Uneven Diffraction Spikes on Red Channel [Deep Sky] Processing techniques · Alien_Enthusiast · ... · 7 · 239 · 2

Alien_Enthusiast 2.86
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Good evening AstroBinners! 

Im here with yet another dillema.

For some reason, on my red channel, 95% of the frames have sideways diffraction spikes, in addition to the standart X shape. However all the other channels, including Luminance, green and blue, do not have the small sideway spikes, showcasing only the classic X diffration.

What might be the reason for that?

I though the problem was in the reference frame, but I manually went thru all of them, and in red folder almost every frame (90%+) seems to contain those sideways spikes.

What might be the reason for that? Is this normal? What should I do?

Thank you all in advance!



Red Channel:
image.png


Luminance Channel:
image.png
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WhooptieDo 10.40
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Spikes will always be an indication of something obstructing your light path.   The challenge often times is finding why. 

Possible scenarios:   

Focuser drawtube moved just a slight bit inside the OTA when red was focused, obstructing the edge of the light path.
A cord came lose and hung in front of your scope aperture.
A large bug landed somewhere on your scope.
Your dew shield came lose mid session and no longer has a perfectly round aperture.
Aliens.

The possibilities are endless….   but it's always going to be some sort of obstruction.  That's the nature of telescopes.
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Alien_Enthusiast 2.86
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Brian Puhl:
Spikes will always be an indication of something obstructing your light path.   The challenge often times is finding why. 

Possible scenarios:   

Focuser drawtube moved just a slight bit inside the OTA when red was focused, obstructing the edge of the light path.
A cord came lose and hung in front of your scope aperture.
A large bug landed somewhere on your scope.
Your dew shield came lose mid session and no longer has a perfectly round aperture.
Aliens.

The possibilities are endless....   but it's always going to be some sort of obstruction.  That's the nature of telescopes.

How critical do you think it is for the overall image? Is there point in trying to battle those sideways spikes or just let it be?
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WhooptieDo 10.40
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Alien_Enthusiast:
Brian Puhl:
Spikes will always be an indication of something obstructing your light path.   The challenge often times is finding why. 

Possible scenarios:   

Focuser drawtube moved just a slight bit inside the OTA when red was focused, obstructing the edge of the light path.
A cord came lose and hung in front of your scope aperture.
A large bug landed somewhere on your scope.
Your dew shield came lose mid session and no longer has a perfectly round aperture.
Aliens.

The possibilities are endless....   but it's always going to be some sort of obstruction.  That's the nature of telescopes.

How critical do you think it is for the overall image? Is there point in trying to battle those sideways spikes or just let it be?



Just depends on how you process it.   Personally, I'd process the image normally, see how it looks in the end.  If it bothers me enough, just fix the issue and come back another night, shoot an hour of red without the spikes and recombine simply for the stars.       Frankly, I have little spikes that pop up on my frac every once in awhile, they're from things like spiders, or hairs stuck somewhere in the system.   I leave them... doesn't bother me at all.
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Alien_Enthusiast 2.86
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Brian Puhl:
Alien_Enthusiast:
Brian Puhl:
Spikes will always be an indication of something obstructing your light path.   The challenge often times is finding why. 

Possible scenarios:   

Focuser drawtube moved just a slight bit inside the OTA when red was focused, obstructing the edge of the light path.
A cord came lose and hung in front of your scope aperture.
A large bug landed somewhere on your scope.
Your dew shield came lose mid session and no longer has a perfectly round aperture.
Aliens.

The possibilities are endless....   but it's always going to be some sort of obstruction.  That's the nature of telescopes.

How critical do you think it is for the overall image? Is there point in trying to battle those sideways spikes or just let it be?



Just depends on how you process it.   Personally, I'd process the image normally, see how it looks in the end.  If it bothers me enough, just fix the issue and come back another night, shoot an hour of red without the spikes and recombine simply for the stars.       Frankly, I have little spikes that pop up on my frac every once in awhile, they're from things like spiders, or hairs stuck somewhere in the system.   I leave them... doesn't bother me at all.

For the future generations: I actually managed to solve it. Simply do all the processing, and then use GIMP "healing tool" to select similar area of the star to fix the diffraction spike. Works great, Ill post my final image when its ready.
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WhooptieDo 10.40
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wait, was it just one or two stars? or all of them?   I might have missed that part.
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Alien_Enthusiast 2.86
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Brian Puhl:
wait, was it just one or two stars? or all of them?   I might have missed that part.

Just one star. Wait I see where you are coming from... Thats wierd... if it was a bug every star would be like that. Idk maybe aliens are buidling Dyson sphere around it 
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WhooptieDo 10.40
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Alien_Enthusiast:
Brian Puhl:
wait, was it just one or two stars? or all of them?   I might have missed that part.

Just one star. Wait I see where you are coming from... Thats wierd... if it was a bug every star would be like that. Idk maybe aliens are buidling Dyson sphere around it 



Haha.  Okay I was under the assumption it was all the stars in that channel.   If that's the case it's gonna be just a hair or speck on either your secondary, or maybe even primary.
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