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diegooriani
04-21-2009, 07:32 AM
Using the image below as reference I have a few questions on how to achieve something more realistic on my render.

Here are the questions:

1. Where I control the smoothness of raytracing shadows?
As you can see the shadows in the image are too sharp.

2. How can I make the colours of the textures bounce off and cast on other surfaces?
Right now the nothing is being casted..

3. Why do I have this strange division over my surface?
The material used on that surface is Blinn and there are 3 different ligths in this scene including a point light, ambient light and directional light. All with raytracing shadows active.

http://s3.amazonaws.com/scrnshots.com/screenshots/152283/final_gatheringjpg

I appreciate the help.
D
klingspor
04-24-2009, 10:53 PM
It would probably be helpful to note which program you are using.
diegooriani
04-27-2009, 09:54 AM
Sorry about that I completely forgot to post this information.

I am using Autodesk Maya 2009.
kanooshka
04-27-2009, 01:02 PM
Hi diegooriani, First I'd like to suggest starting lighting with only one main light. Once you get that light looking exactly the way you want then try adding in more lights to complement your initial key light.

1. For raytraced shadows there are mainly 2 ways to create shadows.
a. Use and arealight
b. Increase the light angle of your current light under the raytrace shadows options.
remember, the softer raytraced shadows, the longer the render time

2.
a. One thing I've noticed is that in mental ray final gather does not throw light colors as prominently as GI does. FG is more noticeable when using a very bright shader. At this point in your render I would not worry about the colored bounce lights yet and focus more on your direct lighting. You also should not need an ambient light if you are using final gather.
b. The amount of direct illumination or the ambient light itself may have effectively "masked" the color contributed bounced light therefore making the effect almost invisible.

3. I think you mixed up your number 2 and 3 in the image so I'm assuming you did. The division appears to be a reflection of a wall that is behind the objects. Try turning reflection off on the surface. If the division disappears you know that the reflection is causing the issue.
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04-27-2009, 01:02 PM
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