POV-Ray : Newsgroups : povray.binaries.images : more sunset clouds (~55 Kb) Server Time
3 Nov 2024 16:04:07 EST (-0500)
  more sunset clouds (~55 Kb) (Message 1 to 10 of 10)  
From: Abe
Subject: more sunset clouds (~55 Kb)
Date: 5 Jun 2000 20:18:41
Message: <393C42CE.64DEF879@taconic.net>
This is an experiment in under-cloud illumination (as by sunset/rise).
It is hardly a good model in that the sky glow is not a function of sun
altitude and the sun itself is not a visible object. Probably just
better to consider it low-angle-of-incidence-media-illumination.

Anyway, I'm looking for some feedback on cloud illumination realism
here. The sun is below the horizon (I think!) and slightly to the left
of center. Please ignore the cheesy horizon.

Abe


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Attachments:
Download 'evening_clouds.jpg' (59 KB)

Preview of image 'evening_clouds.jpg'
evening_clouds.jpg


 

From: DougE
Subject: Re: more sunset clouds (~55 Kb)
Date: 5 Jun 2000 20:25:13
Message: <393c44e9@news.povray.org>
This looks very nice.  One of the things I've noticed when looking at clouds
(and thinking about rendering them) is the border... the edges of a cloud
appear to be either lighter or darker than the center, kind of like a halo
effect.
Just a thought.

-Doug Eichenberg


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From: Tony[B]
Subject: Re: more sunset clouds (~55 Kb)
Date: 5 Jun 2000 20:44:00
Message: <393c4950@news.povray.org>
Nice.


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From: Bob Hughes
Subject: Re: more sunset clouds (~55 Kb)
Date: 5 Jun 2000 22:18:55
Message: <393c5f8f@news.povray.org>
"DougE" <dou### [at] nlsnet> wrote in message news:393c44e9@news.povray.org...
| One of the things I've noticed when looking at clouds
| (and thinking about rendering them) is the border... the edges of a cloud
| appear to be either lighter or darker than the center, kind of like a halo
| effect.

Yes, except in this case there are probably supposed to be shadows cast
perhaps even on the edges from other clouds between them and the sun.  Never
easy to discern about such amorphous objects as clouds to begin with.
About observations, I would think this particular set of clouds might be best
set into a more misty atmosphere to do it justice.  Just my opinion of course.

Bob


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From: SamuelT
Subject: Re: more sunset clouds (~55 Kb)
Date: 5 Jun 2000 22:27:56
Message: <393C6245.EBEA80F0@aol.com>
Could use some ground fog to soften the horizon and maybe use angle-dependent
reflection for the water. At any rate, the sky's color is good and those
clouds are *very* close to looking real.

Abe wrote:

> This is an experiment in under-cloud illumination (as by sunset/rise).
> It is hardly a good model in that the sky glow is not a function of sun
> altitude and the sun itself is not a visible object. Probably just
> better to consider it low-angle-of-incidence-media-illumination.
>
> Anyway, I'm looking for some feedback on cloud illumination realism
> here. The sun is below the horizon (I think!) and slightly to the left
> of center. Please ignore the cheesy horizon.
>
> Abe
>
>   ------------------------------------------------------------------------
>  [Image]

--
Samuel Benge

E-Mail: STB### [at] aolcom

Visit my isosurface tutorial at http://members.aol.com/stbenge


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From: Christoph Hormann
Subject: Re: more sunset clouds (~55 Kb)
Date: 6 Jun 2000 04:36:20
Message: <393CB803.353BC955@gmx.de>
quite good!

a larger version would help, the gap above the horizon does not look
good, I do not totally understand how you did that, but it looks like a
planar structure that ends in the distance.  Maybe you shold try a
spherical shape.  

By the way, what's the render time ?

Christoph

--
Christoph Hormann <chr### [at] gmxde>
Homepage: http://www.schunter.etc.tu-bs.de/~chris/


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From: Tony Micklus
Subject: Re: more sunset clouds (~55 Kb)
Date: 6 Jun 2000 09:25:27
Message: <393cfbc7@news.povray.org>
The size of the picture makes it difficult to see imperfections. I think
your clouds look incredibly real!

>Anyway, I'm looking for some feedback on cloud illumination realism
>here. The sun is below the horizon (I think!) and slightly to the left
>of center. Please ignore the cheesy horizon.
>
>Abe


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From: ryan constantine
Subject: Re: more sunset clouds (~55 Kb)
Date: 6 Jun 2000 14:53:59
Message: <393D49C3.FA39B87D@yahoo.com>
if anyone has gone outside on a cloudy day, they may have noticed that
clouds don't always go to the horizon.  they go here and there and in
any shape or coverage they please.  i believe abe puts the clouds in
boxes which lets him have any kind of cloud cover he wants.  he could
also probably put them in a csg difference of two spheres for them to go
to the horizon.

Christoph Hormann wrote:
> 
> quite good!
> 
> a larger version would help, the gap above the horizon does not look
> good, I do not totally understand how you did that, but it looks like a
> planar structure that ends in the distance.  Maybe you shold try a
> spherical shape.
> 
> By the way, what's the render time ?
> 
> Christoph
> 
> --
> Christoph Hormann <chr### [at] gmxde>
> Homepage: http://www.schunter.etc.tu-bs.de/~chris/


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From: Abe
Subject: Re: more sunset clouds (~55 Kb)
Date: 6 Jun 2000 17:16:44
Message: <393D69CD.CF94E6A3@taconic.net>
Render time on this was approx. 3 hr on a 90 MHz pentium. This is based
largly on choosing a high sample value which looked good, but without
putting any effort in trying to find an minimum which still gave good
results.

I kept the clouds contained by a spherical pattern to prevent them from
going to the horizon. It would be an improvement to break the hard edge
imposed by the pattern boundary.

Abe

Christoph Hormann wrote:
> 
> quite good!
> 
> a larger version would help, the gap above the horizon does not look
> good, I do not totally understand how you did that, but it looks like a
> planar structure that ends in the distance.  Maybe you shold try a
> spherical shape.
> 
> By the way, what's the render time ?
> 
> Christoph
> 
> --
> Christoph Hormann <chr### [at] gmxde>
> Homepage: http://www.schunter.etc.tu-bs.de/~chris/


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From: Vahur Krouverk
Subject: Re: more sunset clouds (~55 Kb)
Date: 9 Jun 2000 02:51:26
Message: <39409482.DE0A94C5@aetec.ee>
Abe wrote:
> 
> This is an experiment in under-cloud illumination (as by sunset/rise).
> It is hardly a good model in that the sky glow is not a function of sun
> altitude and the sun itself is not a visible object. Probably just
> better to consider it low-angle-of-incidence-media-illumination.
> 
> Anyway, I'm looking for some feedback on cloud illumination realism
> here. The sun is below the horizon (I think!) and slightly to the left
> of center. Please ignore the cheesy horizon.
> 
> Abe
> 
Clouds are nice. But shouldn't sunset have much more red(dish?)
appearance, than in this picture? At least here it has...


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