Ah yes, now I remember all the dramas I had the last time I imaged the Horse Head.
With my relatively narrow fov, I think the next time I will plan on doing a mosaic with Alnitak in the fov to save all this drama!!
Yes, good ol Alnitak... and then the 3.8 mag star Hip 26549 just above decided to get in on the act as well.
Thought I had it covered till I started downloading the colour channels.
Man what an adventure down stretching my PS knowledge!
The compiled individual r, g, b's were like looking at a well unfocused bright star.. the worst being in g & b channels.
I masked and layered, and then some, been the hardest repair job I've ever struck.... nothing in any of my astro processing programs could fix this up well... not even in Pixinsight's DBE, my favourite fall back..
Any one with some ideas??
It still looks a little like a dogs breakfast, but it's the best I could come up with at present.
Hitting the thumb nail will take you to the hi res version 2.2mb. http://www.baytop-observatory.com/
All the best for now.
Rich... with a few more grey hairs
Don't beat yourself up. Alnitak's right round the corner and not going anywhere. Everybody knows that. I reckon it's a terrific shot. Colors and details are superb. One for the pool room
Don't beat yourself up. Alnitak's right round the corner and not going anywhere. Everybody knows that. I reckon it's a terrific shot. Colors and details are superb. One for the pool room
Thanks Marc, yeah I do realise Al's effects... but didn't think it would be as bad as this..
Here's a 50% reduction of my blue composite to give you an example... the other channels were as bad.
A real night mare to process. I used a compilation of 1' lum subs I took by mistake and used this as a background layer to the individual r, g, b channels... but had to adjust top and bottom of each image to respective shades to ensure that I would have close matching colour to my stars, not just white blobs... and to try and represent a close colour match to the reef and surrounding areas within the affected area.
So yes it was a real challenge.
I'd certainly be happy to hear from any one with a more effectiver way to cleanly remove this artifact..
I was really happy with the data apart from this though.. and just happy to be out of course.
Using difference layers/thresholds then multiply blend you can match the highlighted areas to the natural background. See attached. Then all that is left to do is to feather the mask and blend the edges in but your halos have patterns and sharp edges. See attached.
Maybe someone knows how to get rid of them in that last step. I'd be interested in learning how to do that too. I suspect another divide like a flat fielding operation of some sort.
Thanks Marc,
i had tried this as well as other methods like layers/ selective masking/levels/ curves to match the predominant area. While this worked fine, it always came down to the defined sharp edges and spikes that I couldn't get right.
Must be a way similar to dividing a flat frame away.. by creating a starless/ detail less flat with only the reflection, then dividing from the original... I think there must be a solution.
But search I have done and nothing has come up.
Oh well.
Clearish tonight, might do a run of rgb's with Alnitak in the fov and stitch it to the present image.
I could get it more perfect with more time but it is resolving with what I have done already:
1. duplicate layer set to difference
2. opacity slider to suit.
3. layers/hide all/paint brush set to about 25% and foreground set to white
4. run in the areas of the reflection only.
5. flatten image
6. Healing brush set to luminosity and smallish size brush. Do small areas at a time and not necessarily always straight lines, avoid the stars.
7. Alternate as needed with dodge tool (to brighten darker lines of the reflection) and burn tool (to darken lighter areas of the reflection).
Take your time, zoom in and set the brush diameter smallish and don't go at it too hard or it will stand out.
8. Curves to rebrighten the image a bit as it got darker in steps 1-4 above.
Mirrored scopes seem to suffer from reflections more than refractors.
My Planewave CDK17 is quite prone to this hence the above.
is your secondary mirror housing flocked? I am thinking of doing that to the CDK. Or perhaps a bigger secondary baffle? The CDk has 4 secondary baffles and still gets reflection/spikes although not like that where you see the spider and secondary mirror more of a light flare. Hence the healing brush set to luminosity as it is more of a problem in differences in brightness than anything else.
H, a big new years cheers to you. Thanks for the very kind words.
My 10" Richie Creation is a great scope when it is attentively looked after.
I am also very happy with what the Paracorr has done for my stars.
I think the ol' girl has hit her mark now.
Hey, what's happening with your new set up ??
