Peardian Wrote:Make a new image/canvas/file with the same dimensions as the image you're going to recombine. Make three layers, with the top two being the Alpha Channel image and Green Channel images you split from the original. The bottom layer should just be solid blue color (#0000FF).

Next, you need to blend the Alpha Channel image with pure red (#FF0000), with the blend mode set to "Multiply". I'd be more specific, but each program has its own way of doing it. The idea is to reduce the Alpha Channel image to only use the R of RGB. Similarly, you're going to blend the Green Channel image with pure green (#00FF00) with the blend mode set to "Multiply" again.

With those steps done, you will have three layers that hold the R,G, and B of your completed image. All that needs to be done is combine them. To do this, simply set the Blending/Mixing mode of the top two layers to Additive/Exclusion (I don't know why they use that term, Additive is better). The result will be the nice blueish-rainbow images you saw in DW.

I hope that's clear enough. I'm afraid I'm only familiar with the interface for Fireworks, so I can't really be more specific about buttons and such.

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Oh, you're using Fireworks? Great! Then I can definitely be more specific.

When you select any object, you get a set of options:
-a checkered box with "100" next to it, which is the Opacity
-a dropdown box that says "Normal". This is the blending mode
-a list of Effects, with Add/Remove (+/-) buttons

In the Blending mode drop-down box, simply select Exclusion.

Also, since you're using Fireworks, I can show you an easy way to multiply a color with the desired layers. (Note: Make sure you keep track of which one is which! The one that looks like light is coming from directly above is the one you make Green.) So, to multiply a color with an object:

-Click the + button
-In the "Adjust Color" category, choose "Color Fill"
-In the little box that comes up, change the drop-down box to say "Multiply"
-The default color is pure Red, which is good. If you're doing the Green Channel image, change it to pure green.

By the way, instead of making a layer for blue, you can also just set the Canvas Color to blue. This will have the same effect.