The Ghostly Tower - AG12

[strongmanmike]

These clear skies are nice...

Here is a 6.25hr exposure with the Mclaren Scope ;)

This is a deep narrowband image processed to resemble an HaRGB image.

Friggin SH*T seeing :scared:...I was begining to think it was local seeing in the OTA until I had a brief 1hr or so of good seeing - unfortunately this happened while I was doing the RGB which of course contributes zip to the resolution :doh:...the guide scope star was balooning in and out too so it ain't the Mclaren Scope (http://www.pbase.com/strongmanmike2002/image/134718521/original) (thank god)

Here's the whole album, click on the thumbnail you want to look at and then scroll to the very bottom of the image page and select "original" size.

The Ghostly Tower (http://www.pbase.com/strongmanmike2002/dark_tower)

Feedback welcome :thumbsup:

Mike

[Bassnut]

whoa, the full frame "50%" res is just awesome (50%? whys that, dont get that), but well done right there. Tight as and full of detail. Top work Mike.
Mclaren scope?, geeze, really?, and the scope pic is a bit of overwhelming advertising, messy.

[coldlegs]

Mike
Love the 50% frame. Heck they are all great! Couldn't help noticing the "truck differential" weight on the mount. What's the all up weight of that lot??
Cheers
Stephen

[strongmanmike]

He he..always wanted a fast scope (seriously..you don't get that little F1 humour then?).

I display the full frame at 50% res ie approx 2000 X 2000pix just for the convenience of the viewer ie less download time and not as much scrolling required, hence the addition of the various crops :thumbsup:

Mike

[strongmanmike]

You know what?...I don't know the weight exactly, I must weight it some time, suffice to say there is about 40kg of counterweight on there (I need some nicer weights to add huh? :lol:). Still turned laser guided autoguiding even in a stiff breeze at times and poor seeing with a fat Newt on board too!...The NJP is an amazing performer!

Glad you liked it Stephen :thumbsup:

Mike

[RobF]

Great work Mike. Glad to hear the beast has been for another spin around the track. I'd be interested to hear more about how you managed to get false colour NB to look so close to RGB too if you could? Nice result, even if you were frustrated by conditions - looks fab to us mere mortals.

Cool bumper stickers by the way too...:D

[atalas]

Very nice Mike.

[Lester]

Wonderful image Mike, but still looking forward to what you will get with good seeing. All the best.

[h0ughy]

A Mclaren scope - does it look good in a kilt ?- no dont go there i know you have one....... but you certainly have the advertising for it. Are you selling space on your freezer suit for the smaller sponsers ;)
Except for the bloom around the very bright stars its a cracker of an image. I have to say that the seeing over us has been horrible, the other night i saw Rigel twinkle from blue to red - overhead. Love the work - impresses me no end - oh goodness i see that figure in a kilt again....

[multiweb]

Pretty awesome field Mike. You've got the beast ticking now. :thumbsup:

[Peter Ward]

Mclaren make some cool cars.

But so do the mob from Maranello....I think I like them better

Nice piccy by the way :)

[strongmanmike]

Cheers Rob

The final colour balance is pretty cool huh...? Not sure I could describe teh steps in an orderly fashon taht would make sense, suffice to say a lot of blending went on (like a good Scotch blend) - It was a spaghetti Bolognese recipe in PSCS3+ :P..I process like I cook, as long as the flavour ends up nice the route there is almost black magic at times :lol:

Hopefully the "fast" scope connection and the fact that she was made in England will make sense of naming her McLaren Scope .. :question: :lol:




Cheers Big Louie



You and I both :thumbsup:



Good to hear that I wasn't the only oen with poor seeing (not good for you, I didn't mean that) as I sadi I was starting to think it was the scope and the fan/heater arangement :eyepop:..when I saw the colour frames coming down tight-as I though man, where was this when I was taking the OIII - it was like blur city for those subs :rolleyes:..but I breathed a sigh of relief knowing that the scope can see things quite sharp after all...phew

Kilt?...I haven'tworn the kilt for a number of years now...don't have one anymore either :(



Cheers Marc, it's ticking for sure but it should be able to purrrrrr and I am getting closer :thumbsup:



Yeh well she's British so I thought McLaren (although I think they started out in NZ :question:) more appropriate than calling her a Ferrari :rolleyes:...of course I would like an Officina Stellare scope for sure ...theeen I would call it a Ferrari :D zooom

Cheers

Mike

[David Fitz-Henr]

Very nice image Mike, especially considering the poor seeing; good stars right to the corners! 40kg of counterweights!!??!! Really? Given that the scope weighs about 16kg and the camera is hanging in line with the polar axis I guess then that the guidescope must be quite weighty? Just looking at the setup - with the guidescope on one side of the scope and no corresponding counterweight on the other it must give you a few balance problems at times?

