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A peculiar galaxy in the southern sky - Centaurus A ( NGC 5128 )


MikeODay

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4 hours ago, mike005 said:

As rarely as I can get away with.  I check it every time but I have only had to adjust it may be once every three times I use the scope.  Mind you, that has been around once every few months given the almost nightly clouds that have formed over the Blue Mountains near Sydney for the past 6 months.  As it starts to get dryer now as we head towards winter, hopefully I will get to focus more :)

 

Really...Focus--right?  Not collimation.  

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Mike 

These are superb.  I like all of your versions.  If forced to choose, I would probably go (just) for the slightly less saturated wider field version shown in your post towards the end of page 1.  But all are (more than) stunning.  The blue star directly above the galaxy seems to have a slight double spike to it.  I don't see this in the other stars and I wonder why it is there and if it is 'fixable'.   

Congratulations.

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10 hours ago, gnomus said:

Mike 

These are superb.  I like all of your versions.  If forced to choose, I would probably go (just) for the slightly less saturated wider field version shown in your post towards the end of page 1.  But all are (more than) stunning.  The blue star directly above the galaxy seems to have a slight double spike to it.  I don't see this in the other stars and I wonder why it is there and if it is 'fixable'.   

Congratulations.

Thank you, that is very kind of you.  I still can not decide if I prefer the saturated or toned-down versions - my wife insists that the saturated one is best.  I planned today to go back and try a rotated version of the 100% crop to improve the composition - I think having the dust cloud aligned with the long axis of the image will be more pleasing.  Anyway, I think I might go for a middle ground in terms of saturation.

The star with the double spike is a close double 5.2" apart with both stars around mag +9 resulting in the nearly identical very close spikes.

IMG_0704.JPG.35b8ede9038ae773db3b99667bcb1c72.JPG

IMG_0686.JPG.263c506405610c57841ea9eb0634a074.JPG

( SkySafari )

 

Cheers

Mike

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7 hours ago, mike005 said:

...

The star with the double spike is a close double 5.2" apart with both stars around mag +9 resulting in the nearly identical very close spikes.

...

Ha ha.  There's me showing my ignorance again.

Steve

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On 07/05/2017 at 16:21, gnomus said:

Ha ha.  There's me showing my ignorance again.

Steve

Me as well - when I was looking at the subs as they were being taken,  that "elongated" star with the wierd spikes made me think the collimation was off.  I was worried until I looked it up using SkySafari :)

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Updated again - to try to bring out more faint detail ...

5917c35e84e2c_CentaurusA-NGC5128-rotated-stretched-compressed.thumb.jpg.efddc94e30de6eb2e71da175b33bd1bd.jpg

Centaurus A ( NGC 5128 ) - rotated and cropped ( North is up )

( please click / tap on image to see full size )

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Still playing with it - the moon has gone but now I'm clouded in :(

This one is an extreme stretch to try to bring out detail in the faint regions of the galaxy ( B&W because the colour version looks really horrible ).  Not particularly attractive but I thought it was interesting...

591fbfc36e83a_CentaurusA-NGC5128-extremestretch-compressed2.thumb.jpg.a5a154fb6c5c9a2586e604ac60b96127.jpg

Centaurus A ( NGC 5128 ) - extreme stretch 

 

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A quite stunning image.  So nice to read all the background data on the galaxy, your kit and the settings you used. Did you dither?    I think your scope fl should read 1200mm! :)

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16 hours ago, Ouroboros said:

A quite stunning image.  So nice to read all the background data on the galaxy, your kit and the settings you used. Did you dither?    I think your scope fl should read 1200mm! :)

Thank you Ouroboros.

No, no dithering.  But the 240 sec subs were captured in three sessions over three nights and the alignment between the three was off by quite a bit.  I suppose this is equivalent to a partial dither.

Well spotted on the focal length!

Cheers 

Mike

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