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Computer Graphics Enhancing Photos with Adobe Photoshop – Level 1. What You’ll Learn…. Basic photo processing and enhancement techniques using Photoshop. Stuff You’ll Need…. Photoshop CS2, CS3 or CS4 Digital camera, digital photo or scanned image. ePortfolio Suggestions….
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Computer Graphics Enhancing Photos with Adobe Photoshop – Level 1
What You’ll Learn… • Basic photo processing and enhancement techniques using Photoshop Stuff You’ll Need… • Photoshop CS2, CS3 or CS4 • Digital camera, digital photo or scanned image
ePortfolio Suggestions… • Before you start, examine your image and describe how you plan to use Photoshop to improve it • Collect “screen grabs” as you go to document your work flow • Compare and contrast “bitmap” and “object-oriented” graphics. Give examples of each. When is it best to “paint”? When is it best to “draw”? • Create a “How to” tutorial for other learners on a Photoshop tool or technique you found particularly useful
What You Should Know… About Photoshop Adobe Photoshop is one of the most powerful computer graphics tools on the market. Since the release of version 1.0 in 1990, Photoshop has been at the very forefront of the computer graphics industry. Professional photographers, illustrators and graphic design artists all use Photoshop in their everyday work! While digital photo manipulation is an obvious application, Photoshop’s drawing, painting, digital filter and text features make it a popular tool for commercial art, graphic design and even original illustration. Ask anyone who’s ever used Photoshop and they will tell you that it’s features and capabilities are virtually “bottomless”. So much so, that even Photoshop masters will tell you they are constantly learning new techniques and capabilities. But don’t be intimidated! Once you begin to get familiar with Photoshop, you’ll find that most of its tools and features are really very easy to use. And, because Photoshop is used by so many professionals and serious hobbyists, you can find free online tutorials for almost anything!
What You Should Know… Drawing and Painting When using any computer graphics application, you should understand about bitmap graphics or “painting” applications, and object-oriented graphics or “drawing” applications. Like many computer graphics applications, Adobe Photoshop has tools to do both and you are likely to integrate both kinds of tools in many projects. Vector Graphics and Drawing In computer graphics an “object” is a graphic element that is drawn by the computer based on its assigned mathematical properties. The process of creating objects is also called vector graphics or object-oriented graphics.Objects are made up of graphic “primitives” such as lines, curves, circles and squares – each with properties such as size, position, etc. Because each object is drawn by the computer based on its mathematical properties, it’s easy to manipulate the object as a unit – moving it, or making it bigger for example.Architects frequently use object-oriented graphics programs (you may have heard of “CAD” which stands for computer-aided drawing). In CAD, among the properties you assign to a rectangle (representing a room, for example) is it’s dimension. Changing the size of a room is as simple as giving the computer new size instructions. It redraws the rectangle based on this new property.
What You Should Know… Drawing and Painting (continued) Bitmapped Graphics and Painting Bitmapped graphics are collections of points arranged in a pattern. These points are called “pixels” (short for picture element) and have properties of size, color and intensity (or brightness). A digital photograph is an example of a bitmapped image. If you zoom in very close, you’ll be able to see the square-shaped individual pixels (you’ve probably noticed that digital cameras are often advertised by their megapixels - a megapixel is one-million pixels). Find out the maximum image size on the SmartLab camera (it will look like ####X####) – multiply the two numbers and divide by 1 million – you now know the camera’s resolution in megapixels! Creating or modifying bitmapped graphics is called “painting”. In Photoshop, there are many, many tools that “paint” or modify pixels. Painting tools provide tons of creative flexibility because they modify an image pixel-by-pixel – the smallest possible element in any digital image. Unlike CAD though, there are no “objects” that can be changed as a unit. It’s a little like real painting. Photoshop offers some drawing tools as well. Plus, there are some very clever ways to use painting tools that combine the best of both worlds - allowing you modify groups of pixels all at once, selectively or even in layers. More on this later…
What You Should Know… Drawing and Painting (continued) • Here’s a quick exercise to help you understand the difference between bitmap and vector graphics. • Launch Photoshop and click New under the File pull-down menu. Create a new document 1000 pixels wide, 800 pixels tall at 72 pixels per inch. Set your background to white.
