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I am currently trying to learn how to use rigacar to create a scene of a car racing through the tunnel. I am having issues when I try to add motion blur to the wheels. With no motion blur, the wheels spin fine as seen below. But as soon as I add motion blur the wheels start to become transparent in some sections. This is not desirable because it makes the car seem to jerk around as you can see in the second video. It also isn't physically correct because the tire occupies the same space frame to frame, just different parts of the tire.

No motion Blur With Motion Blur

No settings have been changed between the renders besides motion blur. I have done tests without denoising, that isn't the problem. Increasing the sample amounts from 128 to 512 had no effect. The wheels are centered at their origin of rotation. I am using Rigacar car generator. The wheels are instances of a separate collection to speed up viewport rendering. With larger shutter settings (increased from .5 to .8) the effect becomes worse.

Edit: I have attached the blend file for anyone who can take a look at it.

Edit: I have done additional tests. Removing the mesh lights and replacing them with actual lights does not fix the problem. Removing all lights does not fix the problem. Hiding the tunnel and rendering it against a blank background does not fix the problem. Changing the camera angle does not fix the problem. The wheels do not wobble in the viewport

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The issue appears to be with the way that I created my instances. The origins of the instances of the wheels are at the center of the instances making them move smoothly in the viewport. However, the source of the instances has the origin of the tire set not at the center of the wheel.

To fix the problem: I applied all the modifiers on the tire tread and centered the tire's origin.

I also had to rebuild parts of the scene and the following paths in order to implement the new instances.

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