Edit: Actually looking more closely I can see that you have offset the saddle to one side so the lateral balance is not an issue!

[strongmanmike]

Hi Dave

I'm getting there...

I use an Orion ED80 refractor and SXV-H9 guide camera.

The ProLine and CFW-5-7 and corrector weigh a bit too

Yes the OTA is off set and so is the camera a bit (rotated about 10deg), I moved the guide scope forward too so it would be held more centrally and rigidly and doing this meant the scope became front heavy (can't move the scope back in the cradle anymore or the CFW will hit the NJP head) so I had to velcro and tape some weights to the back of the mirror cell back plate so this meant more counter weights...:rolleyes:

I just want some good seeing :sadeyes:

Mike

[gregbradley]

That's a very good image Mike. Stars look pretty close to perfect now. The small distortions are very minor indeed now. As you say perhaps a little bit of flex. One way to tell would be to take an image and then move the camera around so the flex would be in the opposite direction and take another image and compare them.

Your fast scope seems to have picked up a river inside the river of Ha. Like a slightly golder orangy nebula in the middle of the stream. Also a slight golden glow at the edge of the dark tower.

Your stars are nice and bright and colourful.

A very nice image.

Greg.

[marc4darkskies]

Mmmmmm ... beautiful shot Mike!! Stars look good to the corners too - top stuff!! That black beauty of yours is starting to hit her stride!

My only small critique (and maybe this is personal preference), is I don't much like the bold reflection halos around the bright stars.

Cheers, Marcus

[strongmanmike]

Cheers Greg

Some work to do, but going on the results and experiences of others with these fast newts and big cameras, it is able to be nailed down so I have faith :thumbsup:



Thanks Marcus

Yes I'm still improving :P

As for the Halos...nuttin I can do about that mate :shrug:..It's all about compromise I guess, besides...it's like I have my very own little UK Schmidt camera! :D

Mike

[prokyon]

Hi Mike,

great shot of a fascinating (and spooky :) ) object. Did not know it before. Thanks for sharing.

Cheers

Werner

[Hagar]

Very nice Mike. A new scope takes some time to come to terms with it's intracacies such as focus and balance. I am sure given some time it will all become a lot easier.
Looks like it is a solid performer and just what you were after. So far the results speak for themselves and I'm sure your results will improve with better seeing etc.
Lovely work as usual.

[iceman]

Really nice Mike, a very busy area!

[marc4darkskies]

Why not? A little processing would remove them ... unless, that is, you actually don't mind them. :shrug:

[strongmanmike]

Oh yeh of course...I meant they are there from the optics.

I have tried removing them in Starfire images before but was never happy with the result, always looked like they had been processed out so I just got used to them...any tips here? :)

Mike

[avandonk]

I would take an identical field with the Starfire and do a HDR between the two where the stars would have very faint vestiges of the so called haloes but still have the beautiful bright nebula data from the AG12.

Bert

[Stevec35]

Nicely done Mike. The main thing that stands out to me though are the haloes around the bright stars which seem a tad unsightly. Of course there are techniques for minimizing them.

Cheers

Steve

[strongmanmike]

You kidding me Berto :eyepop:...it's a major operation setting the AG up as is..let alone having to reconfigure everything for the Starfire :lol:..be a dream to have'em side by side on a PME in an observatory though, with two ProLines :thumbsup:

I'll have a play with the data tonight, see if I can do anything to the brighter halos...last thing I want to do is butcher the stars and make'em worse...:rolleyes: :lol:

Mike

[marc4darkskies]

Would you consider this an improvement? ... Coupla minutes per halo.

[strongmanmike]

Hmm yes, that looks pretty good I guess :question:...ok so what simple method did I ignore all this time then :doh::lol:

[multiweb]

Yeah I'm interested in the processing of these too. I get heaps with my MPCC. :question:

[marc4darkskies]

Start with flattened layer. Duplicate it twice. Make the top layer invisible for the moment.

