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steveward53
Carpal Tunnel


Reged: 05/14/12

Loc: Newmarket,UK
Sun in whitelight 9th January 2013 , 10:30 GMT
      #5613282 - 01/09/13 08:30 AM

Back at it again after what seems like an eternity . . .

45 frames stacked in poor seeing.

Couldn't get rid of a strange effect on the edge , looks like a stacking problem but the features all line up OK ?



1000D + ST120 + ND3.8 + 1.8 x Barlow + UHC + S/L.
1/1250s @ ISO 100 , 45/45 , Reg 5.1 , Gimp2.8.

Day by day album . . . http://www.astrobin.com/users/steveward53/


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Andrev
Post Laureate
*****

Reged: 02/08/11

Loc: Montreal, Quebec, Canada
Re: Sun in whitelight 9th January 2013 , 10:30 GMT new [Re: steveward53]
      #5613881 - 01/09/13 03:01 PM

Wow, these new spots are quite amazing. Very beautiful image.

Andre


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BYoesle
Post Laureate
*****

Reged: 06/12/04

Loc: Goldendale, Washington USA
Re: Sun in whitelight 9th January 2013 , 10:30 GMT new [Re: Andrev]
      #5613946 - 01/09/13 03:42 PM

Very nice image Steve!

You might be seeing more of a sharpening effect on the edge such as "ringing." I often see this with unsharp masking. Sometimes adding some "clipping" or adding a little gaussian blurring will help.


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steveward53
Carpal Tunnel


Reged: 05/14/12

Loc: Newmarket,UK
Re: Sun in whitelight 9th January 2013 , 10:30 GMT new [Re: BYoesle]
      #5614136 - 01/09/13 05:33 PM

Cheers Bob ,

I had a funny thin halo on the subs that I'm sure was an atmospheric thing , the seeing was poor and the disc appeared to be 'flexing' and had a very rough edge.

Crop from single sub.




Having had a play I can reduce it somewhat by moving the blackpoint on the subs so I will probably just select the very best subs tomorrow , adjust and restack to see if I can improve this one .

going to be cloudy again so need something to do . . .

Steve.


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raylal
Carpal Tunnel


Reged: 04/19/10

Loc: Cornwall, Ont., Canada
Re: Sun in whitelight 9th January 2013 , 10:30 GMT new [Re: steveward53]
      #5616161 - 01/10/13 07:50 PM

I find that full disk shot is phenominal, so nice to see so much activity on the surface. Great job Steve.

Ray


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tomnjulie
member


Reged: 12/04/12

Loc: Texas
Re: Sun in whitelight 9th January 2013 , 10:30 GMT new [Re: raylal]
      #5622047 - 01/14/13 01:50 AM

What program did you use to stack these?

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steveward53
Carpal Tunnel


Reged: 05/14/12

Loc: Newmarket,UK
Re: Sun in whitelight 9th January 2013 , 10:30 GMT new [Re: tomnjulie]
      #5622147 - 01/14/13 05:35 AM

Reg 5.1 . . .

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BYoesle
Post Laureate
*****

Reged: 06/12/04

Loc: Goldendale, Washington USA
Re: Sun in whitelight 9th January 2013 , 10:30 GMT new [Re: steveward53]
      #5624687 - 01/15/13 03:50 PM Attachment (7 downloads)

Hi Steve,

I was thinking about this and went back to review the processing of one of my better white light images taken last April. The seeing was excellent (at least for me), so I don’t think that’s the origin - at least of the bright ring aspect of the effect. I too use RegiStax – version 6.

Here’s my original (reduced size) full disc mosaic, showing the “edge effect:” I appear to use a little less contrast enhancement and final sharpening than your image:


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BYoesle
Post Laureate
*****

Reged: 06/12/04

Loc: Goldendale, Washington USA
Re: Sun in whitelight 9th January 2013 , 10:30 GMT new [Re: BYoesle]
      #5624689 - 01/15/13 03:51 PM Attachment (6 downloads)

Here’s a raw single frame:

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BYoesle
Post Laureate
*****

Reged: 06/12/04

Loc: Goldendale, Washington USA
Re: Sun in whitelight 9th January 2013 , 10:30 GMT new [Re: BYoesle]
      #5624691 - 01/15/13 03:51 PM Attachment (7 downloads)

Here’s an align and stack of the 30 best frames:

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BYoesle
Post Laureate
*****

Reged: 06/12/04

Loc: Goldendale, Washington USA
Re: Sun in whitelight 9th January 2013 , 10:30 GMT new [Re: BYoesle]
      #5624692 - 01/15/13 03:52 PM Attachment (7 downloads)

Here’s the wavelet sharpened image, which shows the origin the bright ring of the “edge effect:”

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BYoesle
Post Laureate
*****

Reged: 06/12/04

Loc: Goldendale, Washington USA
Re: Sun in whitelight 9th January 2013 , 10:30 GMT new [Re: BYoesle]
      #5624726 - 01/15/13 04:11 PM Attachment (6 downloads)

So a full disk (reduced to fit the posting requirements) with additional sharpening and some brightness and contrast adjustment. Thus it seems it’s the wavelet sharpening generating the bright ring of the edge effect. I do show a bit of ege darkening as well, but the more visible band of inner darkening of your image may be (at least partly) due to poorer seeing:

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steveward53
Carpal Tunnel


Reged: 05/14/12

Loc: Newmarket,UK
Re: Sun in whitelight 9th January 2013 , 10:30 GMT new [Re: BYoesle]
      #5624948 - 01/15/13 06:41 PM

Hi Bob ,
The effect was showing on my stacks pre-wavelet , and gone today . . . I can only put it down to the seeing . . !

Steve.


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