I have to confess I cheated.  This is a combination of two renders.  The low
quality render has fewer artifacts on the blinds because it just smoothes them
over, but lots of artifacts around the ceiling.  The higher quality render cuts
down on artifacts around the ceiling, but causes a lot of artifacts on the
blinds.  I went all the way up to count=1600 without any improvement.  Wherever
there's a gap there are a lot of artifacts.  Does this mean I have not balanced
count and error_bound correctly, or does anyone have other ideas on how I might
improve or fake the rendering quality?  Either way, my tip for the day?  Stay
away from blinds.

 - Ricky

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"triple_r" <rre### [at] hotmailcom> schreef in bericht 
news:web.47f617807305684bae42298f0@news.povray.org...
>I have to confess I cheated.  This is a combination of two renders.  The 
>low
> quality render has fewer artifacts on the blinds because it just smoothes 
> them
> over, but lots of artifacts around the ceiling.  The higher quality render 
> cuts
> down on artifacts around the ceiling, but causes a lot of artifacts on the
> blinds.  I went all the way up to count=1600 without any improvement. 
> Wherever
> there's a gap there are a lot of artifacts.  Does this mean I have not 
> balanced
> count and error_bound correctly, or does anyone have other ideas on how I 
> might
> improve or fake the rendering quality?  Either way, my tip for the day? 
> Stay
> away from blinds.
>
we should need to see your radiosity settings...

Thomas

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"triple_r" <rre### [at] hotmailcom> wrote:
> I have to confess I cheated.  This is a combination of two renders.  The low
> quality render has fewer artifacts on the blinds because it just smoothes them
> over, but lots of artifacts around the ceiling.  The higher quality render cuts
> down on artifacts around the ceiling, but causes a lot of artifacts on the
> blinds.  I went all the way up to count=1600 without any improvement.  Wherever
> there's a gap there are a lot of artifacts.  Does this mean I have not balanced
> count and error_bound correctly, or does anyone have other ideas on how I might
> improve or fake the rendering quality?  Either way, my tip for the day?  Stay
> away from blinds.
>
>  - Ricky

Have tried placing an additional area light right in the doorway itself?  The
second area light would be much dimmer of course, and would span the entire
size of the doorway.

Very nice image, by the way.  Despite the artifacts on the blinds, I would not
have known it was a render if were posted elsewhere.  They just look textured
or dirty.  Adds to the realism, even.  :)

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"Thomas de Groot" <t.d### [at] internlDOTnet> wrote:
> we should need to see your radiosity settings...

Sorry.  Of course.  Here are the settings for the high quality render:

radiosity {
  normal off
  count 300
  recursion_limit 2
  error_bound 0.35
  pretrace_start 0.08
  pretrace_end 0.02
}

This gives a lot of artifacts.  If I decrease the count to 50 and increase the
error_bound to 0.5, it looks better, but the detail disappears.  That also
increases artifacts around the corners of the walls.  Tried max_sample, but in
reading over the radiosity docs, perhaps I need a lower pretrace_start?

 - Ricky

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"Kirk Andrews" <kir### [at] tektonartcom> wrote:

> Have tried placing an additional area light right in the doorway itself?  The
> second area light would be much dimmer of course, and would span the entire
> size of the doorway.

Yes, there are 3x3 mosaics of area lights that cover the whole window.  One
inside the room and two outside.  There's also a sky_sphere with an rgb 1
pigment.  Without the area lights the render is a lost cause, but the area
lights don't solve everything either.

 - Ricky

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"triple_r" <rre### [at] hotmailcom> wrote:
> I have to confess I cheated.  This is a combination of two renders.  The low
> quality render has fewer artifacts on the blinds because it just smoothes them
> over, but lots of artifacts around the ceiling.  The higher quality render cuts
> down on artifacts around the ceiling, but causes a lot of artifacts on the
> blinds.  I went all the way up to count=1600 without any improvement.  Wherever
> there's a gap there are a lot of artifacts.  Does this mean I have not balanced
> count and error_bound correctly, or does anyone have other ideas on how I might
> improve or fake the rendering quality?  Either way, my tip for the day?  Stay
> away from blinds.
>
>  - Ricky

First, that's a very nice image.  Congratulations however you made it.

I, cannot, however endorse your admonition to stay away from blinds. Our very
survival depends on window blinds.  Without them, it would be curtains for
everyone!  ;-)

(I'd say I was sorry for the horrid pun, but I don't think anyone would believe
me
at this point.)

Best Regards,
Mike C.

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As others have said it's a beautiful render, and I would never have thought the
artifacts were such if you hadn't said so.

> Sorry.  Of course.  Here are the settings for the high quality render:
>
> radiosity {
>   normal off
>   count 300
>   recursion_limit 2
>   error_bound 0.35
>   pretrace_start 0.08
>   pretrace_end 0.02
> }

I would definitely try lowering pretrace_end, and maybe an error_bound of 0.2 or
0.1. Also, make sure minimum_reuse is nice and small too - the default is 0.015
but you could try 0.01 or 0.005. All of this will slow the render
significantly, but I have found it effective (although every radiosity scene is
different). You may also need to raise count a little too but see how it goes.

Bill

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"Mike the Elder" <nomail@nomail> wrote:

> First, that's a very nice image.  Congratulations however you made it.
>
> I, cannot, however endorse your admonition to stay away from blinds. Our very
> survival depends on window blinds.  Without them, it would be curtains for
> everyone!  ;-)
>
> (I'd say I was sorry for the horrid pun, but I don't think anyone would believe
> me
> at this point.)

Thanks, but you're right.  No forgiveness.

 - Ricky

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"triple_r" <rre### [at] hotmailcom> wrote:
> "Mike the Elder" <nomail@nomail> wrote:
> > I, cannot, however endorse your admonition to stay away from blinds. Our very
> > survival depends on window blinds.  Without them, it would be curtains for
> > everyone!  ;-)
> >
> > (I'd say I was sorry for the horrid pun, but I don't think anyone would
> > believe me at this point.)
>
> Thanks, but you're right.  No forgiveness.

Someone should get the drop on him before he goes off the rails. Then he should
pull himself together.

:\

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"Bill Pragnell" <bil### [at] hotmailcom> wrote:
> As others have said it's a beautiful render, and I would never have thought the
> artifacts were such if you hadn't said so.

I guess you're right.  It's just that the perfectionist in me would rather get
rid of the radiosity artifacts and simulate the same effect with a texture than
consider the artifacts a feature.
>
> I would definitely try lowering pretrace_end, and maybe an error_bound of 0.2 or
> 0.1. Also, make sure minimum_reuse is nice and small too - the default is 0.015
> but you could try 0.01 or 0.005. All of this will slow the render
> significantly, but I have found it effective (although every radiosity scene is
> different). You may also need to raise count a little too but see how it goes.

Thanks!  I'll try that.

 - Ricky

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