Shrouded in mystery, perched high atop the Layer palette in both Photoshop and Photoshop Elements there sits a pop-up menu that's been baffling folks for ages. The menu of which I speak is called Blending Modes. You've probably clicked on it before and chosen a few of the strange words ontained therein only to be completely baffled by the effects, ranging from making everything dark or making everything light, to turning your image into an x-ray, to having absolutely no visible effect at all.
Let's get started with the basics.
Blending Modes control how one layer interacts with the layer below. That's it. Chances are good that you've already played around with blending by changing layer opacity. Remember how the layer became see-through and you saw what was on the layer below? That's blending. Instead of making the whole layer see-through, you can use Blend Modes to control exactly which areas (or colors, rather) of an image blend or mix with whatever is on the layer below, and which ones don't.
You can access Blending Modes in many places, including:
The Blending Mode menu is divided into several sections (illustrated below), according to what each mode does. They're pretty easy to memorize, as the first mode in each section is usually named after what it does. For example, Darken is the first mode in the section that will darken the underlying image. Remember, it's all about comparing two layers and then blending them together depending upon the colors found on each.
Using two intersecting circles, I'll illustrate what each mode does. In order for you to have a frame of reference, the first screen shot is Normal mode.
Nothing to see here! There is zero blending between the intersection of these two circles in Normal mode.
This mode turns semi-transparent pixels into a spattering of solids. Using two solid circles, the Dissolve mode creates no change because there aren't any semi-transparent pixels. However, if I use Layer Styles to add a drop shadow to the orange circle (which gives it some semi-transparent pixels to affect) and then change the Drop Shadow's Blending Mode to Dissolve, you can clearly see its effect.
What used to be see-through (the drop shadow) has been turned into a solid spray of pixels. Just to be clear, I did not change the Blending Mode in the Layers palette, I changed it in the Layer Style dialog box because that's where I created the drop shadow.
Honestly, I can't think of any practical uses for Dissolve mode. If you can, drop me an email.
The modes in this section have the power to make intersecting areas darker. Using the blue and orange circles as an example, the intersecting area darkened.
Photoshop compared the colors of the top layer (the orange circle--a combination of red, green, and blue because I'm working in RGB color space), to the colors on the layer below (the blue circle--yet a different combination of red, green, and blue) and kept only the darkest shades where the two layers intersect. Basically, any colors on the top layer which are darker than what's below will remain, and any colors which are lighter than what's on the layer below will disappear. Using two fairly dark shapes doesn't illustrate this mode's power, so let's give it a spin in the more practical realm of combining two photos.
For example, to combine the images below you might be tempted to select and then delete (or mask) the white background of the crazy man, then place the sunburst on a layer below him. That would work, but a faster method would be to use Blending Modes instead.
Since the starburst image is darker than the background of the crazy man image (which is where I want the starburst to end up), I can place the starburst at the top of the layers stack and change its Blending Mode to Darken. Thus combining the two images perfectly in one fell swoop:
Since the crazy man's right cheek and hand are lighter than the sunburst background, those areas of color remained. To fix it, simply add a layer mask to the sunburst layer and paint those areas with black (because in the realm of the layer mask, painting with black hides).
Here's the final result with the layer mask circled:
Hopefully a little lightbulb just came on for you. As you can see, it's worth spending some time getting to know Blending Modes and understanding how they work. Instead of having to create a selection around this dude's hair in order for the background to blend perfectly, Photoshop did all the work for you. That's what I call working smarter instead of harder!
That's all for now, but check back next week for more on Blending Modes. May the creative force be with you!