Well It has been a long while since I had a play with Povray and even longer
since I posted an image.  So to make up for lost time I'm posting 2.

Just a little experiment using 3 point lighting and radiosity.  I know this
object has been modelled hundreds of times but I just wanted something
simple to get me back into things.  I even put a checkered floor in for good
measure ;-)

Both images are the same apart from 1 has focal blur.

Comments etc.. etc.. please

Dave.

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No focal blur

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Attachments:
Download 'cube_rad.jpg' (66 KB)

Preview of image 'cube_rad.jpg'

Image with focal blur

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Attachments:
Download 'cube_rad_blur.jpg' (54 KB)

Preview of image 'cube_rad_blur.jpg'

Very nice.

Perhaps you'd like to try an image with darker tones and more shadows?
That's the best setup to master 3-point lighting.

Regards,

Roberto

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Davey B wrote:
> 
> No focal blur

This image has some nice roto feelism... er... um... photo realism.

-- 
Ken Tyler

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Hey,

It looks pretty good! The focal blurred version seems a bit exaggerated
though; not like a good photo.

If you want to get rid of the artificial look, the reflections could use
some blur, or at least a pattern to split up the regularity. Also, when ever
there are reflections, there ought to be some specular highlight, but I
can't see it? Well, you don't need to use the specular/phong keywords, of
course. These are going to look fake. They are meant to substitute a real
source of light; an object that is visible, and lit. As you know,
light_source's are not visible by default. You could try cluttering some
glows for example, to simulate an area of light.. Or use media; it's slower
but without the bugs that still plague the glow feature in MegaPOV.

You could also use box primitives, with a texture that simulates a glowing
area. That's what I've been using recently, and it's probably the fastest
method, renderwise.

Regards,
Hugo

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> If you want to get rid of the artificial look, the reflections could use
> some blur,

Yes that is something I noticed too.  I am just having trouble doing an
averaged texture in Moray.

> Also, when ever there are reflections, there ought to be some specular
highlight, but I
> can't see it?
> You could also use box primitives, with a texture that simulates a glowing
> area. That's what I've been using recently, and it's probably the fastest
> method, renderwise.

I tested this idea but have come across a problem.  I placed a bright white
sphere around each light source (just as place holders) and then rendered
the scene.  Not one of the spheres got reflected in the cube.  Now if I have
understood you correctly this was what you were talking about.  It seems
that my camera and light angles are not going to allow this approach though.
May have to move something and see what happens.

Thanks

Dave.

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> I placed a bright white sphere around each light source
> (just as place holders) and then rendered the scene.
> Not one of the spheres got reflected in the cube.

That is what I'm talking about, and they should be visible in the
reflections.

I assume you're using "looks_like" in the light_source definition? Please
remember not to translate the spheres into position; keep them at origin
because they will follow the light sources anyway. (This is one mistake I've
done several times!)

How big are those spheres? If the light is far away, the spheres needs to be
pretty big - usually bigger than you expect, to make a good specular
highlight.

Are the spheres white as of  rgb <1,1,1> ? Your sky_sphere that surrounds
the world, is also white, so you need to go much higher with the rgb in your
light_sources. Same goes if you're using fog.

Have you given the spheres an ambient value of 1?  I think it's a good idea,
along with diffuse 0. To make sure the spheres are properly lit with the
strength you've set in pigment.

Right now I can't think of other pitfalls, but I'm sure you'll make it work.
:-)  As you say, such spheres are placeholders; they won't look too good
without a glowing texture or some heavily blurred reflections. Also, they
will look pretty much like specular/phong keywords because they are simply
spherical.. Of course, the sun is also a sphere (surrounded by a strongly
lit area of the sky) but if we say, the sun is your key-light, I would use
some other shapes for the fill-light /back lights, along with some much
weaker specular values..

Regards,
Hugo

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Did you see that ?

http://povgaleries.tuxfamily.org/defis/PageDefi001.php

;-)

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Yes I have seen that before hence my reference to this object being done
hundreds of times before ;)

Thanks

Dave

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