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> Hello,
>
> this is my first post here. I just registered as I am looking for some help. I
> like to use povray for rendering LEGO models.
>
> Here is my topic:
> Rendering a LEGO Helicopter I realised a non-realistic effect: On the vertical
> flank of the rotor blade there are some yellowish reflections (see green flags:
> http://bricksafe.com/files/papacharly/reflections.jpg ). According to the focal
> blur settings these reflections should also be blurred. But as you can see,
> these reflections are razor-sharp and not blurred at all!
>
> Does anybody has an idea what is going on and how this can be resolved?
>
> I use povray 3.7.0
>
> Many thanks and kind regards from germany
>
> papacharly
>
>
>
>
What I see is the normal, physicaly correct bluring. There is nothing to
be resolved, except, maybe, some incorrect assumption or expectation.
The bluring of the reflection depends on the total distance between the
camera and whatever get reflected, not only the distance between the
camera and the reflecting surface. This differs totaly from any kind of
faked, post-process, focal bluring where you only get distance
information up to the first ray intersection.
Also, if you have a lense like object, what you see through it will be
affected by it's focussing effect.
If you render a scene where you have a reflective floor and some object
that is beyong the focal point and get blured when viewed directly,
then, it's refection will be as blured as the object itself.
Sample case:
#version 3.7;
global_settings{assumed_gamma 1}
plane{y,0 finish{reflection<0.5,1,0.6>}}
box{<3,0,50><-3,10000,50> pigment{rgb<1,1,0>}}// OUT of focus
cylinder{<-5,0,0><-5,100,0> 1 pigment{rgb<0.9,0.2,0.1>}}//in focus
sphere{<5,2,0>2 pigment{rgb<0.1,0.3,1>}}//also in focus
camera{location<0,5,-50> look_at 0
focal_point 0
blur_samples 9 35
aperture 10 // very broad to beter show the effect
}
light_source{<30, 0,-30>rgb 1 }
The yellow box is out of focus as is the totality of it's reflection.
The red cylinder and blue sphere are in focus. Their reflections are
also correctly in focus everywhere.
Alain
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"Papacharly" <nomail@nomail> wrote:
> Thanks for your fast and detailed response, Alain, as well for your example.
>
> Unfortunately, I have to admit that you're completely right: This effect is
> physically absolutely correct.
>
> But I have doubted that until I did a real life test setup using a real camera.
It's also easy to prove simply by viewing the world through a mirror held very
close to the eye :) The phenomenon also caught me short the first time I
encountered it, too.
Great model & rendering, BTW! Must have taken a long time to trace. Did you use
LGEO parts?
Sam
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