… for Visual Effects
Tip #489: Simulate Speed with a Channel Blur
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.
Image courtesy of Hallmark Broadcast Ltd. www.hallmarkbroadcast.tv