Are you still waiting for parts..
Am looking forward for when you get it happening.. hopefully very soon.
All the best for the new year H
Always appreciate your comments!
Quote:
Originally Posted by gregbradley
Hi Rich,
Mostly fixed.
Do I win a prize?
I could get it more perfect with more time but it is resolving with what I have done already:
1. duplicate layer set to difference
2. opacity slider to suit.
3. layers/hide all/paint brush set to about 25% and foreground set to white
4. run in the areas of the reflection only.
5. flatten image
6. Healing brush set to luminosity and smallish size brush. Do small areas at a time and not necessarily always straight lines, avoid the stars.
7. Alternate as needed with dodge tool (to brighten darker lines of the reflection) and burn tool (to darken lighter areas of the reflection).
Take your time, zoom in and set the brush diameter smallish and don't go at it too hard or it will stand out.
8. Curves to rebrighten the image a bit as it got darker in steps 1-4 above.
Mirrored scopes seem to suffer from reflections more than refractors.
My Planewave CDK17 is quite prone to this hence the above.
is your secondary mirror housing flocked? I am thinking of doing that to the CDK. Or perhaps a bigger secondary baffle? The CDk has 4 secondary baffles and still gets reflection/spikes although not like that where you see the spider and secondary mirror more of a light flare. Hence the healing brush set to luminosity as it is more of a problem in differences in brightness than anything else.
Ahh Greg, you da man!!
Mmmmm, no prizes, sorry... how bout a big man hug
Nah, thanks a heap for doing a run down for me.
The image looks pretty well cleaned up beautifully!
And with the colour image as well....
All around my secondary is flocked so I expect it was because Alnitak was so close, just sitting just outside the fov.... maybe this was inducing extra effects triggered by the abg on the detector/ sensor... i've seen this before when having a fairly bright star just off the chip when in focus mode. The whole chip seems to compensate for the light increase. Noticed this on all my previous ccd's as well.
I recall when I had a VC200L the same thing would happen with bright stars off the chip. I'd get some interesting flares.
I think it is a lesson re enforced in my brain...
Any ways, I really appreciate your time and effort here.
At the mo am just getting some M78 lum down so in the mean while I will have a go at using your steps and see if I can perfect things.
Cheers Gregg... all the best for 2011.
I tried imaging for the first time since August a couple of days ago, but, the clouds had other ideas for what appeared to be seemingly glorious evenings at first.
Then, my RoboFocus unit carked it. I've sent a support request off to Jerry at RoboFocus. Waiting anxiously to hear back his advice. I posted my woes in the equipment forum.
Cheers, mate. And, congrats once again on a very, very compelling and beautiful portrait of an old favourite. Regardless of imperfections, it's an image which had me looking for ages.
Looks like a very good image to me! Smooth colours, good stars, no noise to speak of, etc.
You dislike your narrow FOV, you should see the data I am getting of it right now, the head barely fits in my FOV at all. Not the beste object for my scope.
Wowser - I'm with the guys that have commented already - that's a fantastic horse, and the Alnitak spikes don't worry me one little bit!
Thanks Rob!
What I started with and where it is now.. had some work to do that's for sure.
But am pretty happy with it apart from the obvious residual reflection left.
Hope you folk up there are keeping you feet dry!
Quote:
Originally Posted by Octane
Rich,
I've got all my bits.
I tried imaging for the first time since August a couple of days ago, but, the clouds had other ideas for what appeared to be seemingly glorious evenings at first.
Then, my RoboFocus unit carked it. I've sent a support request off to Jerry at RoboFocus. Waiting anxiously to hear back his advice. I posted my woes in the equipment forum.
Cheers, mate. And, congrats once again on a very, very compelling and beautiful portrait of an old favourite. Regardless of imperfections, it's an image which had me looking for ages.
H
Glad your gear is all with you now...
Damn, gotta hate that when something dies in the arse when all you want to do is test out new gear. Course the weather will always be a pain too. Hope you get the unit sorted.
Am looking forward to seeing your work posted again!
Lol I haven't been able to get my Focus Max to work properly ever since I've had the Paracorr in... spent too many hours trying to no luck... have given up for now in disgust and am just using the jog function.. a pain for sure!
