ..

typo - "Guide Camera: Starlightxpress Loadstar "

;)

you seem to favour the SX694 a lot more than the big 16803. How do you think it would've turned out with the FLI? just curious...

Cheers
Alistair

[strongmanmike]

:lol: cheers Ricki, you're just being kind :thumbsup:

Yes the Ghost came out nice I think :)



Hey even for 1995 it is still rather crap, imagine going back in time with our gear now and submitting :lol:



Sorry..what';s wrong with that? :shrug:

As for the ProLine16803, well, the field of view would have been MUCH bigger that's for sure :lol: has twice as big pixels compared to the SX ...it will be coming back when I eventually get a longer FL well corrected instrument ;)...or if that takes too long I may well put it back on the AG12 but I will need to get a MMOAG fitted :thumbsup:

Mike

[cometcatcher]

The thing is Mike, you got the best images possible under poor seeing and moonlight. For that you get nothing short of 10 out of 10. That skill is needed for comet hunting. Comets don't wait for ideal conditions, we often have to image them under moonlight, low altitude, bad weather, twilight, poor seeing, the works. This is why you need to join us comet hunters. ;) You would be great at it!

[strongmanmike]

:lol: Cheers I'll think about it, thanks for the support :thumbsup:

Mike

[strongmanmike]

New improved Trifid processsing (https://www.flickr.com/photos/strongman/14370310962/in/photostream/lightbox/)

:)

[alistairsam]

Loadstar -> Lodestar

The new improved trifid looks great. A lot of us would be chuffed with that.

cheers
Alistair

[strongmanmike]

Ahhh didnt evun realize theer wos a diffrunt speling :P

[marco]

A very nice collection of images Mike, my preferred one is the jewel box. The Ghost of Jupiter looks very detailed (now you should try to go deeper to show the external halos) and the Trifid needs much longer exposure but, hei, with those weather conditions is already a great catch :thumbsup:

Ciao
Marco

[strongmanmike]

Cheers Marco...just about to build the new observatory (http://www.pbase.com/strongmanmike2002/terroux_observatory) so imaging may be interrupted :D

Mike

[David Fitz-Henr]

Actually, this raises an interesting point in that angular pixel size also needs to be factored in when talking about f-ratio speed when imaging. How do we compare your system at f/3.8 and an angular pixel size of 0.84 arc seconds per pixel with say mine (at f/4.8 and an angular pixel size of 1.22 arc secs per pixel).
The following formula could be used to better represent an effective "f-ratio" that can be compared (at least for extended objects such as nebulae):
New f-ratio = Optical f-ratio / (arc-secs per pixel), so:
Mike's System Effective "f-ratio" = 3.8 / 0.84 = 4.5
My system's Effective "f-ratio" = 4.8 / 1.22 = 3.9

which makes your system effectively slower than mine! (so you did a better job with lesser (what's the opposite of mega - mini?) data than you thought :))

Of course, to more fully compare different systems (in general terms at least) you need to consider other factors such as quantum efficiency, camera noise, etc ...


Post edit: Actually, I just realised this only works comparing equal apertures ... I'll have to rethink something for different apertures ... probably should just be aperture x (arc-secs / pixel) ...

[strongmanmike]

Hmmmm? So you are saying because the pixels are wider they are collecting more flux or photons per unit time directly proportional to the F ratio? Seems too simplified to me :question:...Ray?

Mike

[Elio]

I think you should consider the T-Stop also, and much other details as you said...:thumbsup:

I don't trust that big pixels lower the f/ratio in this way, sure you lost details in good seeing condition, dont'you :question:

[David Fitz-Henr]

What I was trying to say was that pixel size is just as important as f-ratio in determining the speed of a system. So, given the same quantum efficiency / camera noise / optical transmission / etc (I know, I know, they're all important too) that, for instance, a 12" f/4 system with 5 micron pixels is the same as a 12" f/8 system with 10 micron pixels, so just talking about f-ratio can be quite misleading.

[Elio]

Sure but not in linear way, I guess... as binning works :)

Sorry form my english, I should be misunderstanded sometimes :thanx:

[strongmanmike]

I think Dave is just musing but may have something...I'm just struggling with the seemingly simple relationship :question:

All very interesting though :)

Mike

[Shiraz]

I'm with Dave on this. The two geometrical/optical characteristics that matter for sensitivity are the aperture (determines how many photons get into the scope) and the angular size of the pixels (determines how many of the available photons get into each pixel).

