Motion Blur and Instances Issues

[Tommes]

Hi guys,

I discovered some strange behavior, when it comes to parented instances and cameras.

Unparented Camera

Here you could see some instances and some regular objects which are all parented to a Null which is moving from right to left. The camera has a locked position. The three objects in the middle have correct motion blur applied, but the instances have no motion blur at all.

Parented Camera

Now I have parented the camera to the moving Null. In relation to the objects the camera should have a locked position, which is true for the three objects in the middle, but not for the instances, which are now blured. Bad behavior, bad.

Here is the scene file:

LightWave.zip

(443.52 KiB) Downloaded 175 times

[juanjgon]

You can't set the motion blur length above 100% ... it is not supported by the plugin, and adds wrong motion blur data to the instances. Please, set the length to 100% or less to fix your issues.

Also rememeber that the instances and deformations motion blur is only available in the final F9/F10 rendering. Out of the rendering stage LightWave can't send to the external render plugins the instances MB information. If you render your scene with F9 all works fine.

-Juanjo

[Tommes]

Thanks for the heads up. But I still think there is something weird when it comes to instance motion blur Will dig into it a little deeper. Maybe I could come up with a scene for you to test. But now I know I have to F9/F10 it to really test it. Thanks

[juanjgon]

There is at least one known issue with the instances motion blur: if you instance objects over a surface that has deformations (bones, morphs, dynamics ...), the motion due to the base mesh deformation can't produce motion blur in the instances. This is a limitation of the Lightwave SDK.

-Juanjo