Paint Shop Pro Channel Mask
For this image I used a technique similar to the one used for the jets in the previous example, but it is much simpler. This example involves splitting the image into channels and editing the channel to create a grayscale mask. It also demonstrates the layer matting commands.
Just as before, we will spit the image into its RGB channels. Colors > Channel Splitting > Split to RGB
Examine the channels and choose the one that preserves the most information in the area of the fireworks. In this case, it is the red channel. Discard the blue and green images and keep the red channel. We'll edit this image to produce a mask for the fireworks.
Because the fireworks are what we want to isoloate, we can simply paint away the white areas in the lower portion of this image. Select a good-sized brush, and paint away the white areas with pure black.
You may not notice it, but the black area surrounding the fireworks is still a few shades lighter than pure black. You can check a few areas with the eyedropper tool. Hold the eyedropper over an area of the image, and look at the color palette to check the RGB values. Pure black will show an RGB value of 0-0-0. Notice in my example the image is showing a value of 3-3-3, a bit lighter than pure black.
To quickly bump the gray areas up to pure black, go to Colors > Adjust > Brightness/Contrast.
Move the contrast slider up just a few points. In this case, increasing it to 5 is all we need. If you use too high a number you'll start to loose the gray around the fireworks and we don't want that.
If you repeat the eyedropper check, it should show that the background areas are totally black.
Now let's go to the original color image. In the layers palette, double click on the background and name the layer fireworks. I'm going to use another image as a new background.
Open the image you'd like to use for a background, select all, and copy. Return to the fireworks image and go to Edit > Paste as New Layer. Drag the new layer below fireworks in the layer palette.
Select the fireworks layer, go to Masks > New > From Image. Choose the grayscale image that was edited from the Red channel for the Source, and make sure "Source luminance" is selected, then click OK.
The background disappears allowing the layer below to show through.
There's one more step we can take to make the fireworks as vibrant as they should be. Go to Masks > Delete.
You will see a question pop up like the one shown here. Choose Yes. This deletes the mask while leaving the transparent areas.
Next go to Layers > Matting > Remove Black Matte. The fireworks will appear much more vibrant.
Any time you pull an image from its background, it's a good idea to try each of the three matting commands. Sometimes one will produce better results than another, and sometimes none of them appear to have any effect at all... it all depends on the combination of your foreground and background. But don't overlook them entirely because they can often make a world of difference.
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Some images from Nova Development's Art Explosion 600,000.