NGC6729 Corona Australis

[Paul Haese]

Well finally got back to the imaging side of things. This image is 10.6 hours of data. The guiding, pointing and stability of the equipment is great. Very happy overall with this image. It needs maybe some more data to deal with the dark dust lane and the noise in that area.

For those interested I would like to point out that you can pull a PME apart and put it back together properly without sending it back to Software Bisque. :P The images I obtained this weekend are proof of that fact. I think I put it back together correctly.;) :D

Take a good look around the image. Try to find the face on barred spiral galaxy.

Click here (http://paulhaese.net/CoronaAustralisTSAQSI.html)for image

Feel free to provide critique of the image. I would like to know how to get rid of the two blue reflections near the left center of the image. I have tried a few techniques without success. The reflections are caused from the star just out of the field of view on the center right.

[allan gould]

Really lovely image Paul. Thought you may have taken it with the 12" but that is a lovely scope and to get the globular with it is just great composition. I like this area a lot and you have done it justice.
Allan

[atalas]

Great Shot!

[multiweb]

Very cool shot. :thumbsup:



Here's one way [from Jase a while ago]:

[beren]

:thumbsup: that's a beauty well done, glad to see the PME tweaks are paying off, good one mate.

[richardo]

Wow great image scale Paul and I love seeing things in full res with the equipment we have these days.. why not I say:shrug:, especially when the guiding is as good as this!
Well done with the mount, total satisfaction doing things yourself.

I pull my mount right down so every bit is sitting on the bench. I have done this twice in the past ten years. I've replaced all the tapered bearings, replaced the worm bearings with ceramic high precision ones.. when I bought it second hand I removed all the spur gears(yuk) replacing the motors and using timing belts, both stepper and servos. Without PEC I now get around 3.2 peak to peak error.. with PEC it is almost a straight line (too bad about my flexure:sadeyes:)
For me living so far away from anywhere, plus most of us from a service centre (if any), it is mandatory to have self serviceable equipment..
certainly can't beat the satisfaction when it all comes together and is better than ever!

Yes those bright stars just outside the fov are a pain with reflections... I have battled similar with mute success. I guess you could mask and feather the area, adjust the colour balance back to some where around the general area. I'm sure you've tried this.
Still it takes nothing away from the image at all.

Nicely done!

Once again, congrats with the mount.
PS.. Am looking forward to your up and coming images from your new 12"RC and ccd setup.

Rich

[Paul Haese]

Thanks guys,



Thanks Allan. Saving the 12 for next month so I can do NGC253 with it and the STL11K I recently bought. So just hang in there.

Thanks Marc and Jase for the tips. Going to copy and put that one into practice. :thumbsup:

Thanks Rich, yes the satisfaction is fairly nice being able to fix this issue myself. Funnily enough these mounts are pretty simple when you pull them apart. The design is of simplicity and that makes servicing easy. I'll get that RC going soon. Promise.:)

[Bassnut]

Most excellent Paul. Presented in a different format which puts it above the others weve seen lately.

[mill]

Very well done picture Paul :thumbsup:
Here is the easy way of getting rid of the reflections.
In Photoshop click the clone stamp tool and set it to 12 pixels with the hardness set to zero.
Then enlarge the picture to 200% and alt click on a neutral spot close to the object, then clone that over the halo.
I think you might already know about the clone tool or just didn't use it?

Here is the picture done with the clone tool.

[Paul Haese]

Thanks Fred, it sort of lends the idea to a mosaic down the track, perhaps. There seems to be some fainter dust worth imaging.

Hi Martin, yeah I tried the clone tool, but was not entire happy with the results. The hardness was not at that setting though. Also you can change the star field a little by doing this, and that just sort of eats at me personally. Generally a good tip Martin. :)

[Bassnut]

No Paul, mosiacs just mean wider feild, and thats never a good thing. Zoom in mate, thats where its at.

[Paul Haese]

Yeah Fred I get you. Closer is good too. :)

[Hagar]

Very nice Paul. I had to search hard for the second blue area you spoke of. You are a bit too critical of your own work, which by the way is excelent. Working with our equipment and an atmosphere above it is not out of the question to accept small aberations which are caused by equipment limitations.

One very quick and easy way to make the blue presentable is just select it with the round marque tool. Select it bigger than you really need, feather by something like 20 pixels, hide the selection edges (Makes it easier to see), open hue and saturation, select the collour you wish to remove with the eye dropper. (In this case I would select blue first then the eyedropper select), Using the saturation slider just desaturate the blue and maybe cyan till the aberation disappears. This will usually leave the base colours pretty right and with the 20 pixel feather it should all blend in nicely.

