Amazing Saturn optics

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adi11235
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Amazing Saturn optics

Post #1by adi11235 » 09.01.2007, 09:22

This is a fantastic picture of Saturn eclipsing the Sun:

Image

Is it possible to incorporate these effects into Clestia?

The rings are partially transparent, they also reflect some sunlight onto the dark side of the planet and they glow when lit.

It would also be cool to have the halo and other optical effects of eclipses, but not limited to Saturn.

bh
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Post #2by bh » 09.01.2007, 09:28

No.
regards...bh.

Topic author
adi11235
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Post #3by adi11235 » 09.01.2007, 09:41

Hm... Would it be possible to change textures dynamically based on events? (such as, if the planet obscures the Sun)

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t00fri
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Re: Amazing Saturn optics

Post #4by t00fri » 09.01.2007, 10:54

adi11235 wrote:Is it possible to incorporate these effects into Celestia?

The rings are partially transparent, they also reflect some sunlight onto the dark side of the planet and they glow when lit.

It would also be cool to have the halo and other optical effects of eclipses, but not limited to Saturn.


Qualitatively, a number of visible optical effects will be rendered with Celestia 1.5.0, which sports the new Mie atmosphere code.

So the Saturn atmosphere may be adjusted to show the apparent backscattering of light around it's periphery in the above Saturn image. That's an easy exercise, just like I demonstrated it for Titan earlier.

The code already implements all effects of "geometrical optics", like ring illumination and ring shadows under the present conditions.

I should also remind people that in the default Celestia ring texture we have since a long time implemented existing scientific hires data about the ring /transparency/. These data were obtained from earthbound measurements of the amount of light penetrating the rings during the ring crossing of a star. This information is /independent/ from albedo data that were implemented from the results of the Cassini mission.
The hires transparency data are in the alpha channel of the default ring texture, while the albedo makes up the RGB channels. In order to be able to obtain a realistic rendering of the rings in varying light conditions, one NEEDS to know these two independent input quantities, transparency and reflectivity (albedo), across the rings.

Celestia's rendering so far assumes mainly that we observe in a wavelength and sensitivity window corresponding to naked eye vision. Hence the newly discovered outer rings are NOT part of Celestia's rendering task. Don't forget that these photographic images underwent a large amount of image processing! This we do not implement into Celestia as a matter of consistency.

Bye Fridger
Image


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