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Jupiter 11th September- Edge experiment - Trinidad

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#1 wargrafix

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Posted 21 September 2021 - 08:17 PM

I have data i am still processing. An experiment i started last year with middling success to handle the fact that the exposures either reveal the disk edge but wash out the details or show details and vanish the edge. I will present 2 images and I want you to tell me which one looks better.

 

Celestron 9.25

ASI224MC

Mars-M

3X teleconverter

 

1)gallery_218407_320_34668.jpg

 

2)

gallery_218407_320_73304.jpg


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#2 Borodog

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Posted 21 September 2021 - 08:24 PM

The first one. But the difference is extremely subtle. Honestly I don't think it matters.


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#3 Xeroid

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Posted 21 September 2021 - 08:52 PM

To my eyes, 2 appears to show finer details of the planet.

 

In ether case, well done!



#4 Ittaku

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Posted 21 September 2021 - 09:00 PM

A difference in processing can make a massive difference to the edge appearance too.



#5 Tulloch

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Posted 21 September 2021 - 09:31 PM

Here's what my edge brightening procedure in Photoshop was able to do on your first image (details here).

 

After edge brightening routine...

 

wargrafix gallery_218407_320_34668 bright edge.jpg

 

Difference as animated gif...

 

wargrafix gallery_218407_320_34668 bright edge_pipp.gif

 

I prefer the second version with the bright edges, but that's just me ...

 

Andrew


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#6 wargrafix

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Posted 21 September 2021 - 10:09 PM

That's some fantastic work, and I will have to look into it.


I tried for the first image an attempt of bracketing exposures. And then using winjupos to both derotate and combine the exposures

#7 wargrafix

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Posted 21 September 2021 - 10:10 PM

The second was just derotation of similar exposures.

#8 RedLionNJ

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Posted 21 September 2021 - 10:16 PM

I would expect the edges of a gas giant to be a little darker, a little hazier-looking. It's just not reflecting light in our direction to the same degree PLUS it's a gassy globe, not a solid. Limb-darkening is real and is to be expected.



#9 Tim J Fowler

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Posted 22 September 2021 - 08:45 AM

Another way to do it is make two copies of the image. One adjusted to highlight the limb, and one to highlight the inner surface of the planet. After that, using a clone brush and "paint" the highlighted limb around the highlighted surface image. Just adjust the opacity and hardness of the brush to your liking. This technique requires a bit more work, but I think it allows more control of what you do to any given area of an image. I did an extremely exaggerated example here just to give you an idea of this technique. But, I agree with Grant, that the edges are going to be darker, and I personally like it when it's presented that way. To me it gives dimension/shape to Jupiter. 

Tim

Attached Thumbnails

  • gallery_218407_320_34668 1small.jpg
  • highlightedsmall.jpg
  • Comparison Animation.gif



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