If there's one thing that Photoshop has an abundance of, it's the selection tool. In Photoshop, there are at least half a dozen different ways to select things, and this tutorial will teach you the ins and outs of each way.
Learning to Use the Selection Tool in Photoshop
If you've ever needed to select something in one of your projects, I'm sure you've defaulted to using the selection tool in Photoshop. But wait... What does that even mean? Which selection tool were you using? Were you using it correctly? Was there a better option? Believe it or not, Photoshop has several different types of selection tools, and each one has a situation or two in which it is extremely useful, and several where it isn't. With this article, I hope to sort out the different types of selection tools and tricks, as well as teach you why you need to use them, when you need to use them, and how you can use them more effectively!
How Photoshop Handles Selections
Selecting something in Photoshop might seem like an extremely simple process, but you'll be surprised to find out that there really is a bit of complexity behind the whole thing. So how does Photoshop handle selections anyway? Well, that depends on the tool, but generally it handles it one of two ways.
The first way is selecting on a color-basis. With tools like the Magic Wand, and in newer versions of Photoshop, the Quick Selection Tool and Magnetic Selection Tool, Photoshop will select based on color. These ways are also heavily selected by opacity. Photoshop has 256 levels of opacity, generally defined by grey-scale. This means that pixels are semi-transparent will only be semi-selected. If you try to fill in a semi-selected pixel with the brush tool or paint bucket tool, they will only be partially filled.
Second is user-defined selection. For most other tools, such as the lasso tools and shape marquees, the user defines a specific area by clicking or clicking and dragging. These are useful for selecting large elements in Photoshop, either to move them, delete them, or provide a boundary when working in a certain area.
Basics Selection Commands - SHIFT, ALT, CTRL (CMD for Mac Users) Modifiers
Holding down SHIFT after you have created a selection will allow you to add another selection without deselecting your first. Holding down ALT will allow you to remove part or all of a selection you have already created. Holding SHIFT and ALT at the same time will allow you to create a new selection that intersects something already on screen. Holding down CTRL/CMD after you have created a selection will allow you to access a quick Move Tool shortcut, allowing you to pick up and move whatever is inside of your selection.
Shape Marquees (M)
Chances are, this is one of the most people are familiar with. There are four different kinds of shape marquees. A rectangular marquee, an elliptical marquee, and two one pixel line selection tools (one horizontal, one vertical.) Now, I myself have never found any real use for the one pixel line selection tools, but these work by selecting a line the whole way across your document one pixel either in width or height. The rectangular and circular marquees, however, are created by clicking and dragging to any size the user wants. Holding down SHIFT while clicking and dragging will constrain your selections either a circle or square. Holding down ALT will allow you to draw your circle from the center. CTRL/CMD has no effect. The shape marquee tools work very well for setting up boundaries that you can work within, or selecting large basic elements within a project.
Magic Wand Tool and Quick Selection Tool
The Magic Wand tool works by selecting a color or a color range of pixels. How much leeway you give it - by changing up the tolerance - will define how far Photoshop is willing to stray from the pixel you click on. If you click on a pixel of pure red with a tolerance of 1 with the Magic Selection Tool, it's going to only select colors extremely close to pure red. If you click on that same pixel with a threshold of 75, it will select pixels that are in the red spectrum, but not necessarily just red. Oranges, purples, and even browns might be selected with this tolerance. By default, Photoshop's tolerance level is 32. This tool is perfectly geared for recoloring parts of images by selecting the color you wish to change, and then using the hue/saturation sliders to change it.
The Quick Selection Tool works on a similar concept as the Magic Wand Tool, however you can control this one a little better by dragging a simple brush through the part you want to select. The marquee line will "snap" to the parts it thinks you want, and usually does a pretty good job. This is absolutely fantastic for selecting things that have a great deal of contrast from their surroundings. However, if you're doing an image that is mostly a single color, you may want to look elsewhere.
The Lasso Tool, Polygonal Lasso Tool, and Magnetic Lasso Tool
The Lasso tools are created to give a user a little more control over exactly what they're selecting. The basic lasso tool is a freehand tool that you click and drag around the object you want to select. Then, when you release your mouse button, a selection is formed.
The Polygonal Lasso Tool works on the same concept as the regular Lasso tool, only instead of being free-form, as you click it will form a straight line from one point to the next. Holding down SHIFT as you do this will constrain your angles to 45 degree increments. This is useful for when you need a little more control.
The magnetic lasso tool combines color-selecting and user-selection into a fairly functional tool. You click to start the magnetic lasso, which then clings to areas where there is a high contrast between colors. This is incredibly useful for removing an element out of a photograph or graphics design to be used elsewhere. For more on working with Lasso Tools, see the article "Learn How to Use Photoshop's Lasso Tools."
Other types of selections:
Pressing CTRL+A (CMD+A for Mac users) will select your entire canvas. This is particularly useful for adding boarders. Clicking on a layer thumbnail while pressing CTRL (CMD) will select all of the occupied pixels. This is the perfect solution to trying to select a lot of objects on screen without having to do it by hand.
Graphics were made by Amber Neely.