What You Should Know… Drawing and Painting (continued) • Select the elliptical marquee tool by clicking on it. • Place your cursor somewhere over your new document and click/drag it to select an elliptical shape (if you hold down the SHIFT key while you get a perfect circle). • Now Click the Edit pull-down menu and click Stroke. A dialog window will appear like the one pictured below. Set the width to 1 pixel and black as your color. Click O.K. to “paint” your circle with a 1 pixel black line. Press Control+D (Command+D on a Mac) to deselect the “marching ants” on your circle. Edit Menu Elliptical Marquee Tool Stroke Dialog Box Hold down the shift key while you click-and-drag the elliptical marquee tool to get a perfect circle
What You Should Know… Drawing and Painting (continued) • You’ve now painted a 1 pixel black circle using bitmap graphics. It should look like the circle on the left below • Now let’s draw a circle using vector graphics. Choose the ellipse tool by clicking on it on your tools palette. If there’s another shape tool there instead (like a rectangle), right-click it and a menu will appear where you can select the ellipse tool. Make sure “Paths” is selected in the Options Bar. Now draw another circle next to your first one by holding the shift key while you click-drag over your document. You should now have something that looks like this. Paths Option Ellipse Tool Painted Circle Drawn Circle
What You Should Know… Drawing and Painting (continued) • Let’s take a closer look. Select the zoom tool by clicking on it. Hold it over a spot somewhere between the two circles and click a few times to magnify your image. Did you notice how the bitmap circle begins to loose it’s definition while the vector-based circle stays well defined? As you zoom in you’re beginning to see the individual pixels that make up your painted circle. But since the drawn circle is an object it remains a well defined circle at any size. • Discuss these questions with your partner: • What are the advantages of painting? What about drawing? • Do you think architects would find drawing or painting more useful when designing a house? • What about graphic designers making a company logo that could be used for a large sign or small advertisement? • Is a digital photograph a bitmapped image or an object? Zoom Tool
Do It!Enhancing a Photograph Before we start on a photograph, let’s take a quick tour of the Photoshop CS3 workspace. There’s a lot there. But for now, let’s focus on just a few areas. You’ll use these pull-down menus to access photo enhancement and file handling features This is the history palette. As you work on an image, each step (up to a preset limit) will be recorded here so you can “go back in time” with a click of the mouse. This is the tool palette. You select a tool by clicking on it.
Do It!Enhancing a Photograph Depending which version of Photoshop you’re using, your workspace may look a little different than shown here. That’s okay, all recent versions of Photoshop basically function the same way. The workspace on the previous page is version CS3 while the one below is CS4. As you can see, they’re pretty similar. You may also find that the default workspace on your SmartLab computer is missing one or more of the panels or pallets you want to use. For example, the workspace below doesn’t show the “History” pallet, which is one of the most useful pallets and is discussed in this Learning Launcher tutorial. You can activate a pallet by clicking on it under the Window pull-down menu. Click here to activate the History pallet
Do It!Enhancing a Photograph To begin, you’ll need a photograph to work on. You can take a picture of something in the SmartLab (like your partner), bring a photo from home, or download an image (if you download an image from the internet, make sure it is fairly high resolution - 1000x1000 pixels or more). Before you begin to work on your image, let’s look at a sample image. Here’s a picture of a kid in a SmartLab. Take a careful look. What do you see that could be improved? There’s no right or wrong here, it’s all up to your judgment and taste. Make a short list, then proceed to the next slide.
Do It!Enhancing a Photograph Here’s some things we think could be improved This picture looks a little dull overall. A little more contrast will help Let’s see if we can remove these blemishes This girl’s elbow is sticking into the picture. His skin tone looks a little too red. The color balance on this picture could use some work. What’s up with the hand stamp? How does your list compare with ours?
Do It!Enhancing a Photograph Watch this tutorial video to learn how to digitally enhance this photo. And if your SmartLab has Photoshop CS4, check out this video too and see what’s changed! Tutorial Video: Enhancing Photos in Photoshop Tutorial Video: CS4 Update Before After
Do It!Enhancing a Photograph Now it’s your turn… Pick a photograph you want to improve. You can bring a photo from home - if it’s not already in digital format you can use the SmartLab scanner. Or take a picture of something in the SmartLab - like your partner! Decide how it can be improved and use Photoshop to make it better. Be sure to keep your original and save your work as a new file! Try making different sizes for print and computer viewing.
What do all those tools in the toolbar do? Pick six different tools and find out how they work. Remember that if you right-click a tool icon you’ll find other related tool choices underneath. Be sure to experiment with the settings in the tool options bar too! Learn how selections work in Photoshop. Browse the help menu for tips and try out the lasso, marquee and magic wand tools. Experiment with Photoshop filters. Open the “Filter” pull-down menu and see what happens when you apply different filters to your photo. Do a web search on “Photoshop tutorial”. Pick a project or technique that looks interesting and try it out. Write a short tutorial for a tool or technique in Photoshop that will help your classmates in their projects! Do a web search for “Vector vs. Bitmap Graphics” to learn more and gain valuable insights from professional graphic designers. Extend Yourself…