Selection tools
in Photoshop

Today we will be working with the different selection tools in the Photoshop Toolbox. Each tools is suited to a particular type of selection situation. The selection tools are located at the top of the toolbar.

In each section of this lesson, please save the image to your desktop, by right-clicking on it in the browser window and choosing Save Picture As. This way, you will have a local version to practice on.

Marquee tools

You will already be familiar with the rectangular marquee tool, but there are other options, which you can discover by clicking and holding on the little black triangle at the bottom right of the marquee tools button:

The elliptical marquee tool, as the name suggests, allows you to select an elliptical area of an image. To constrain the marquee to a circle, just hold down the SHIFT key.

Imagine a situation where someone in the picture has refused to give consent for their image to be included on a web site. By selecting them with the elliptical marquee tool, we could apply a filter from the Filter menu to obscure their face.

Alternatively, imagine a situation where you want to focus on one particular person in a group photograph. By selecting them with the elliptical marquee and then choosing Inverse from the Select menu, you can now apply an effect such as reducing brightness or contrast on the rest of the image so that just the person you want to focus on stands out.

Practice selecting one person with the elliptical marquee tool and applying an effect or a filter on this image:

The Magic Wand

The magic wand tool enables you to select an area of an image that is of the same or similar colour.

You can set a Tolerance for the Magic Wand - the smaller the tolerance, the more precise the magic wand will be about finding areas of similar colour. A bigger tolerance will allow you to pick up more areas that are broadly similar.

You can also choose whether your selection has to be Contiguous or not. If Contiguous is checked, then the Wand will only pick up areas of similar colour that are connected to each other. If Contiguous is not checked, the Magic Wand will pick up all areas of that colour within the image, within the set Tolerance, whether they are connected or not.

You can also choose whether the selection's edges should be Anti-aliased or not. If Anti-alias is checked, the edges of the selection will be dithered so that there is a smooth transition between the selection and the surrounding image.

Practice selecting areas of similar colour with the Magic Wand on the image below. Not the effect of changing the Tolerance, Contiguous and Anti-aliased settings.

The lasso tool

The lasso tools help you to select irregular-shaped areas of an image. You can choose different types of lasso tools, depending on your requirements, by clicking and holding on the little black triangle at the bottom right of the lasso tools button.

The Lasso Tool effectively allows you to select an area of the image by drawing around it freehand.

The Polygonal Lasso Tool allows you to select more precisely by clicking on the image to place nodes that mark the edges of your selection. For example, if you wanted to just select the socks in the image below, it would be easier to do this using the polygonal lasso tool, because drawing your selection freehand through the narrow gap between the socks and the coat could be quite tricky.

Practice using these two selection tools on the image below.

The Magnetic Lasso Tool is very suited to selecting areas of an image that have a clearly defined edge, such as the hat in the image below. The Magnetic Lasso Tool works in a similar way to the Polygonal Lasso Tool, except that it "guesses" where you want to place the nodes of the selection.

This is an extremely useful selection tool, but can be a bit fiddly to use at first, so practice by selecting the hat in the image below.

Practical applications of the selection tools

In practice, you will probably use a combination of all of these selection tools when editing an image. For example, to combine the two images below to create the final image, one would first have to separate the monument from the background in the first image, using whatever selection tools work best. If you begin the task by deleting as much of the rest of the image as possible, using the selection tools to select the background piece by piece first, then you will end up with the monument on a solid colour background. It is then easy to use the Magic Wand to select the whole of the background, and by then choosing Inverse from the Select menu, the monument is then selected in isolation so that you can copy it and paste it onto the sky image to make the third image.

Have a go at making the composite image.