Have fun with it Mate and don't worry too much.

[Paul Haese]

Thanks Doug, another technique to try. You are right, I have high expectations of my own imaging. Always striving for better. :)

[marc4darkskies]

Ah yes! Very nice Paul!

Cheers, Marcus

[h0ughy]

i wasn't expecting suck a bright blue but it look nice - an inviting image to delve into - lovely

[DavidU]

I would be proud of that Paul, great effort !

[Ross G]

Amazing photo Paul.

Great colours and detail.


Thanks.

Ross.

[strongmanmike]

Very nice work on a favourite :thumbsup:

All looks pretty good to me and the portrait framing is a nice change.

The reflections are insignificant

Mike

[gregbradley]

Thats a lovely image Paul. You really captured the dust well and its a nice colour shade (well of dust). What I mean is dust can sometimes look magenta-ish.

Great star colours and a wide enough FOV to capture the area nicely.

Another few approaches to the good tips on the reflections:

1. Healing tool set to color blend mode instead of normal. This then corrects for unusual colours and leaves details alone. Same with clone tool.

2. Sponge set to desaturate and set it to 5% and rub it on the offending areas.

3. Marquee lassoo tool , hold down shift key and drag it to the right size.
Drag it over the area affected, feather it, then use selective colour to reduce the blue and balance the resulting change or you can use saturation tool and select blues and reduce the saturation or shift the hue. A few ways of approaching this.

Sponge tool or healing tool set to colour is what I would normally use, fast and easy.

Greg.

[Paul Haese]

Thanks Greg. I will now have go off and see which one I like best or which ones will work best for me.

Thanks all for the advice.

[SkyViking]

That's an amazing image Paul. The composition is great and the colours very balanced and smooth. It looks very intriguing. Excellent processing too and again it's great to see such top images coming from the QSI. I can't wait to get my own :)

I noticed there are some black 'double dots' in a few places, just wondering what they were? I have highlighted them on the attachment.

[Paul Haese]

Thanks for highlighting those Rolf. Those look like hot pixels that got missed. I think my luminence darks need doing again. It has been over 6 months and the errant pixels are starting to show again. I recently did the coloured ones again but thought the Lum dark was ok. Clearly not.

[Tom Davis]

Very, very nice!

Tom

[multiweb]

CCDStack -> Reject Range <0 >-100000 -> Interpolate rejected pixels 1px 3 iterations. Gone :)

[John Hothersall]

Gosh that is an amazing area of sky like rho Oph especially with the big glob. Lovely image

[Paul Haese]

Thanks guys.

Marc, thanks will give that a try too. Pesky hot pixels.

[Paul Haese]

Sorry cannot find reject range? Which menu is that located?

[Paul Haese]

Ah don't worry I found it.

edit wrong again. found reject range indata reject but cannot find interpolate rejected pixels. Maybe on another edition of CCDstack?

[Paul Haese]

Marc I found the reject range, but could not find how to interpolate rejected pixels? Could you explain?

[wysiwyg]

Select "Impute Rejected Pixels" from the drop down list.

[ving]

great shooting paul. :D

[Paul Haese]

That does not seem to work Mark. the black pixels are still there.

I first did the reject range as suggested. The I next go to impute rejected pixels and apply. Then I close that and the pixels are still there. What am I doing wrong?

[wysiwyg]

Paul,

I'm not sure if they are hot pixels or not, cold I would say as they are black.
I had this problem with my STL, and it came down to the fact that I was using old dark frames.
Dark frames need to be updated regularly as the characteristics of the chip change over time, same with flat libraries.

It solved the problem for me.
In the mean time just remove them in PS, there aren't that many.

Cheers
Mark

[Paul Haese]

Yeah I think you're right Mark. I have just done a new battery of darks this last week. I suspect these are from my luminence darks which I only redid two nights ago after imaging until 4 am. I have not seen any pixels like this in the newer work I am processing. So I will undergo another reprocess and see if I can eliminate them.

[gregbradley]

CCDs deteriorate over time. They get radiation damage.

My 16803 developed a vertical line which many have when you get them but mine had none.

This is usual. Darks need to be updated from time to time. That reminds me to update mine.

Greg.

[TheDecepticon]

That is a very lovely image, Paul! :thumbsup:

Great colour in the dust lane and the reflection nebulosity, with the globular resolved very well.:eyepop:

[Paul Haese]

Thank Grey. I really like the globe but wish I had turned the camera 90 degrees before I started the image.

Was good to catch up last night. Next time when I get together with Jim you should come along too.

[Stevec35]

Nicely done Paul. Everything looks pretty good to me.

Cheers

Steve