Some times you may want to make selections that do not conform to standard shapes. You may want to edit some oddly formed object in your image, or you may want to isolate a region with curves and unusual angles. To do this kind of work, you can take advantage of the lasso tools.

 

 

To use the basic lasso tool, select it from the tool box or from its tool group if it is not visible in the toolbox. When you drag your mouse over the image, a line will be drawn that follows the path of your mouse pointer. You can basically draw a free form selection around any region of the image you wish. To complete the selection, make sure that your mouse pointer ends up at the place that you started from. If you do not, Photoshop will automatically draw a straight line from your ending point to the point you started from to close off the section. The path you draw with your mouse must be closed (a loop so to speak) to create a selection. When you release your left mouse button (stop dragging) the selection will be complete.

 

In this image, the lasso tool was used to draw a selection around the neck tie. If you look closely you can see the dashed border.

 

 

As before, you can place your mouse pointer inside the selection and move it around by dragging. You can also right click on the image to reveal a menu of options for working with your selection.

 

You can use the polygonal lasso tool to make selections in the shape of polygons by drawing a series of straight lines (joined at anchor points) with your mouse. First, select the tool from the toolbox, and then single click at the starting point of your selection. Click on another area of the image, and you will see a line joining the first anchor point to this second anchor point. Continue to add these points until there is a series of lines enclosing your selection. As with the other selection tools, a selection must be closed to be complete.

 

 

In this image, the polygonal lasso tool was used to build a selection from straight lines, isolating the jacket collar.

 

You can put your mouse pointer inside the selection to drag and drop it around the image canvas if you wish. As with the other selection tools, right clicking on the image will reveal several options for working with selections.

 

If you hold down the Alt key when using the polygonal lasso, it will behave like the basic lasso, and you can draw freeform selections. If you hold the Delete key after drawing a free form shape with the polygonal lasso, the free form line you drew will slowly disappear.

If you press the delete key after making a polygonal selection with anchor points, the most recently created anchor point before the current mouse pointer location will disappear and the selection will adjust to the next anchor point. Each time you press delete, anchor points will be removed in this manner.

 

The final lasso tool, the magnetic lasso, can be used in the same way as the polygonal lasso. However, rather than drawing straight lines, the magnetic lasso will join anchor points with lines that adhere or conform to edges in the image. Lines separating contrasting areas of an image, or the image borders themselves, are examples of edges that the magnetic lasso can adhere to.

 

To use the magnetic lasso, select it from the toolbox, and click on the image at the starting point for your selection. As you move your mouse pointer towards the next place that you would like to place an anchor point, you will see the magnetic lasso adhere to curves or lines between the points. To get more control over the magnetic lasso, click to leave anchor points frequently.

 

When you are finished drawing your path you may see a small circle if you end up close enough to your starting point. If you see this circle, single clicking your mouse will complete the selection. If you are farther away from your starting point, double click to close and create the selection.

 

If you are patient, and place frequent anchor points, the magnetic lasso can be used to make very elaborate selections. If you place your mouse pointer inside the selection, you can drag the selection around the image canvas. If you right click on the image, a menu of selection options will appear.

 

 

The selection in this image was created with the magnetic lasso. Remember, you can get more control over the behaviour of the magnetic lasso by carefully placing your anchor points.

 

 

If you hold down the Alt key while you are using the magnetic lasso, you can drag your mouse pointer to draw freeform selections like the basic lasso. If you hold down the Alt key and click your mouse button, the magnetic lasso will behave like the polygonal lasso (lines between anchor points will not adhere to contrast edges).

 

There are lots of options available in the options bar for the magnetic lasso.

 

 

In the box labelled Width, you can specify a number that effects what distance you can be from an edge and still have the lasso adhere to it. The figure in the Edge Contrast box helps you to control what level of contrast the lasso will perceive as an edge. As this number increases, the lasso gets less sensitive (more contrast is required for an edge). With the Frequency box, you can control how frequently the lasso creates anchor points.