Tip #489: Simulate Speed with a Channel Blur
… for Visual Effects
Tip #489: Simulate Speed with a Channel Blur
Larry Jordan – LarryJordan.com
As long as you blur only one channel, your image will stay mostly in-focus.
The channel blur effect blurs one, two or all three color channels in a clip. (Red, green and blue are the three color channels in any clip.) By selectively blurring a single channel you can, for example, imply speed or create a halo, without sacrificing apparent focus.
Here’s a detail from an air show clip. The bottom section is the source. The middle blurs just the blue channel. The jet develops a “halo,” which, to me, makes it seem like it is flying really fast.
Only when we blur two channels do we lose focus and, now, the jet looks like it’s part of a bad dream (top).
Play with this and see what you think. If you blur the dominant color, you won’t lose much focus.
EXTRA CREDIT
Image courtesy of Hallmark Broadcast Ltd. www.hallmarkbroadcast.tv
Where is the channel blur effect in FCP X?
Philip:
360° Channel Blur.
Larry
Larry,
I tried that but it magnifies the entire scene. Is there a way the effect can be adjusted for a non-360 scene?
Thanks,
Philip
Philip:
There’s a Channel Blur in Motion, which was where I created the screen shot. None in FCP, if the 360° Channel Blur doesn’t work. You could create your own for FCP using Motion.
Larry
Got it. Thanks.