Over crank Motion Blur (Action)


I just reached the 200 samples limit in Action but still get some fragmentation in my render. Any idea how to go beyond 200 samples in Action (or as a post fix)?

Would recursive ops be better for this?

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Well, it might be…

Lets try it!

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Q tal Julio. A couple of things:

Try outputting your action vectors and adding motion blur with batch motion blur, cranking it up. I believe there are also more settings to adjust here.
You could then add mblur to that output with another mblur node, multiple times.
Also try blurring your vectors output a bit in batch.
You could also try adding a stingray motion blur in your action to try doubling up.


Another PITA approach would be to duplicate your action, stretch out the animation to twice the length, render (presumably with better motion blur), then TW that render to half.


Thanks Malone!

*make sure to pre-render this. Trying to do so live with the motion blur TW would be painful.

One other thing you can try is upping the software AA in action. Though this will make the renders very slow.

Make the value of the fill way higher than 1.0 and open the shutter the whole way as well. You’re peaking the center.

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Expound please?

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If the fill value is way higher than 1 and the shutter is wide open the streaking should become considerably more pronounced. Think of car taillights at night on a long shutter.

Not in front of a machine right now but I seem to remember that working nicely.

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If the white value is one and you average that against 0 you get .5. Average a high value like 100 or something and what’s your average? 50. Clip that to 0-1 and it’s white at 50%.

So the white value just has to be high enough to average way higher. Sample that a few times with accumulation and you should be home.

In theory :joy:


Exactly, that’s the intended effect. A la “Akira Motorcycles”

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Here’s a batch with what I was thinking…

There’s two versions there. The first combines three different copies of the same setup with different phases on the motion blur.

The second copies out the animation and pushes it .5 frames and 1 full frame forward to simulate the same look but in a single node.

Hope it’s useful. There’s still stepping. But with digital cameras your would get stepping. Not with film though…

Edit: One thing to also add, once you’re happy with the look of the trails add a small number of software AA samples with a small about of softness to sample away your edges in the trails. The AA samples will move the render around slightly and average the results. The softness is how far it would move around. That value then get’s sampled by the MB samples temporally over your shutter duration X shutter value at the subsample so it’s a great way to smooth those edge out. On the single node setup I added 4 and 4 for AA and softness and it works a treat without getting computationally unmanageable.


Thanks! Will try your setup tomorrow

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If, perchance, you’re using particles to create this effect, you can crank the TimeSteps parameter over the maximum value of 80, by saving the action file, editing it with a text editor, and loading it back in…

Unfortunately said method doesn’t work with cranking the motion blur samples…


Interesting, but I guess doing so is going to drive the Action render very slow. But very interesting, is there a list of the crackable Action settings from a text editor?

Then you can lower the moblur sample number though.

And, no there is no list I know of. I had thought about editing the action file way back in version 5, when I was trying to open a setup from a newer version. Changing the version number got me halfway there :slight_smile:

This is the one I am experimenting with:
Esperma Light.zip (157.1 KB)

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Very cool Chris!

You still get some banding though…