Motion blur noise

Problem: Insufficient temporal sampling of shading or textures.

See MB Texture Samples in Render > Editors > Render Stats.

If the texture looks grainy, increase MB Texture Samples (under Render Stats) for the object. This marginally increases rendering time.

See MB Shading Samples in Render > Editors > Render Stats.

If the specular looks noisy, increase MB Shading Samples (under Render Stats) for the object. This noticeably increases rendering time; increase MB Shading Samples only when absolutely necessary.

Large objects do not motion blur correctly

A large object that stretches way beyond the view is clipped by the renderer. This clipping is done properly when the object is not motion blurred, but may clip incorrectly when the object is motion blurred.

See Mesh Tolerance (cm) in Render > Globals.

• Change the Mesh Tolerance value (under Render Globals).

Motion blur does not work

There are two possible causes:

• If you are raytracing, this is a known limitation.

  See Motion Blur in Windows > Editors > Cameras.

• If only the camera is animated, and nothing else (that is, a flyby), make sure that Motion Blur is ON for the camera (in the Camera Editor).

Rendering with motion blur

Problem: Rendering with motion blur produces grid-like artifacts, or Rendering with motion blur causes triangles to disappear.

Some large triangles may extend beyond the camera and near clipping planes. Objects may be too close together, causing interpenetrating problems for motion blur.

Decrease the Mesh Tolerance value (under Render Globals). Move surfaces that may be too close together further apart.

Using lights and motion blur

Problem: Spot light shadows and light projections do not motion blur.

This is a known limitation.

For shadows, blur the shadow by decreasing the Resolution (under Shadow Casting parameters). For projector lights, apply a solid projection texture to the object rather than using the light projection.

Solid textures do not motion blur correctly

This is a known limitation. Surface textures motion blur correctly.

Use the Convert Solid Tex option in the Render > Multi-lister (see Convert a solid texture to a File texture).

If the moving object is a patch, use Convert Solid Tex and apply the pix file as a File texture.

See Project to UV - Apply Mapping in Render > Multi-lister .

Using warped objects and motion blur

Problem: Warped objects do not motion blur when warp parameters are animated.

When a warp parameter is animated, the resulting changes in the shape of the warped object are not motion blurred. An object moving through a warp will be motion blurred correctly.

Move the object relative to the warp.

Transparent surfaces

Problem: Chatter in motion blurred textures moving behind transparent surfaces.

Motion blurred textures moving behind transparent surfaces may show chatter in the texture.

See MB Shading Samples in Render > Editors > Render Stats .

Increase MB Shading Samples for the transparent surface.

Fast moving objects

Problem: Motion blurred textures may appear streaked or noisy for fast moving objects.

Do one of the following:

See MB Texture Samples in Render > Editors > Render Stats .

• Increase MB Texture Samples for the textured surface.

  See MB Shading Samples in Render > Editors > Render Stats .

• If the motion blur of specular highlights, bump maps or displacement maps is noisy, increase MB Shading Samples for the textured surface. This will increase rendering time, so try increasing MB Shading Samples by one for each test render until the streaks or noise is eliminated.

Related Information

• Optimization
• Render > Multi-lister
• Render > Editors > Render Stats