"Selective Color"is a type of post processing that creates black and white images, with some elements remaining in color, like the yellow flower, below.
While the technique is a bit over-used, it can be appropriate in some cases, and is a good tool to have in your bag of tricks. A small dab of color in a grayscale photo instantly grabs the viewer's attention, which explains why black and white portraits with colorful eyes are so popular. The technique can help tame a colorful and distracting background, as in the example to the right. There were bright red and yellow spots in the bokeh ( out of focus background ) that competed with the flower for attention.
Sometimes the reverse is true; a photo works very well in color, but has a minor piece ( say, a leaf in the background ) that you'd like to de-emphasize.
This article will demonstrate how to create selective color images using Photoshop. The instructions below assume intermediate Photoshop knowledge: working with selections, layers, and masks. These skills aren't particularly difficult, though, and you can learn what you'll need for the task at hand from this article.
At left is the photo we'll work on in this tutorial; the skills translate easily to anything in your porfolio.
The background is colorful and saturated, drawing attention away from the sphynx moth. Although darkening the background would be just as effective, this gives us a chance to explore how selective color photos are made.
At this point, you can pull the file at left into Photoshop to follow along with the tutorial, or you can use one of your own.
Step #1 is to build a selection around the areas you want to leave in color. For this tutorial, we're going to leave the pink in the wings and the purple in the flower the moth is interested in, and turn everything else black and white.
The selection doesn't have to be perfect, but the closer it is, the less work you'll have later. Still, it's much better to err on the side of caution, and select too many pixels rather than too few. Let's have a look at some of the different choices for selecting the colors we want to keep:
Chances are you'll wind up using some combination of the three selection techniques. With all of them, you can hold down the shift key to add to the selection, or alt to remove from it.
Once you have the color you want to preserve selected, flatten the image if you haven't already done so, then go into the Layer menu, the New submenu, and select Layer Via Copy. ( Ctrl + J in Windows )
Now select the background layer, and turn it black and white. Converting from RGB to Grayscale won't work, because that applies to the entire image, not just the current layer. Use the channel mixer tool instead. ( For more info, see: Digital Black and White in Photoshop. )
If you built a perfect selection, then your job is done ... but most of the time, there's a little clean up work to do; this is where masking comes in.
Because the pink in the wings and the purple in in the flower stand out so much from their neighbors, the wand selection tool was able to do what I needed easily in this case. Let's look at a more hands-on approach for difficult images.
Masking is one of the more powerful features in Photoshop, allowing you to make complex edits to some parts of an image but not others in a very specific way. We'll assume that selecting with the wand tool and by color didn't work, so we resorted to the lasso tool, and need to clean things up a bit.
In this case, we want the beak to be in color, but the rest of the image in black and white. I gave myself a comfortable margin around the beak, but at this point the image looks terrible. Yellow from the feathers is left behind, and looks out of place in an otherwise B/W image when the rest of the feathers are white.
You can either spend time building the selection, or spend time masking extra pixels away.
Click the white circular button with a gray background, at the bottom of the Layers Palette ( highlighted in red in the screen shot at right ). This builds a layer mask, and creates the white rectangle next to the layer's thumbnail. The rectangle shows the mask placed over the layer, which is empty at this point. Parts of it will fill in when we remove the yellow from the feathers around the beak.
Now use the brush tool, and zoom in to 100 % view. With the brush color set to black, paint out as much yellow as you can without also painting over the beak. The color will disappear as you go, revealing the black and white version underneath. It can be helpful to do parts of this with the background layer invisible.
In general, hard-edged brushes work best. You probably want the opacity set to 100 % for the layer you're trying to remove, and you'll want to change between several zoom levels pretty often throughout the process.
If you make a mistake, change the brush color to white, and paint over the area; the color will reappear.
The process isn't very complicated; it's just time consuming. You'll have to find your own balance between how much you select, and how much you need to mask away later.
The result, while not terribly interesting, is below.
Selective color is an easy effect to apply, but it can take a lot of time to get natural looking results. Subjects that lend themselves to the wand tool are much easier to work with.
Three photos are used in this article; a yellow flower from China Beach, San Francisco; a sphyinx moth in Zion National Park, Utah, and a parakeet named Vladimir Putin because of the way he beat up his parakeet roommate, in my home in Seattle.