As Dave points out, a 12 inch f8 scope with 9 micron pixels will be optically indistinguishable from a 12 inch f4 scope with 4.5 micron pixels, all else being equal, since they have identical apertures and pixel angular sizes.

[strongmanmike]

Hmm?...ok, fair enough I guess :question: (all else being equal) :thumbsup:

Mike

[Elio]

That's true, I know, but we have to consider the whole chip area, I thought... in the same chip area smaller pixels are double than biggest one so the qe lost by one could be gained by next, I guess...right?

[David Fitz-Henr]

You are correct Elio in that the same chip area will collect the same signal irrespective of the pixel size, but in the scenario where one camera has pixels double the size of the other camera, the resultant image will then be viewed at half of the size of the other (assuming the same output display device / pixel size is used!). So, the same SNR (neglecting read noise / etc) of the object is being represented at half the output display size. So ... speed has been increased at the expense of detail which has been convolved (lost).



"all else being equal" - yes of course camera read noise, QE, etc will have some impact, and the analogy in the old film days would be film speed, hypering, etc. The difference being that film was a consumable item in those days and when people used f-ratios as a benchmark to compare the relative speed it was understood that film speed also had an impact, as well as optical efficiency (eg. size of central obstruction, etc), etc. Nowadays the CCD is an expensive and integral part of most people's systems (certainly not a consumable like film!), so ... you are right in that I was musing about a simple way to represent the relative "speeds" of systems out there by taking the pixel size into account as well :):P
I probably confused things though with my first clumsy attempt at adjusting the f-ratio (which was incorrect - too late at night for such musings :lol:).
OK, probably enough musing for a Sunday night :P:rofl:

[strongmanmike]

Hey, it was a good muse :thumbsup:

Mike

[Elio]

I'm sorry David but I can't find correspondance in what you said... looking at hystograms of two different shots taken with my taka fsq85 @f5.3, one using an eos 1000D (pixel size 5,7) and one using eos 60D (pixel size 4.3), i should find the first much more illuminated than the second, but it doesn't... :help:

[David Fitz-Henr]

Hello Elio, the histograms show different profiles and appear to be for different areas of the sky, and are also from cameras that may have different QE's, etc. Remember that my comments are qualified by "all other things being equal", which does not appear to be the case here.

To further clarify my musings though, I was not attempting to fully quantify the difference in imaging systems, such that one can take two similar systems and give an absolute ranking of speed between them. Rather, I was pointing out that when qualitatively discussing different systems' speeds (eg. this is a "fast" system, this is a "slow" system), that one needs to also include the pixel size in the equation as an important part of the comparison (in addition to aperture / f-ratio which is often used alone). In this way, we have at least covered all the major optical/geometrical properties of the imaging system; of course, if we include quantum / electrical factors (such as QE, cooling, read-out noise, etc) we will get an even better comparison, but this tends to be impractical in forum discussions so people will generally factor in the advantages of various cameras (eg. OSC / DSLR / CCD) based on their knowledge of the camera used.

As you mentioned English is not your first language, so you may have taken me too literally on some of my musings; You are correct, and as I have said, that other factors (eg. QE, cooling, read noise) will have an impact as well; this can of course lead to one system with slightly larger pixels being slower than a similar system with smaller pixels as you suggest. :)

[E_ri_k]

Nice one! Great to get 3 in one night! I'd be lucky to get a shot of the moon at the moment with all the cloud!

That Ghost of Jupiter in really nice, it's an awesome colour, good amount of detail in it too :)

Erik

[strongmanmike]

Thanks Erik :thumbsup:

Lately the weather, moon and life have meant that I haven’t managed to get out as often as I would like to.… so, I have made the most of the limited time by utilising one of the major benefits of this scope and that is its aperture and speed, both of which contribute to getting decent images in a single night :prey:

In the end astroimaging is meant to be enjoyable and sometimes I just want an image with minimal fuss, not all images have to be ball breakers :)

Mike

[E_ri_k]

Agreed Mike, it's great to just spend time under the stars, and get an image of something out there :)

Erik

[strongmanmike]

Yep, that's it, the good nights will come when they are ready, enjoy the activity and as you say, just being out under the stars (even in a dome :))

Mike