Welcome to Photoshop selections part 2. If you didn't followed Photoshop Selections Part 1 then do so before reading this tutorial.
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Quick Selection and Magic Wand Tools
The next selection tools on the toolbar are the Quick Selection and Magic Wand. Let's talk Quick Selection first. Think of it as a brush not for painting but for selecting. You can change the brush size to select more or lower the brush size to select less.
You can see in the image below how the Quick Selection icon even resembles a brush. The brush with the + sign is used to add to the selection and the brush with the – sign is used to subtract from the selection. If you check Sample All Layers then it will make selections based not only on the actual layer but in conformity with all the layers. Auto-Enhance will make your selection edges better and Refine Edge will open the Refine Edge window.
How it works? If you brush over an area then Photoshop uses an algorithm to determine where the closest edges are and snap to them. You can see in the image below by the red how I quickly selected the sky by dragging (or painting) with the Quick Selection tool in the red encircled area. Notice how the selection automatically snapped to edges. Notice that the selection didn't snap around the edges of the Statue of Liberty. That's because the color of the statue it is close to the color of the sky (blue-cyan) but it snapped around the buildings below the statue because they are a different color and have a pronounced edge. This tool it is good for quick and dirty working and when you are in a hurry. I find myself using this tool when I composite scenes from different images and I just want to see how an object from an image would fit into my composite scene without the time required to make a refined, precise selection. Experiment with it on different images and get the "feel" of how this tool works. One quick tip worth mentioning it is that you can press the Alt key and drag with the brush to subtract from the current selection.
Next is the Magic Wand tool. The Magic Wand tool works like this: you click somewhere in the image and an area is selected based on the settings of the Magic Wand, the area you clicked on and the closest edges. You can see in the image the red encircled area is where I clicked once with the Magic Wand tool.
Notice how it selected an area and it snapped around the edges of the Statue of Liberty.
Let's take a look at the settings available for the Magic Wand tool. The 4 icons with squares at the left are in order from left to right: New selection, Add to selection, Subtract from selection and Intersect with selection. When one of these icons it is activated (like the New selection icon is activated in the image below) your further clicks with the Magic Wand tool act differently on the current selection. With Subtract from selection activated then you will be subtracting from the selection, with Add to selection you will be adding to the current selection and with the Intersect with selection you will have an intersection between the current selection and the area you just selected with the Magic Wand tool. You can also use shortcut keys to replicate the above behaviors. While clicking with the Magic Wand tool hold Alt to subtract, Shift to add and Alt + Shift to intersect.
The Magic Wand tool works like this: when click you somewhere on the image it will select a contiguous area of pixels based on the Tolerance setting. The Tolerance values range from 0 to 255. These values are familiar, aren't they? We know from this previous tutorial that these numbers represent the luminosity values a pixel can have. Let's say that you have a Tolerance of 10 and you click on a pixel with a luminosity value of 88. The Magic Wand tool will select all adjacent pixels with values that are between 98 (88 + 10) and 78 (88 – 10). If Contiguous is unchecked then it will select all the pixels in the image with values between 98 and 78. The Anti-alias checkbox makes your selection edges smoother. Sample All Layers and Refine Edge work the same way as with Quick Selection.
Let's take a look at a practical example. I clicked in the red encircled area with the Magic Wand tool. The Tolerance setting was 50. Notice how the selection snapped around the edges of the Statue of Liberty. That's because the luminosity level of the sky is about 170 and the luminosity level of the Statue is 70. Because I clicked a pixel with a luminosity level of 170 it selected all the contiguous pixels within 220 (170 + 50) and 120 (170 -50) because the Statue of Liberty has a luminosity level of 70 it was not selected.
Color Range
Let's move on to yet another selection tool Photoshop provides, namely the Color Range. You can access the Color Range Dialog box by choosing Select > Color Range. It works similarly with the Magic Wand tool – it selects an area based on the clicked area luminosity value. It also has a preview black and white version of the image showing the selected areas. White shows the selected areas, black the unselected areas and gray the partially selected areas. You can click on the small black and white preview image or you can click on the actual image. Localized Color Clusters is similar to the Contiguous checkbox for the Magic Wand tool. Fuzziness and Range expand or contract the selected areas and the little pen icons with the + and – sign stand for Add to selection and Subtract from selection (you can also hold Alt for subtract and Shift for Add). You can get familiar with this window by giving it a try. Play with the Fuzziness and Range sliders, click on different parts of the image and notice how the selection changes. Remember, in the small black and white preview image white stands for selected areas, black for unselected areas and gray for partially selected areas.
I use this tool for applying Image Adjustments to different parts of the image. Let's say I want to change the color of the sea. I can make an approximate selection with the Color Range (look below) and then I can apply an Image Adjustment of my choice (Curves, Hue/Saturation, etc…).
In this case I used a Hue/Saturation adjustment to change the hue of the selected area (Image > Adjustments > Hue/Saturation).
As I said before, just reading about this stuff isn't going to teach you a great deal. Practice and experiment to learn how to use these tools.
Learn How to Select
Now it's time to show the pro selection method. It is a bit more complex and it involves the use of the Pen tool but the results are worth the effort.
What is the Pen Tool? The Pen Tool creates vector shapes using Bezier Curves. Vectors are pixel independent and are rendered using mathematical formulas. I will not get into explaining vectors and Bezier Curves but I will give you a quick and dirty guide for using the Pen Tool to create amazing selections. The process of creating selections with the Pen Tool has 2 major stages:
1.Use the Pen Tool to create vector outlines.
2.Convert vector outlines to a selection.
Firstly select the Pen Tool by pressing P. Make sure option Paths is selected. You can start creating straight vector outlines by simply clicking in different places. The last click should overlap the first starting point to obtain an outlined vector shape. If you don't want to enclose the outline simply Ctrl-click anywhere at any stage of drawing with the Pen Tool to finish drawing the vector path. The term "path" and "vector outline" are roughly equivalent and I use them interchangeably. "Vector outline" suggests an enclosed area while "path" is more of a freeform line. The little squares in the image below are called Anchor Points. When you click with the Pen tool you create an Anchor Point. If you click again in a different position you create a new Anchor Point and a path that connects the two Anchor Points. That's the bread and butter of paths: Anchor Points connected by paths.
To create curved paths click once anywhere on the image and then click and drag to some other point. When you do that notice that the straight lines become a curve and its curvature is in the opposite direction to the dragging. The more you drag the more pronounced the curve. Notice the new elements: Handles. You can drag the handles after you have created the path to modify the curvature of the path.
In the image below I clicked and dragged again to continue my path.
And finally I clicked on the starting point to enclose the path.
T o transform this path into a selection simply press Ctrl + Enter. This may seem like a lot of overkill for a simple selection. Believe me, it is not. This is a very simple and limited example of the Pen Tool and is for demonstration purposes only. You can create precise and intricate paths and convert those paths into selections. This comes in handy when you are dealing with objects that have a color close to the background color, making the use of the common selection tools (Magic Wand, Quick Selection) impractical. Heck, even this simple example below is hard to replicate using the simple selection tools. I dare you to create the perfect teardrop form shown below with the Lasso Tool. You will find out that it is not an easy task.
Conclusion
This concludes the Photoshop Selection tutorial series. This is just an introduction to the wonderful world of selections and it barely scratches the surface of the more advanced capabilities of Photoshop regarding selections (Channels and Layer Masks) but I hoped it served its purpose and made basic selections easier for you.
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