Thanks again H
Quote:
Originally Posted by rogerg
Looks like a very good image to me! Smooth colours, good stars, no noise to speak of, etc.
You dislike your narrow FOV, you should see the data I am getting of it right now, the head barely fits in my FOV at all. Not the beste object for my scope.
Cheers Roger for the nice comments!
It's not that I dislike my FOV, just with this object... I've stepped up considerably in FOV so 'I no complain'
I hear you about narrow fov's... I remember when I had a F9 reflector and a tiny TC255 chip... was about 330,000 pixels relating to a detector of 3.2 x 2.5mm or there abouts.... when I decided to image the horse head... wow couldn't really find the thing until I did at least 1min centering exposures... even then it was noisie as, extremely faint, the head alone took up the whole chip. And as I didn't really have an effective auto guiding system I gave up and went to something brighter.
Be interested to see your end result!
Thanks all for your comments.
Certainly appreciated
All the best
Rich
It's not that I dislike my FOV, just with this object... I've stepped up considerably in FOV so 'I no complain'
yes, true... I know what you mean, I got my wording wrong, it's just a case of objects vs FOV.
Quote:
Originally Posted by richardo
Be interested to see your end result!
Well I'm sitting here fiddling about with various things while it's taking the pics and have one dark frame now, just barely enough to see what I might get. Thought I might post it as I have the opportunity. No flat or bias. Hope you don't mind me posting it in your thread. I will do a few more light frames then leave it doing darks and go to sleep. Certainly is a tight FOV oh, shot is 10x10min.
yes, true... I know what you mean, I got my wording wrong, it's just a case of objects vs FOV.
Well I'm sitting here fiddling about with various things while it's taking the pics and have one dark frame now, just barely enough to see what I might get. Thought I might post it as I have the opportunity. No flat or bias. Hope you don't mind me posting it in your thread. I will do a few more light frames then leave it doing darks and go to sleep. Certainly is a tight FOV oh, shot is 10x10min.
This is looking good Roger!
Keep going, you'll need a mega amount of data to keep things smooth at this FL. (guess you know that)
Look forward to your finished image posted!
Quote:
Originally Posted by strongmanmike
Can I give it to him? can I? can I? Please
Yes you can Mike, just remember that he's a human being and can break easy... man hug, no bear hug..
Perhaps Jen could do it ...maybe with lots of emoticons?
Oh and nice Horsehead BTW, Gregs fix looks ok actually Some lovely subtle detail showing through there in the faint background/forground clouds
Mike
Yeah, better let Jen do the hugging big fella... or people might talk... just be another rule for CADG to put into their stipulations for members.. what is going on there.. can't people just sort their personal differences out without the bureaucratic bollocks .. nothing like a good punch up over a few beers to clear the air
Geez, am I being politically incorrect again...
Yeah I love Gregs fix... I'm going to give this a good go today sometime.
But Greg has done a great job in the lower L/H corner and around the reflection neb to reveal some hidden detail... the bright blue stars are a little over cooked though but know Greg did this more to show me.
Cheers big fella for the
As usual look forward to your many crops from your latest and the colour to the galaxy group.
lol, Rich! you're on the CADG list? The nonsense is tearing the society apart.
So much for the discussion of astronomy.
H
Hi H...
have been on the list for a few years. Did post a few images there at first, but quite mute response which is fine. I know there are lots of guys doing follow up work and the more scientific stuff.
Since I still get the posts coming in, I do catch up on occultations, minor eclipses and other main stream events.
There's quite a few members that I know through astronomy dealings and emails etc... so good to keep in touch.
But hooly dooly, like you say, what ever happened to camaraderie with like minds enjoy the pursuit of all things astronomy... mmmm
Sounds like a faction is beginning to start.
Good to keep well out of I'd say... although Jack Child did post a very good response.
What a shame..... I've seen this happen to other groups and they die a natural death.
Thanks for the very kind words.
oh, shot is 10x10min.
...maybe with lots of emoticons? 
Some lovely subtle detail showing through there in the faint background/forground clouds 
can't people just sort their personal differences out without the bureaucratic bollocks .. nothing like a good punch up over a few beers to clear the air
