Photoshop's Selection Tool

Photoshop's Selection Tool
The selection tool (Rectangular Marquee) is one of the most important tools in Adobe Photoshop. However, most people don’t realize that it can be used for much more than drawing a rectangle, square or a circle. In this article, we will review some new techniques that you can use with this tool.

Now, most of you probably already know how to use this tool. You click on any area in the canvas, you drag your mouse and the desirable shape is formed. But, if you notice, there’s bar at the top that gives you a few more options. Those options are Normal, Fixed Aspect Ratio and Fixed Size.

The Normal option is the one we use the most. It lets you draw any shape of any size and proportion, whereas the Fixed Aspect Ratio option is more precise. You can enter the ratio you want in the width and height fields, which will enable the selection to be in the ratio proportionate to the values you specified. Say for example, you specified the width to be 100 and the height to be 200. Now, whatever shape you drag it to will always be proportionate to this value, like 100,200 or 200,400, etc. You will not be able to draw, say a 500,500.

The fixed size option is even more specific. You specify the value in the width and the height field and click on the canvas. From there, you will see a selection of the exact same size that you specified. For instance, if you specified the width as 400 and the height as 500, the selection you'll get after clicking will be exactly 400,500. You can’t modify that.




The selection tool can also be used in conjunction with the Alt and Shift keys to get even more options. The general rule is that the Alt key is used for subtraction and the Shift key for addition. Let’s see some examples that will help you understand this a little better.

Say you want to draw an L shape. Go ahead and draw a vertical rectangle. Now, press Shift and you will see a little plus sign next to the selection tool. While you keep holding down the Shift key, draw a horizontal rectangle adjacent to the vertical one and bingo, you have an L shape.

Similarly, say you want to make a rectangular D shape. Go ahead and make a regular rectangle, but without holding down any keys. Now, with the selection tool selected, press Alt and you will see a little minus sign next to the crosshair. With the Alt key still held down, make a smaller rectangle inside the one you drew earlier and voila, you have a D shape.




Selecting the appropriate button on the top left corner can also do the addition and subtraction.




This cool trick can also be used on layers, especially overlapping layers. To select everything on a layer, go to the layer’s palette and hit Ctrl + a Left Click on the layer. The whole layer will then be selected.

Now, if there’s a second layer under it and you want to subtract the overlapping portion of that second layer, just press Ctrl + Alt and left click that second layer. The part of the second layer that was under your original layer is now subtracted from the selection.




So, what if you want to add that second layer to the original selection? Yep, you guessed it. Press and hold down Ctrl + Shift and left click that layer. You will then see both the layers being selected.




With the first layer selected and using Ctrl + Click, what if you use Ctrl + Alt + Shift + Left Click the second layer? Go ahead and try it, you will be surprised!

There’s one more thing that I find very handy. It’s the ability to inverse a selection on a layer. If you select an object on a layer or the whole layer itself and press Ctrl + Shift + I, it will invert the selection. Try it out. It can come in very handy in a lot of situations.

The last thing I’d like to talk about is the Select menu, which is right on top on the menu bar. This menu has a few very handy options that I’d like to bring to everyone’s attention. Look under the Select, Modifymenu and you will see four options. I’ll explain them one by one.




Border: This one is rather self-explanatory. It lets you draw a border around your selection.

Smooth: This function smoothes (rounds up) the corner of your selection, based on the radius value that you enter. Try different values to see what kind of different effects it gives you.

Expand: With this function, you expand the boundary of your selection that is proportional to the value you specified. Think concentric circles.

Contract: This one is the exact opposite of expand. This contracts the selection by the amount of the value you specified. Simple enough, right?

There’s one more option in the Select menu and that is Select, Feather. This one is a bit tough to explain. You have to do it to understand it. So, go ahead and mess around with this a bit. You will find yourself using this a lot if you like these kinds of effects. Also, remember that if you have made a complex selection and would like to use it for another document, you should save it. Go to Select, Save Selection to save it and similarly, go to Select, Load Selection to load it up.



So, there you have it. You didn’t think you could do so much with just a little selection tool, did you? Well, now that you know the tricks, what are you waiting for? Fire up your Photoshop and put that "Do Not Disturb" sign on the door. Have fun!

Posted in: How to, Photoshop, Tips and Tricks