Precise Selections in PhotoShop

Posted: July 05, 2010

If you are someone who wants to know how to do perfect, surgically precise selections, there is a lot to learn. Here’s a few things to keep you busy while you’re perfecting your selection skills.

By Ben Willmore, www.digitalmastery.com

If you are someone who wants to know how to do perfect, surgically precise selections, there is a lot to learn. Here’s a few things to keep you busy while you’re perfecting your selection skills.

If you're using the Magic Wand tool on a layered image, you might find that it can only use the information of the currently active layer. You can turn on the Sample All Layers checkbox to allow the Magic Wand to work with all the information in the image (as if all the layers have been merged together).

If you are having trouble selecting an object because it is too similar to its background, then you might want to think about adding an Adjustment Layer (Layer>New Adjustment Layer). I often create a Hue/Saturation Adjustment Layer and increase the Saturation setting to exaggerate the colors in the image. Either that, or you could try to use Levels and pull in the upper left and right sliders to increase the contrast of the image. Then, once you've selected the object, you can always throw away the Adjustment Layer to get the image back to normal.

After you've made a selection, you can choose Select>Modify>Border to select an area centered on the marching ants. But, what if you'd rather select a border that is inside the marching ants instead of being centered on them? Well, try this; make a selection, type "Q" to turn on Quick Mask Mode, then choose Filter>Sketch>Photocopy. Adjust the Darkness setting to control how feathered the inner edge should appear, and adjust the Detail setting to control the width of the border.

When you use the Select>Color Range command, you might notice that too much of your image ends up being selected. So, before using that command, make a very generic selection of the area you'd like to change. This will force the Color Range command to only analyze the area that is already selected, which will result in a more accurate preview image because it will not contain the entire image (which is usually too small to be useful). You can also hold Shift before choosing Color Range to add to an area that is already selected, or hold Option (Macintosh), Alt (Windows) to take away from the current selection.

You can Command-click (Mac), or Ctrl-click (Windows) on the Thumbnail image of a layer to select the contents of that layer. But if part of that layer extends beyond the document's bounds, then so will your selection. To limit the selection to the edge of your image, choose Select>Inverse twice.

If you're going to use a selection over and over again, then choose Select>Save Selection. To retrieve the selection later, choose Select>Load Selection. These "saved selections" will remain in your file as long as you use the Photoshop (.psd), or TIFF (.tif) file formats.

Once you've saved a selection within your document, you can quickly retrieve it by holding Option and Command (Mac), or Alt and Ctrl (Windows) and pressing a number on your keyboard (instead of choose Select>Load Selection). If you have an RGB image, then the first saved selection can be retrieved using the number 4. If you have a CMYK image, then start with 5. Then to load the second selection you've saved, just increase those numbers by one. For grayscale images, start with 2.

The Background Eraser and Extract command can be used to remove the background of an image. But if you'd rather end up with a selection instead of really deleting the background, try this; duplicate the layer you'd like to work on and use either the Background Eraser or the Extract command to get rid of the background (you might have to hide the duplicate image underneath in order to see what's going on). Now Command-click (Mac), or Ctrl-click (Windows) on the layer thumbnail you removed the background from. That should create a selection of the contents of that layer. Next, throw away that layer and make the duplicate layer active and you have a selection with the original background still intact.