Middle layer: apply strong median so that all the little stars dissappear completely and the large haloed stars still appear as a faint smudge. I used 25 pixels or so for your 50% version. Be carefull with your median radius, you can overdo and underdo it! Create a hide all layer mask. With a soft edged white paint brush on the layer mask, carefully "reveal" the median layer only over the bright halo so that it and the star are completely gone. Be careful not to hide any residual stars at the boundary of the halo.

Top Layer: Create a hide all mask for this layer as well. With a soft edged white paintbrush, paint the layer mask with a spot centred on the star. Reveal as much of the airy disk as you like. With a very fine white brush you also need to paint the mask to reveal the diff spikes as well. This last step is best done while sober.

Touch up: If the colour where the halo was isn't right, apply a circular marquee tool (feathered) to that area on the middle layer, and colour balance until it looks right. If you've hidden some boundary stars, gently paint the mask in the top layer with a small soft white brush to reveal them.

Repeat the process using the same layers for all affected stars. Make sure you zoom right in of course so you can see what you're doing.

Voila! about 2 mins per star should do it

[Octane]

Excellent result, Mike. Humming along quite nicely by the looks of things. :)

Now, where do I find me some clear, cloudless, new Moon nights, without work and/or other annoyances?

H

[John Hothersall]

Wonderful results from terrible conditions - this is still a good test, imagine when things are vgood. I think you are in love.;)

John.

[Satchmo]

Just out of interest Mike, what do you think is the source of the spherical halos around the brighter stars ?

[strongmanmike]

Marcus...have I mentioned I love you? :love: :thumbsup:

Mike
err?..man love...:ashamed: :whistle:

[strongmanmike]

Once I have the residule collimation/flatness sorted 100% I do think I may sleep with her :evil2:



No idea



Humming Humi yes, but purrring is what I really want ;), this scope is capable of a little better I think..?

Mike

[DavidU]

Very nice Mike ! The Aston Martin is one fast instrument.

[strongmanmike]

Considered that name Dave actually but went for the McLaren F1 instead.. even faster :thumbsup:

Mike

[Leonardo70]

Very interesting object .... and a very good image Mike ...

All the best,
Leo

[Phil Hart]

I'm with Marcus and Greg.. you'd have to be very bloody happy with those stars now. Geez f3.8.. Sweet as..

Phil

[Peter Ward]

[QUOTE=marc4darkskies;721263]Start with flattened layer. Duplicate it twice. Make the top layer invisible for the moment.............. /QUOTE]

While I have no problem with instrument artifacts ( in a sense they give a hallmark to an image) I do have a problem with localised image manipulation.

Are you taking pictures of deep space or painting them?

Sure you can paint any picture you like, but is this reality???

As I have mentioned many times before....Cindy Crawford has a mole... yeah
right....photoshop can fix anything....except it wouldn't be Cindy.

[Ross G]

Wow...have never noticed the mole!

[strongmanmike]

Thanks Leo, getting there...



Yeh happy enough Phil but some improvements still to come though I think? :)

[QUOTE=Peter Ward;721389][QUOTE=marc4darkskies;721263]Start with flattened layer. Duplicate it twice. Make the top layer invisible for the moment.............. /QUOTE]



I know what you are saying Peter and artifacts from optical configurations bother me very little, in ths case though the ajustment is pretty minor so I think it is acceptable :thumbsup:...Marcus's method isn't as easy as it looks either (for me anyway :lol:) to get a natural look, he has clearly had experience with this technique...my quick go last night didn't look as good as his effort :question:

Mike

[marc4darkskies]

What?! You don't use layer masks when processing? :question::shrug: If you do, that is in fact "localised processing".

I'll bet if Cindy had a black eye you might want to help her. :lol:



No mate, I don't get reflection artefacts this severe so it's not something I need to do. My green filter tends to cause some noticeable reflection from time to time but the others don't. If I find that objectionable, I'll colour balance and level it out. Other than when the artefact overwhelms the space around the star, you wouldn't use median filtering like this - it's very destructive.

