Motion blur without movement

[Furnace]

Hi,
I'm creating a 360 of a car, the idea is sort of 'bullet time', so the car and wheels are static but I want the wheels to have motion blur to look like it's moving in a snapshot of time - anybody done anything like this before? From what I can see with Max and Vray motion blur the object has to be actually moving, it can't be faked.

Thanks in advance for any ideas.

[Alan Iglesias]

Hi,
I'm creating a 360 of a car, the idea is sort of 'bullet time', so the car and wheels are static but I want the wheels to have motion blur to look like it's moving in a snapshot of time - anybody done anything like this before? From what I can see with Max and Vray motion blur the object has to be actually moving, it can't be faked.

Thanks in advance for any ideas.

Hmmm..my best guess would be to take the number of frames in your animation and multiply by 360, and then subtract from that a small amount until each frame rotates the wheel exactly 360 degrees. Each frame will have the wheel in the exact same position in each frame, simulating your "bullet time" effect. Make sure that each wheel's rotation curve is set to Linear in the Curve Editor so that the wheels do not speed up and slow down, but rotate at a steady speed.

Later...

So I tried this and came up with these settings and it worked. Using 100 frames, I rotated the wheels 35999.99 degrees using the Euler XYZ controller with tangents set to Linear. This rotated the wheels exactly 360 degrees for each frame. They are moving, but you don't see it...much like the "wagon wheel strobing" in western movies back in the day when a wagon wheel was rotating at a speed that was matching up (spoke-wise) with the 24fps they were shooting in.

The camera of course had to be set to make the motion blur look good, and a full rotation every frame was making for some very exaggerated motion blur. So, using a Vray sun and sky, I set the shutter speed to a 500th of a second and compensated for exposure with an f-stop of 6.0.

I'm rendering a test animation now and I'll post the link when it is done.

Hope this is helpful,

-Alan

PS - Here's the link to the test animation: http://alaniglesias.com/BulletTime.mp4