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Comet processing... Is this cheating?

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#1 bobFranke



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Posted 31 May 2020 - 03:58 AM

Hello everyone,


Processing comet "pretty pictures" is always difficult. I have developed a way to remove the stars from the comet aligned image. However, I still find it very difficult to remove the comet from the star aligned image. I always find it tempting to just shoot the star field the next night.


So, is this cheating?




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#2 sydney


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Posted 31 May 2020 - 05:04 AM



I’ve also considered that approach for pretty comet pictures.  I don’t think it is cheating on a substantive level, but probably should be disclosed for transparency. There may be awkward questions to answer if something unexpected reveals the “composite”.  I believe DSS has a feature that aligns and stacks comet images twice, once on the stars and the other on the comet, and then combines them to eliminate the trailing.

#3 Paul Garais

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Posted 31 May 2020 - 05:43 AM

In my opinion, the intended use of the image decides, what is cheating and what is not. "Pretty pictures" are exactly that. They are pretty. The goal is not scientific accuracy.

If you are taking images as documentation or for scientific reasons, accuracy is key. Altering reality would be a problem. Let's say you take an image of a comet and combine it with the starfield imaged a few nights later. Things could have changed in between and you could get a wrong assumption about asteroids, supernovae, and other objects, that can change within days.

For me, pretty pictures are a form of art. And art has no need for rules. How do you let other people experience, what you felt while watching or imagining a comet? Scientific accuracy won't be the no. 1 tool to achieve this.


#4 vakulenko_sergiy


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Posted 31 May 2020 - 08:07 AM

There is no cheating until you clearly state how final image is obtained. Sometimes I see in social media jaw-dropping images of comets near faint DSOs. But I have feeling that those images are combination of nebula and comet shot separately. It bothers me when it is not indicated directly.

#5 Dan Crowson

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Posted 31 May 2020 - 04:26 PM

I'd be on the side of not cheating. All the comet images with a static comet and stars are pretty much composites anyway. For 'scientific' results, just a stack on the comet would be good.


#6 Alex McConahay

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Posted 31 May 2020 - 05:03 PM

>>>>>So, is this cheating?


How can you cheat if there are no rules?


And, tune in to The Astro Imaging Channel tonight (Sunday, May 31, 9:30 Eastern). Bob Traube will show you how to process comets in PixInsight.




If you use only DSS/Photoshop, try a recent TAIC show with Brian Clemens: 





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#7 spokeshave



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Posted 01 June 2020 - 08:43 AM

>>>>>So, is this cheating?
How can you cheat if there are no rules?

Exactly - except that I think there is one, and only one, rule: Do not pass off the work of others as your own.

Other than that one rule, have fun and do whatever tickles your fancy. Keep in mind that other astrophotographers are often interested in how an image was acquired and processed, so it is usually good form when publishing an image to say what you did, particularly if you used any unique or unusual techniques.



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