To cut out images in Illustrator involves a technique called a Clipping Mask. First we need to place an appropriate image involving a few simple steps. From the File drop down menu on the top right of the interface, we select Place, upon which a dialog box opens offering several options. We now browse to where our image is saved. Several types of file format can be placed into Illustrator, but probably the most common one would be the JPEG format, used for importing pixel-based bitmap images. We can then trace around the image, as in the case of garment design. Or we may wish to use the Image Trace function to convert the image easily into vector-based artwork.
Bitmap and vector-based imagery differ in that that the former is usually a photograph where the image is stored as a series of small coloured boxes called pixels. The software stores each pixel data as a number for colour and brightness. In the latter case of vector imagery, often used for illustrations, logos or text, the data is made up of mathematically calculated lines and curves. And while Photoshop mostly deals with pixel-based imagery Illustrator is first and foremost a vector program.
Bitmap imagery can be imported (or placed) into Illustrator. Once we have browsed to our image the Place box offers a few options. If we wish to trace around an image we should check the Template box which will introduce the image as a semi-transparent layer and create a blank tracing layer on top. This image layer can then be unlocked and rescaled if necessary.
If the image is to be saved as a Symbol for later use, we should untick the Link check box. And it’s best to embed the image in this manner if the file will be sent on to another user. Next we hit OK and the image appears at the centre of the artboard.
If we wish to cut away the image’s background first choose the Pen tool to trace around the object. Next we select both the photograph and our drawn path, and go to the Object menu to select Clipping Path, and Make. The clipping mask can later be adjusted using the Direct Selection tool, or by right-clicking and selecting Release Clipping Path. Clipping Masks are used in two contexts: either to cut away parts of an imported image, or to clean up the Illustrator artwork, for example a border with rounded corners.
In the former example, select File and Place, then browse to the photograph you wish to cut around. We use the Pen tool to first draw around the shape. Initially this can be as accurate as you wish. We then modify the anchor points using the Direct Selection tool and the Add Anchor Point, Delete Anchor Point, and the Anchor Point tools.
We then select both image and clipping path with the Selection tool, right-click and choose Make Clipping Mask whereupon the image will be cut out. If we wish to adjust the result later, we can right-click again on the object and choose Release Clipping Mask.
Tom Gillan has been training Indesign to corporate clients in Sydney for seven years. You can learn more about Adobe Illustrator Courses at http://www.designworkshopsydney.com.au/adobe-illustrator-courses/.