Bjoern Jaeger wrote:

> Do you also have the problem with the clouds getting black in the distance ?

This sounds like the classical max_trace_level problem. Just increase it to 500
or whatever - that should remove the artifacts you're experiencing. (Look it up
in the docs for more info)

- Mikael.

----------------------------------------------------
Mikael Carneholm
Dep. of Computer Science and Business Administration


Personal home page:
http://www.studenter.hb.se/~arch
E-mail:
sa9### [at] idautbhbse

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In article <388A453B.C0CDC4E7@ida.utb.hb.se>, sa9### [at] idautbhbse 
wrote:

> Bjoern Jaeger wrote:
> 
> > Do you also have the problem with the clouds getting black in the 
> > distance ?
> 
> This sounds like the classical max_trace_level problem. Just increase it 
> to 500
> or whatever - that should remove the artifacts you're experiencing. (Look 
> it up
> in the docs for more info)

It isn't...it happens because the samples get spread out more and more 
as they get farther and the angle they intersect the cloud box 
increases. This can be fixed by making transparent vertical partitions 
to force more intervals to be made. Of course, this also means you may 
have to increase max_trace_level to get the ray past the partitions.

There is also a patch to fix the problem, which gives a keyword to 
control the distance allowed between samples(or was it the maximum 
distance before a new interval was started?), but I can't find anything 
in the MegaPOV docs about it so it may not be included. I think it was 
something like max_distance or max_interval_length. There were some 
posts about it a while back, about the same subject(media clouds), and 
it was created to solve the problem with media clouds. Sorry I don't 
have more info on it...

-- 
Chris Huff
e-mail: chr### [at] yahoocom
Web page: http://chrishuff.dhs.org/

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This is a very nice image! The clouds are great and like everyone else
I'd love to see a larger version, source and statistics.
As Bob pointed out the sky is a bit dark but perhaps it's a gamma thing.
Also there have been some efforts to make a convincing sun lately and
yours is one of the better ones I've seen.
Nice work!
-- 
Phil
...coffee?...yes please! extra sugar,extra cream...Thank you.

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HEY!!! I've warned you people about posting photographs to this newsgroup!!!
Don't make me get nasty!!!

(IOW... WOW!!!)

Eric
---------------
"A wise and frugal government, which shall restrain men from injuring one
another, which shall leave them otherwise free to regulate their own
pursuits of industry and improvement, and shall not take from the mouth of
labor the bread it has earned.  This is the sum of good government."
     - Thomas Jefferson
     - First inaugural address, 1801
---------------
http://www.ametro.net/~ericfree

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Greetings,

Thank you all for your response - I did not quite expect that much
appreciation!

I'm going to take a bit of a liberty here and post a general reply
without following any particular threads. Hope this does not offend any
one. Here goes...

- The source, for those interested is posted in p.b.s-f

- Render times for a 512x384 frame was about 9.5 hrs (no AA) on a 90MHz
pentium w/ 24 megs of memory. I posted a reduced version because I did
not feel at the time that the larger file size was warranted.

- I'm still trying to render a larger 640x480 version, but its taking a
while. If anyone with more CPU time and speed would like to do one with
higher quality settings, feel free!

- Some of you mentioned that the color was a bit off towards the reddish
side (esp in the blue). I've noticed this too when I view my pics on
some other monitors, particularly with Macs.

  I'd also like to make a few general comments about this scene. While
it would be nice, to see it larger, this particular scene as it stands
has an effective size limit of about 640x480. Beyond that I would expect
the cloud details to become chunky, and the terrain texture too "plain"
(eg. no grass blades or rocks where one would start to expect to see
them). This is simply because I did not intend to render it at higher
resolutions. However, there are probably a few simple things that could
be adjusted to compensate, namely a higher octave value in the cloud
turbulence and/or increasing the camera angle for larger renders.
  Regarding the media, the sampling parameters are just borderline and
could be adjusted for better quality on the clouds, given that longer
render times are acceptable.

  Thank you again for your replies!

Abe

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I have started a 1024x576,AA 0.3 render on my 
PII 400 w. 128M Ram machine. 48% done in 2h20m.

I left all settings as were as I don't know
what I am doing with the setup that you used.

The clouds still look good, but I cant see the
ground jet so who knows.

Abe wrote:
> 
> Greetings,
 
> - I'm still trying to render a larger 640x480 version, but its taking a
> while. If anyone with more CPU time and speed would like to do one with
> higher quality settings, feel free!
> 

-- 
Mr. Art

"Often the appearance of reality is more important 
than the reality of the appearance."
Bill DeWitt 2000

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regaurding the "grape" color of the sky, I have seen this color before, and
I think it fits wonderfully in this image. It looks like  heavy thunderstorm
is about to move in from the far right.

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Yes, make it bigger!! BIGGER! BIGGER! Wallpaper-Size!!

Andreas
http://www.anna-fans.com

Ken wrote:

> Abe wrote:
> >
> > Greetings,
> >
> > Another landscape. Clouds are scattering media type 3 used in MegaPOV
> > (if you're reading this Nathan, thanks much for your media work!).
> > Terrain was generated in HF-lab. Since I am working from an LCD monitor,
> > the colors may be a bit off. Post processing note: this image here was
> > reduced about 75% from the original render.
> >
> > Any comments appreciated, esp. in regards to atmos/cloud color, contrast
> > and gamma (again my monitor).
> >
> > Abe
>
> If this is really the output from POV-Ray I can only say
> "Look out Terragen !!!". This image is fantastic. I would
> really like to see a higher resolution image of this and
> the source if at all possible. Render stats would also
> be appreciated.
>
> On my system your output is right on the money and I wouldn't
> change a thing were I you.
>
> WoW !
>
> Wee !
>
> --
> Ken Tyler -  1300+ Povray, Graphics, 3D Rendering, and Raytracing Links:
> http://home.pacbell.net/tylereng/index.html http://www.povray.org/links/

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WoW And WoW Again... I too tend to feel that the sky color and atmosphere fit
quite well in this scene... on my mac...  it looks great... excellent work...
would love you to post more...

Ross Litscher wrote:

> regaurding the "grape" color of the sky, I have seen this color before, and
> I think it fits wonderfully in this image. It looks like  heavy thunderstorm
> is about to move in from the far right.

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3h 54m

"mr.art" wrote:
> 
> I have started a 1024x576,AA 0.3 render on my
> PII 400 w. 128M Ram machine. 48% done in 2h20m.
> 
> I left all settings as were as I don't know
> what I am doing with the setup that you used.
> 
> The clouds still look good, but I cant see the
> ground jet so who knows.
> 


-- 
Mr. Art

"Often the appearance of reality is more important 
than the reality of the appearance."
Bill DeWitt 2000

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