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Pixel2
02-05-2007, 03:18 PM
Hi!

I need some hep to try to resolve this error.

I have a scene illuminated with a sky dome with some material applied. My scene has some wild-card trees with some alpha channel.
I'm using a background object with some image.
My dome has a tag removing see by camera, transparency and refraction.

Problem. If I turn on transparency and refraction, the tree wild-cards will show as well the dome...

have I been clear?

thanks in advance
nutriman
02-05-2007, 04:00 PM
Hi Pixel2,

make sure your raydepth within the rendersettings will be sufficient.
Crank it up and see what happens.
Also: Do you use a background object or a sky object? The latter doesn't
work with alphas, you really need to have a background object or a sphere/ plane
in the background.
mattyt
03-07-2007, 02:38 PM
I have had this problem before and it is almost certainly insufficient ray depth in your render settings. try upping to 20 and work backwards from there.
andrasn
03-09-2007, 09:47 AM
Hi,

How is your Transparency in Render settings' General tab? Is it "with refraction"?

I can't see exactly in your image if the tree is a reflection or it's behind the window...

But I noticed in one of my projects that they are problems with reflected transparent objects if transparency is set to "No refraction". (And my Ray Depth is high enough, so that is not the problem.) They are black like in your render. Changing Transparency to "with refraction" solved the problem.

Cheers,
Andras
smia
03-09-2007, 10:39 AM
Hi,
I think the problem is the backround objekt. Better use a simple plain and map your image on this. Also the sky-objekt is not meant for this kind, better use a sphere-object instead.

Hope this suggestion helps,
greetings,
...s_e_m_i
robodesign
03-09-2007, 07:56 PM
The answer to life and everything:
- it is the 42th render engine limitation. Alphas plus any kind of fog or [I recall] volumetric light is causing that problem.

:).
STRAT
03-12-2007, 11:19 AM
Hi,
I think the problem is the backround objekt.

we've suffered from this before and also found the backround object to be the offender. try changing it to a mesh (ie, plane or sphere) or a sky object. we usually use the sky object.
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03-12-2007, 11:19 AM
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