Blending Modes define how a layer affects whatever is below it, and it's an important feature that you are likely to use on daily basis.
We already know that layers in Photoshop can have transparency (actually in Photoshop we set it’s Opacity, which is reverse of transparency). One equally important, but less known, property of a layer is its blending mode.
Blending mode defines how the layer will “blend together” with the layer below it.
Let’s open house.psd that you’ve (hopefully) created in Sketching With Rhino tutorial. You can also download the file here.
Let’s turn off Color Balance, and People, and open the House layer group. You’ll see a layer called “Darkent Top”.
Take a look at where it puts “Multiply“. This is this layer’s blending mode, and here’s how the image looks:
Actually, let’s just increase the layer opacity to 100% so we can see fully the effect. So we have a sort of gradient that darkens the top of the image 100%, to full black and then towards the bottom the darkening effect is decreasing until it’s completely gone.
Change the layer blending mode to normal (1), and you’ll see it’s a simple black>white gradient, and that nothing is actually transparent about that layer (except the layer mask it “inherits” from the layer group “House” it’s located in). In fact, this black-white gradient is exactly what we see in the layer thumbnail (2). Also, let’s turn off Floor Shine, so that it doesn’t confuses us:
Now let’s see the 3 most typical blending layers that you will use on day-to-day basis:
Multiply blend mode will darken the layers below it, in such way that the darker our pixels are, the more they will darken the ones below it. White pixels have no effect (no darkening at all). Black pixels will darken 100% (to black).
You want to use multiply layer when you want to add shade or shadows to the layer below it.
Let’s look side-by-side how layer looks in “normal” and in “multiply” blending mode:
Screen works exactly the opposite of multiply: it will brighten up the layers below it.
White pixels will brighten up the layers behind 100% (to white), while black pixels will have no effect.
You’ll want to use Screen blending mode to add lighting to your image.
Overlay is probably the most versatile of all blend modes, because it works as both multiply and screen at the same time:
dark pixels (everything below 50% grey) will darken the image behind,
light pixels (everything above 50% grey) will lit it up
and 50% grey will have no effect.
You will use overlay for many, many things, including:
Using overlay will usually add contrast to the image:
As we’ve seen in the original image, by reducing Opacity of or “multiply” layer (to 47%), we reduced the darkening effect it has on the image:
Yes, of course, you can use color too. Let’s see what would happen if we did this kind of gradient, and then applied Multiply, Screen and Overlay:
What we see is that Overlay blending mode using colors can help use “colorize” the image to get some very interesting effects.
In fact, I very often used this trick, especially to “even out” the night images. For example, the following image was made by having an “overlay blending” layer with gradient that goes from blue to orange (see example). This intensified the blue colors in the upper “darker” portions of the image, and warm oranges and yellows in the brighter “bottom” part of the image.
Same principle was used to make a contrast between the “blue” ceiling and the “yellow” field and spectactors here, by having a layer painted with cyan and yellow and making it an “overlay”:
This particular case uses the cyan to black gradient with “Screen” blending mode, to emphasise the perspective:
Another example, using Screen blending mode to add “rain drops” to the scene:
So yes, try out different blending modes in action, and you’ll soon get the feeling of when to use which one!