This tutorial is going to focus mainly on a single masking layer using the gradient, and a texture layer. The image can be found here: [link]

I made some Doodad layers with some "shaping gradients" (those containing only 2 or 3 color points) to start this fractal. I added 3 different coloring layers that you can analyze at your leisure. I added a SFBM II layer for texture. Because I didn't want this texture to just uniformly overlay the spiral, I made a gradient mask to confine the texture where I wanted it. In this case I didn't want the texture to cover the highlighted areas of the spiral. I duplicated layer 5 and if you look at the gradient of that layer, you will see that it has 3 color points. Two of them are dark and one is light green. I linked the color and the opacity by hitting Ctrl L. Then since I wanted to keep the texture off of the highlighted points of the spiral, I pulled down the control point in the opacity level that matched the highlight color until the opacity was 0 (or you can type in 0). I then moved this layer under my texture layer and hit "Use as Mask" and made the merge mode of the texture layer "Overlay". The texture was still covering more of the spiral than I wanted, so I went to the gradient of the mask layer and moved the poisition of the control points until I had the texture just where I wanted it: just in the central portions of the spiral arms, gently feathered toward the highlights. If you look at just my texture layer with the mask attached, by hitting the shift key and clicking the visible icon next to the layer, you will see how the mask has opaque areas where you can see the texture and transparent areas indicated by the checkered pattern. The transparent areas are the result of the color point that you pulled down to 0 in the gradient. Essentially, you make the places transparent where you don't want any texture to show. Now hold down the shift key and click the visible icon again to show all the layers again. Go to the mask layer and click the transparency icon next to the little magnifying glass on that layer. You will see how heavily the texture would show without that mask. Here is the upr:

sam_polyJuliaWithDuddads1bLayered+mask1a {
; Copyright © 2006 by Mary C. Thornton.
; Feel free to tweak. :>
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}