I am using an iMac DV with my display set to 1024x768 at millions of
colors. Normaly, my scenes look great (that is, on POV-Ray's end of things).
They uselly use a plane object for the ground. However, I have been tring a
box the put it in a small room. The gradiations on the wall look a bit
banded, and the antialiasing looks chopy. What should I do?

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In article <B5273F77.7BA%dav### [at] maccom> , David <dav### [at] maccom>
wrote:

>     I am using an iMac DV with my display set to 1024x768 at millions of
> colors. Normaly, my scenes look great (that is, on POV-Ray's end of things).
> They uselly use a plane object for the ground. However, I have been tring a
> box the put it in a small room. The gradiations on the wall look a bit
> banded, and the antialiasing looks chopy. What should I do?

For gradients between some colors the human eye can distinguish more shades
than current display technology (= true color color with 8 bits per color
component) can show.  However, POV-Ray can generate 16 bits per color
component PNG images, yet only very few programs support them, and as
hardware can't display the additional shades anyway, you will have to wait
until (if ever) such hardware is available, but then POV-Ray will already
support it!


     Thorsten


____________________________________________________
Thorsten Froehlich
e-mail: mac### [at] povrayorg

I am a member of the POV-Ray Team.
Visit POV-Ray on the web: http://mac.povray.org

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Normally, I can not see the bands. In this picture only, I can.
I can tell that there are less then 16 million colors on that wall.
It looks like 256!

> From: "Thorsten Froehlich" <tho### [at] trfde>
> Newsgroups: povray.macintosh
> Date: Sat, 22 Apr 2000 14:08:30 -0500
> Subject: Re: Bands in graditations
> 
> In article <B5273F77.7BA%dav### [at] maccom> , David <dav### [at] maccom>
> wrote:
> 
>> I am using an iMac DV with my display set to 1024x768 at millions of
>> colors. Normaly, my scenes look great (that is, on POV-Ray's end of things).
>> They uselly use a plane object for the ground. However, I have been tring a
>> box the put it in a small room. The gradiations on the wall look a bit
>> banded, and the antialiasing looks chopy. What should I do?
> 
> For gradients between some colors the human eye can distinguish more shades
> than current display technology (= true color color with 8 bits per color
> component) can show.  However, POV-Ray can generate 16 bits per color
> component PNG images, yet only very few programs support them, and as
> hardware can't display the additional shades anyway, you will have to wait
> until (if ever) such hardware is available, but then POV-Ray will already
> support it!
> 
> 
> Thorsten
> 
> 
> ____________________________________________________
> Thorsten Froehlich
> e-mail: mac### [at] povrayorg
> 
> I am a member of the POV-Ray Team.
> Visit POV-Ray on the web: http://mac.povray.org

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In article <B529041B.B39%dav### [at] maccom>, David 
<dav### [at] maccom> wrote:

> Normally, I can not see the bands. In this picture only, I can.
> I can tell that there are less then 16 million colors on that wall.
> It looks like 256!

It might be. And there are definitely less than 16 million colors on 
that wall! 24 bit color is 8 bits per component, you have 256 levels of 
red, green, and blue. This means you also only have 256 levels of gray, 
since those three are equal in gray colors. If the only difference 
between the colors is the intensity, you can sometimes see the banding, 
even with 24 bit color.

-- 
Christopher James Huff - Personal e-mail: chr### [at] yahoocom
TAG(Technical Assistance Group) e-mail: chr### [at] tagpovrayorg
Personal Web page: http://chrishuff.dhs.org/
TAG Web page: http://tag.povray.org/

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Thanks for the info, but how do I reduce the banding?

> From: Chris Huff <chr### [at] yahoocom>
> Newsgroups: povray.macintosh
> Date: Mon, 24 Apr 2000 11:21:32 -0500
> Subject: Re: Bands in graditations
> 
> In article <B529041B.B39%dav### [at] maccom>, David
> <dav### [at] maccom> wrote:
> 
>> Normally, I can not see the bands. In this picture only, I can.
>> I can tell that there are less then 16 million colors on that wall.
>> It looks like 256!
> 
> It might be. And there are definitely less than 16 million colors on
> that wall! 24 bit color is 8 bits per component, you have 256 levels of
> red, green, and blue. This means you also only have 256 levels of gray,
> since those three are equal in gray colors. If the only difference
> between the colors is the intensity, you can sometimes see the banding,
> even with 24 bit color.
> 
> -- 
> Christopher James Huff - Personal e-mail: chr### [at] yahoocom
> TAG(Technical Assistance Group) e-mail: chr### [at] tagpovrayorg
> Personal Web page: http://chrishuff.dhs.org/
> TAG Web page: http://tag.povray.org/

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In article <B529DDFE.B3F%dav### [at] maccom>, David 
<dav### [at] maccom> wrote:

> Thanks for the info, but how do I reduce the banding?

You could add some randomness to the wall texture, make the color very 
slightly uneven or add a very slight normal. This would at least break 
up the banding so it isn't noticeable.

-- 
Christopher James Huff - Personal e-mail: chr### [at] yahoocom
TAG(Technical Assistance Group) e-mail: chr### [at] tagpovrayorg
Personal Web page: http://chrishuff.dhs.org/
TAG Web page: http://tag.povray.org/

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Thanks!

> From: Chris Huff <chr### [at] yahoocom>
> Newsgroups: povray.macintosh
> Date: Mon, 24 Apr 2000 13:54:00 -0500
> Subject: Re: Bands in graditations
> 
> In article <B529DDFE.B3F%dav### [at] maccom>, David
> <dav### [at] maccom> wrote:
> 
>> Thanks for the info, but how do I reduce the banding?
> 
> You could add some randomness to the wall texture, make the color very
> slightly uneven or add a very slight normal. This would at least break
> up the banding so it isn't noticeable.
> 
> -- 
> Christopher James Huff - Personal e-mail: chr### [at] yahoocom
> TAG(Technical Assistance Group) e-mail: chr### [at] tagpovrayorg
> Personal Web page: http://chrishuff.dhs.org/
> TAG Web page: http://tag.povray.org/

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