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Manual - Blender 2.48

[edit] Spot Volumetric Effects

The Shadow and Spot panel for a Spot lamp, with halo controls highlighted.

Spot lights also can produce “volumetric” effects. See this page for more information about what it means.

Halo

The Halo button allows a Spotlight to have a Volumetric effect applied to it. This button must be active if the Volumetric effect is to be visible. Note that if you are using buffered shadows, you have extra options described in the “Spot Buffered Shadows” page.

HaloInt

The HaloInt (Halo Intensity) Numeric Slider field controls how Intense/Dense the Volumetric effect is that is generated from the light source. The HaloInt value has a range of between 0 and 5. By Default the value of the HaloInt Numeric Slider field is ignored because the Halo button is not active. To make HaloInt have an effect make sure the Halo button is active. The lower the value of the HaloInt slider the less visible the Volumetric effect is, while higher HaloInt values give a much more noticeable and dense volumetric effect.

Light with 0 HaloInt.	Light with .1 HaloInt.
Light with .5 HaloInt.	Animation showing the effect of differing HaloInt values, click to see.

Blender only simulates Volumetric lighting in Spotlights when using Blenders Internal Renderer. This can lead to some strange results for certain combinations of settings for Light Energy and HaloInt.

For example having a Spotlight with 0 or very low light Energy settings but a very high HaloInt setting can result in Dark/Black Halos, which would not happen in the real world. Just be aware of this possibility when using Halos with Blenders Internal Renderer.

Dark Halo with low Energy light.

[edit] See Also

• Shadows
• Spot light source
• Spot Buffered Shadows

Manual