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pnevai
05-25-2006, 12:47 AM
Something so simple to achieve on film or even video is elusive in LW.

I am talking about light smearing as when you have a long exposure time on film in a low light environment, or light streaking when using video.

Vector blur motion blur and particle blur really do not do the effect justice. Is there a good effective technique for making bright spots on a object smear when animated without the entire object also blurring to unrecognizeability?

adk
05-25-2006, 01:59 AM
Don't know if this is what you're after but it might be a start.

http://www.newtek.com/forums/showthread.php?p=17671#post17671

visugeek
05-25-2006, 02:23 PM
You might want to render the lights in a seperate pass and give them a directional blur in comp.

duke
06-10-2006, 02:29 AM
Re-render it out (half res if you want) with a completely insane motion blur amount, like 1000%. You'll need high AA and turn on dithered motion blur. Isolate the highs in post and comp it over the top.

Defiance
06-11-2006, 09:50 PM
There's also an old method where you use the previously rendered frame as the background for the current frame. Have an animation like this and the last frame you get will have everything that was moving smeared. It's a weird technique, but you basically set up your background to use an image sequence. And the image sequence is the saved file name of your animation. So each frame that gets output gets part of the image sequence. It's from the old pre-L[6] days where you unwrapped a model for texture mapping by rotating the camera around it. You'd have this slit which lets you scan a strip at a time, and the weird compositing technique lets you make an unwrapped thing.

I've set this up in 7.5 before, I just don't remember how exactly. But it wasn't too hard. It might be what you're looking for. You can probably do the same in a comp package, but I like using Lightwave for everything. :)

DMarkwick
06-23-2006, 03:25 PM
There's also an old method where you use the previously rendered frame as the background for the current frame. Have an animation like this and the last frame you get will have everything that was moving smeared. It's a weird technique, but you basically set up your background to use an image sequence. And the image sequence is the saved file name of your animation. So each frame that gets output gets part of the image sequence. It's from the old pre-L[6] days where you unwrapped a model for texture mapping by rotating the camera around it. You'd have this slit which lets you scan a strip at a time, and the weird compositing technique lets you make an unwrapped thing.

I've set this up in 7.5 before, I just don't remember how exactly. But it wasn't too hard. It might be what you're looking for. You can probably do the same in a comp package, but I like using Lightwave for everything. :)

Oh wow that sounds great :) Can you also use image processing on the background image & have it constantly brightening or darkening etc? Gotta try this :)