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View Full Version : Good Motion Blur?



Tony3d
04-23-2013, 11:06 AM
Ok, what's the secret to getting a good motion blur? Just really need it for one frame still image.

stiff paper
04-23-2013, 11:14 AM
Practice.

stiff paper
04-23-2013, 11:24 AM
What version of LW?

Try:
Motion blur type "Photoreal." 50% blur length is usually good for most things. The more "Motion Blur Passes" you give it, the smoother it will look. Try starting with a value of 3. Of course, this will do catastrophic things to your render time (still image, though, so perhaps not the end of the world).

As a place to start, Minimum Samples = 1, Maximum Samples = 32, Reconstruction Filter = Box, Sampling Pattern = Low Discrepancy, Threshold = 0.06, Oversample = 0.5. See how that looks.

If it isn't nice enough, lower the Threshold value, try again. I've never gone below 0.01. 0.01 is a crazy number anyway. Just ask anybody.

Your render times will be nasty. Probably. But you said you wanted "good"...

More Oversample will make image blurrier and "softer." Can't imagine ever going over 0.7, but I have used 0.7 occasionally.

Tony3d
04-23-2013, 01:09 PM
Thanks.

stiff paper
04-23-2013, 02:07 PM
Actually, reading it back now, I think my attempt at advice lacked some info. The quality of the motion blur is mostly all about how many motion blur passes you give it. The samples and threshold stuff is about controlling the noise in the image, although it'll also affect the noise within the motion blur.

You have to try to balance everything. My approach is usually to start out by getting the image looking pretty good without the motion blur turned on, using the sampling settings, and trying to get the settings as low as possible while still giving a good quality image. By that I mean getting to the point where the antialiasing is still good and there's not too much noise, but my render time is not too crazy. Then I'll turn on the motion blur and adjust its settings until that looks good too.