Radial Blur filter creates various zoom and spin motion blur effects. You can control the blur direction and smoothly vary between zoom, spiral and spin effects. Parameters: Blur Type "Constant" mode represents the real spin/zoom blur effect while "Soft" adds subtle directional blur. One-Way variations add not only blur, but a visual motion also. Size Controls the blur power. Value of 1.0 sets the maximum blur, but you can enter in edit field values from -4.0 to 4.0 and get more blur, but with a slightly reduced quality. Negative values set opposite-direction blur for One-Way modes. Distribution Controls the blur distribution over the image. Higher values limit the blur's power in the center. Direction Controls the blur direction. Value of 0.125 - spiral, 0.25 - spin blur. Center Controls the position of the blur center point. By keyframing the Center control, you could have the effect center track your subject's movement. Spiral Blur. You can control the blur direction and smoothly vary between zoom, spiral and spin effects. See also Radial Blur variations: RadialBlend - Blur an image and blend with the original.