[strongmanmike]

Well, I tried it last night and my result wasn't as good as yours :shrug: :sadeyes:..I had trouble following your instructions actually, perhaps a mouse click or two missing there somewhere (or assumtipons made about my PS efficiency :lol:)...anyway I was pretty tired last night after some all nighters over the weekend so I'll try again when I am fresher with fresher more patient eyes :thumbsup:

Cheers

Mike

[Moon]

From all the many images I have seen, those reflections are normal for the Keller/Wynne corrector. There was a discussion on the astrooptik web site about it - the info has been removed recently but you can still read it using the internet wayback machine: LINK (http://replay.web.archive.org/20090421185853/http://www.astrooptik.com/sonstiges/Newton3Inch/NewtWynne.htm)

There is also a brief discussion here: LINK (http://www.heavensgloryobservatory.com/RC%20Talk.htm)

I have one of these on order, hopefully it will be here soon. When it gets here I'm fully expecting some halos, but I won't be processing them out - but that's just me.

The only alternative I know of that comes close was the Paracorr STL (now out of production). It works well, but it's only 2 inch and hence causes too much vignetting. Hence it's a non starter. On the positive side, it's doesn't have halos. Example images here (http://deepspaceplace.com/images.php?sort=&filter=AT8IN).

As always it's a compromise.

James

[strongmanmike]

Congrates on the impending scope James, what is on its way exactly? What's the ETA? :)

There are none of the reflections detailed in that Keller corrector link visible with the Orion Optics Wynn corrector in the AG12, so that's good, just the bright ring halos around the brighter stars.

Mike

[Moon]

A 3" Wynne corrector. It should be here any day now. Hopefully they are reading this! I'm planning to put it in my GSO 12" f/4.

I know it's a different product, but to my eye all the images here (http://www.astrosysteme.at/eng/gallery_12Zoll.html) have a very similar halo. I always assumed it's some type of reflection, but perhaps not. It would be interesting to do a test like the one done by Brian Lula.

James

[Paul Haese]

Nice image Mike. Halos or not I like the plethora of stars and the star shapes are a lot better. Looking forward to more.

[strongmanmike]

Ah yes this is teh GSO 12" F4 in the equipment thread, ooooh fun times ahead there :thumbsup:



A lot of those shots are a few years old of course..?

Mike

[strongmanmike]

Yes you and me both :thumbsup:..

[gregbradley]

They are fairly easy to fix really.

Duplicate layer.
Circular marquee tool Hold down the shift key and drag the lasso to the right circular size. Drag the circle over the offending star.

Feather it say 5-10 pixels. Control H to hide it (its distracting) control H again brings it back.

Use the selective colour tool. click on neutrals. Now use the sliders to reduce the offending colours. Then tweak it more by selecting the colour that in the halo - say blues and cyans. Work on it more.

Then you can also use - sponge tool set to desaturate, you can also use the healing tool set to colour or luminosity (not normal).

You can also use curves to make the star less bright.

Then deselect or drag the circle over to the next star to repeat. You could record it as an action on one star then drag the circle on to the next one and use the action to save time.

I did this on my recent Dark Tower image and it worked well.
It may not be as well known that the healing tool can be set to colour or luminosity rather than normal where it affects everything around it.

Greg.

[SkyViking]

That's a spectacular image Mike. And those orange hues are pretty interesting and really add an extra dimension to it.
Seems like you have calibrated the new scope to perfection now. Only those prominent halos detract a little (very little), but as others have suggested it should be possible to process them out - which I think is perfectly fine to do.

[Peter Ward]

I have 3 UK schmidt glass plates...now framed and backlighted.

The brighter stars have halos.

This is what tells me they came from the schmidt and makes them so sublime.

I suspect these, now quite rare, works of science are becoming art/collectables. ;)

[mill]

Yeh right you only notice two other cold water moles :P

Ps Mike your pic looks just like Cindy, beautiful :)

[strongmanmike]

Ah sigh...to halo or not to halo that is the question...?

I am with you on this one Peter, know exactly where you are coming from, I have a similar feeling toward sattelite trails in images for the same reason.

Mike

[strongmanmike]

Yeh the two blue stars close together at the bottom of the image look like..:question:....her other two distracting assests :whistle:

[Phil Hart]

i noticed marco had halos that look almost identical in his widefield shots with the Pentax lens.. a very different optical system. he is using the same camera though. perhaps it is a reflection between the sensor glass and the filters? i wonder if marco and you have the same filters in your FLIs?

