Attracting with the Magnetic Lasso Tool in Photoshop

The newest member of the lasso tool trio is the Magnetic Lasso, which I admit can be kind of tricky to use and sometimes even downright obstinate. The Magnetic Lasso tool works by analyzing the colors of the pixels between the elements in the foreground and the elements in the background. Then it snaps to the edge between the elements, as if the edge had a magnetic pull.

The Magnetic Lasso tool performs best when your image has a lot of contrast between the foreground and background elements — for example, a dark mountain range against a light sky or a shadow against a stucco wall.

The Magnetic Lasso tool also has some unique settings, which you can adjust in the Options bar, to tame its behavior. I cover those settings in the next section, “Adjusting the Magnetic Lasso options.” For now, follow these steps to use the tool:

1. Select the Magnetic Lasso tool from the Toolbox.
You can also use the keyboard shortcut:
Press the L key and then press Shift+L until you get the Magnetic Lasso tool. The tool looks like a straight-sided lasso with a little magnet on it.

2. Click on the edge of the object you want to select.
You can start anywhere; just be sure to click on the edge between the element you want and the background you don’t want.

3. Move your cursor around the object, without clicking.
The Magnetic Lasso tool creates a selection line similar to the other Lasso tools. It also adds little squares called points along that selection line. These points pin down the selection line the way you might section off an area of your yard with ropes and stakes.
-->If the Magnetic Lasso tool starts veering off the edge of your object, back up your mouse and click to force a point down on the line.
-->If the Magnetic Lasso tool adds a point where you don’t want one, simply press your Backspace (Delete on a Mac) key to delete it.

4. Continue moving your mouse around the object; return to your starting point and release the mouse button to close the selection.
As with the Polygon Lasso tool, you see a small circle next to your cursor indicating that you’re at the correct place to close the selection. If you double-click, Photoshop closes the selection from where you doubleclicked to your starting point. The selection marquee appears when the selection is closed.