Thursday, April 1, 2010
Node Highlight: RGB Blur
Pretty dumb node for my first node highlight you say?
RGB Blur is a lifesaver!
It's first and primary duty is to smoth out gmask shapes. Gmasks always have a linear gradient which leaves a hard line at both the black and white ends of it. It completely sucks and there's no way to turn it off (Nuke, by contrast, has multiple gradient settings for gmasks), so what you do is pipe said mask into an RGB Blur and blur it up. Do it by eye. When the hard edge goes away, you win! Completely necessary.
The only thing that sucks about this is when you have to blur past the edge of the frame, which, because the blur doesn't have an imagination, will produce results that are less than ideal--vignettes for example tend to get this problem but are still better looking blurred than not.
Similarly, the "use matte" isn't all that useful as it will blur in areas outside of the matte (which is completely understandable, but makes it so you might as well just logic op-blend your shit together vs blurring through a matte) If you want to blur inside of a matte and not suck in the outside-of-matte areas, Sapphire's "Matte Blur" does a nice job of this.
In fact, the regular sapphire blur is probably generally nicer than the stock blur, but I think it's bad policy to use plugins when they aren't specifically necessary.