[strongmanmike]

Interesting Phil, I'll look into it :thumbsup:

Thanks for the interest

Mike

[multiweb]

Correct. I too believe it's something very close to the sensor. My guess would be light that bounces back and forth on to the large glass corrector inside the drawtube reflecting back to a piece of glass that is closer to the CCD. It'd be good if Mike could post a cross section of his imaging train at the focuser level and post it. I'm sure somebody will analyse the light path and pinpoint the problem. JasonD's (Catseye whiz) is pretty good at raytracing.

[gregbradley]

Its unlikely its between the filters and the CCD chamber window (which is antireflection coated fused quartz on a FLI Proline). It would show in other images on the AP scope which it hasn't.

It is more likely to be between the filters and the corrector.

When 16803 cameras first hit the streets from Apogee U16M and FLI Proline 16803 (the first 2) there was a lot of internet posting about reflections visible in flats.

It boiled down to reflections between the filters and the correctors/flatteners.

The chip is so large that basically every scope needs a corrector/flattener for it to work. This then showed up the high level of reflectance off of the then various filters.

What happened is you had most of the filter manufacturers come out with new antireflection coatings on their filters. Apogee added an aperture mask to their camera as well. Most blacken the edge of their filters with matt black paint to further reduce reflections. Square filters can have uneven edges that cause reflections.

As Mike has not had trouble with his antireflection coated Astronomiks Mark 11 filters I suggest his O111 or S11 or even Ha are not antireflection coated and hence the reflections.

If you used O111 S11 and Ha filters that are coated this most likely would go away.

It is almost certainly reflections off the narrowband filters (which look like mirrors) back and forth off the rearmost corrector lens.

By the way is the corrector AR coated and if so is the rear facing element AR coated?

Not really that big of a deal really. If it were in your LRGB images then it would be.

Greg.

[strongmanmike]

It's not as easy as that Greg, using the PL16803 with the AP (which had a big flattener about the same distance from the CCD/CCD window 86mm v 78mm) the L and Ha filter showed almost no halo but the RGB all did, with the AG12 and PL16803 it appears the RGB and L give very little halo but the Ha shows the small solid halos. I got similar small halos with the Ha filter and PL11002 with the Starfire, so it is not as easy as it looks to tell who the real culprit is...?

The Orion corrector is ED glass, fully coated and the elements have blankened edges.

In the end, as Peter Ward says, optical diffraction effects are sometimes just trade offs for other capabilities I guess..? Having said that there may still be the ability to mitigate the effect...soooo you know anyone with a set of Astrodon genII 50 X 50 filters I could borrow for a little while to test the theory...:whistle::prey::prey::prey ::prey: :D

Mike

[gregbradley]

I see.

Your Astronomiks are they the latest Generation of AR coated filters or the earlier ones? (which were pretty good compared to the mirrored type filters like Astrodons and Baaders).

Greg.

[strongmanmike]

They are the latest low reflection variety, as I said with the Starfire and 4" flattener and the 16803 and testing on Alnitak the Lum and Ha were virtually halo free, the RGB not so, this seems to have been reversed with the AG12...?

I plan to do a more diffinitive test tonight just to check what I am getting exactly.

Mike

[gregbradley]

One simple thing you could try is to make a mask for the Proline's CCD window. A bit of black cardboard that Newsagents sell for kids school projects. Cut out an opening the same size as the chip and tape it over the window. The Apogee camera had a professionally made black alumiunium mask like this they sent me to retrofit to reduce reflections.

I think it helped. Not a perfect fix but a simple one and it may help (it also may do nothing!).

Greg.

[strongmanmike]

Doesn't make sense how that would affect halos though.. spurious off axis reflections perhaps but not halos, halos result from direct back and forth reflections as far as I am aware and a mask would do nothing to mitigate these...would it :shrug:

My Proline 16803 does have the chip mask

Mike

[gregbradley]

Yeah you're right there. It'd be between the filters and the corrector.

I don't see any with the CDK beyond usual and that also has a corrector.

So I imagine the right combo will get rid of those halos.
Its one reason I switched from Baader to Astrodon Gen 11 filters. They seem to be a big improvement on reflections.

Greg.

[Peter Ward]

London to a brick the halos are an artifact of the field corrector.

Take a pic without the corrector...... Might be a little ugly at the edges....

[Jen]

:eyepop: very nice Mike :thumbsup::thumbsup::thumbsup:

[renormalised]

Can't remember if I commented earlier on this pic, but anyway, nice shot, Mike. "The Ghostly Tower" sounds like an episode of Harry Potter!!!:):P:)