#1  
Old 22-09-2020, 10:41 AM
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PKay (Peter)
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Explain this please!

Here are two images.
At first I thought the artefact beside Alnitak was caused by a rain drop on the primary.

If that was the case, when I slewed the target, the artefact would have stayed in the same place.
However, it has moved with the star!
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  #2  
Old 22-09-2020, 10:49 AM
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RB (Andrew)
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Internal reflection caused by the brightness of Alnitak.
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  #3  
Old 22-09-2020, 11:01 AM
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multiweb (Marc)
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Quote:
Originally Posted by RB View Post
Internal reflection caused by the brightness of Alnitak.
That's not a reflection. That's a reflection
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  #4  
Old 22-09-2020, 11:07 AM
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Quote:
Originally Posted by RB View Post
Internal reflection caused by the brightness of Alnitak.
This^

See how it shifted closer to Alnitak in the second image when Alnitak was moved closer to the centre of the image.
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  #5  
Old 22-09-2020, 11:10 AM
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Atmos (Colin)
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https://www.astrobin.com/full/npr2g6/0/

BIG reflection!
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  #6  
Old 22-09-2020, 11:16 AM
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How disappointing.

I spent half an hour cleaning the lens :-)

Not to mention it not being a new star appearing out of thin air...

Can I get rid of it?
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  #7  
Old 22-09-2020, 11:24 AM
glend (Glen)
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Whenever I Image the Horsehead I always frame it so Alnitak is out of the shot, it causes too many issues.
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  #8  
Old 22-09-2020, 11:28 AM
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RB (Andrew)
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Originally Posted by PKay View Post
How disappointing.

Can I get rid of it?
Alnitak?
Not unless you're God.

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  #9  
Old 22-09-2020, 11:31 AM
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That's not a reflection. That's a reflection
I kinda like it.
Your own private unicorn.
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  #10  
Old 22-09-2020, 11:38 AM
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Avoid imaging in the rain.
Alex
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  #11  
Old 22-09-2020, 12:43 PM
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Quote:
Originally Posted by PKay View Post
How disappointing.

I spent half an hour cleaning the lens :-)

Not to mention it not being a new star appearing out of thin air...

Can I get rid of it?
Offsetting the fov, dithering and a meridian flip.
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  #12  
Old 22-09-2020, 01:14 PM
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Quote:
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Alnitak?
Not unless you're God.

:rofl :

hahah love it.

could definitely have a reflection-off competition... we've all been there at some stage - trying to deal with pesky Alnitak.

but yes - some aggressive dithering or even a combo of dithering and alternate framing merged via intersection method.
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  #13  
Old 22-09-2020, 01:33 PM
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Found a solution...

(& thnx Jeff)
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  #14  
Old 22-09-2020, 02:32 PM
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Found a solution...

(& thnx Jeff)
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  #15  
Old 22-09-2020, 03:03 PM
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If you spend a little time in PS you can get rid of it. Zipped the file for you. You can do a better job but you get the idea.
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  #16  
Old 22-09-2020, 05:23 PM
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That's not a reflection. That's a reflection
Thatís a damned Klingon phaser blast...
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  #17  
Old 23-09-2020, 02:07 PM
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Alnitak?
Not unless you're God.




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  #18  
Old 23-09-2020, 02:08 PM
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Avoid imaging in the rain.
Alex
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