I just discovered that you can make also focal blur with the targa
averager.
  You may say "Hey! There is focal blur in povray already."
  That's right. But you may have noticed that focal blurred images made with
povray are grainy, with random and annoying noise, no matter how many blur
samples you use. I don't know exactly why this happens, but I suppose that
it's because povray shoots the blur samples at random, with different random
values from pixel to pixel. This seems to produce that random noise.
  The focal blurred images made by averaging are a lot smoother.

  For more info see http://iki.fi/warp/PovUtils/average/focalblur.html

-- 
                                                           - Warp. -

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On 7 Sep 1998 04:31:37 -0500, Nieminen Mika <war### [at] assaricctutfi>
wrote:

>  I just discovered that you can make also focal blur with the targa
>averager.
<SNIP>
>
>  For more info see http://iki.fi/warp/PovUtils/average/focalblur.html
>
>-- 
>                                                           - Warp. -

I looked at the samples, and I especially like the foreground blurring
bettter with your technique. Noisy foreground blurring was always the
main reason I never experimented much with POV's focal blur feature.
Your techinique looks very promising.

Later,
Glen Berry

Home -> http://www.ezwv.com/~mclilith/index.html
IMP  -> http://www.algonet.se/~jhubert/MovieProject/index.html

To reply via personal email, remove the "X" from Xno### [at] ezwvcom

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Nieminen Mika <war### [at] assaricctutfi> wrote:

>  I just discovered that you can make also focal blur with the targa
>averager.
>  You may say "Hey! There is focal blur in povray already."
>  That's right. But you may have noticed that focal blurred images made with
>povray are grainy, with random and annoying noise, no matter how many blur
>samples you use. I don't know exactly why this happens, but I suppose that
>it's because povray shoots the blur samples at random, with different random
>values from pixel to pixel. This seems to produce that random noise.
>  The focal blurred images made by averaging are a lot smoother.
>
>  For more info see http://iki.fi/warp/PovUtils/average/focalblur.html
>
>-- 
>                                                           - Warp. -

One of the problems (the other comes from focal_point and aperture
which can be easily solved now) of focal blur comes from the fact that
the values (even the "best" ones) provided in the documentation are
far from being accurate. If you dare to use really sharp values for
sampling, like:

   blur_samples 100
   confidence 0.999
   variance 1/255

you can easily get something like this:

http://www.geocities.com/Vienna/7709/s17.jpg

And here again, the problem is time... as always!
But here you can control the depth of field more efficiently.
--- 
Francois DISPOT
e-mail woz### [at] NOSPAMclub-internetfr
http://www.geocities.com/vienna/7709

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Francois Dispot <woz### [at] NOSPAMclub-internetfr> wrote in article
<35f447ba.943075@news.povray.org>...
>  Nieminen Mika <war### [at] assaricctutfi> wrote:
> 
> >  I just discovered that you can make also focal blur with the targa
> >averager.
> >  You may say "Hey! There is focal blur in povray already."
> >  That's right. But you may have noticed that focal blurred images made
with
> >povray are grainy, with random and annoying noise, no matter how many
blur
> >samples you use. I don't know exactly why this happens, but I suppose
that
> >it's because povray shoots the blur samples at random, with different
random
> >values from pixel to pixel. This seems to produce that random noise.
> >  The focal blurred images made by averaging are a lot smoother.
> >
> >  For more info see http://iki.fi/warp/PovUtils/average/focalblur.html
> >
> >-- 
> >                                                           - Warp. -
> 
> One of the problems (the other comes from focal_point and aperture
> which can be easily solved now) of focal blur comes from the fact that
> the values (even the "best" ones) provided in the documentation are
> far from being accurate. If you dare to use really sharp values for
> sampling, like:
> 
>    blur_samples 100
>    confidence 0.999
>    variance 1/255
> 
> you can easily get something like this:
> 
> http://www.geocities.com/Vienna/7709/s17.jpg
> 
> And here again, the problem is time... as always!
> But here you can control the depth of field more efficiently.

	This is nothing to do with focal blur, I just wanted to say WOW! Excellent
image ! Every now and then I see an image and think "If only I had the
skill to produce something that photorealistic with POV", this was one of
those times.

-- 
Scott Hill
Sco### [at] DDLinkscouk
Software Engineer (and all round nice guy)
Company homepage : http://www.ddlinks.demon.co.uk

"The best trick the devil ever pulled was convincing people he didn't
exist..."
								- Verbal Kint.

"the Internet is here so we can waste time talking about nothing in 
 particular when we should be working" - Marcus Hill.

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