Fractal Noise
by LGABoarder
on
May 18, 2007 at 8:38:35 pm
I've got two questions regarding fractal noise. First, how can I get an alpha channel out of it, I've tried all of the Blending modes through the effect itself and the layer and neither seem to make a difference (without something behind it). The reason this is important is that I want to apply Colorama to it and even when the fractal has an alpha (through Add when applied over my background) Colorama still colors the black areas.
Also, is it possible to roll the color through fractal noise rather than change the Evolution? If I was creating a flag, for example, I could just roll the Brightness through to create the effect of a flowing ripple.
Re: Fractal Noise by rjf e:613 on May 18, 2007 at 9:11:35 pm
1.) You want the colorama effect to NOT apply to the black sections, FULLY apply to the white sections and PARTIALLY apply to the grey sections? Try duplicating the fractal noise layer and putting an adjustment layer between these two noise layers. Apply colorama to the adj. layer and change its Track Matte mode to Luma (or Inv. Luma depending on the look you're going for). The top fractal noise layer will shut off automatically and you'll have it effected only on the whitest pixels. (you may need to precompose these three layers).
2.) You can animate the fractal noise layer itself right to left by adjusting the Offset Turbulence layer on the X axis. This parameter is found under the "Transform" sub-folder of the Fractal Noise effect. I do this all the time when wanting to create a rippling flag.
Re: Fractal Noise by rjf e:613 on May 18, 2007 at 9:19:44 pm
1.) CONTINUED... it occured to me after I posted that an adjustment layer isn't necessary. Still duplicate your fractal noise layer as before, but this time, ONLY apply colorama to the bottom of the two noise layers. Turn this layer's Track Matte to Luma (or inv. Luma) as before. The top layer will still shut off, and that's ok. Turn on the checkerboard background and you'll see that the black areas are indeed transparent.
The advantage here is that there's no adjustment layer affecting all of the other layers below it so a precompose may not be necessary (unless you like keeping things tidy).
