Page #10 (Chapter 1. Start Here)


The Nature of Digital Photography

If you use a digital camera, you are more likely to print your photos at home rather than have a photo shop print them. Your computer essentially becomes the "film lab," making you responsible for the touch-ups and corrections you'd otherwise trust to a lab technician. Don't let this new responsibility overwhelm you. As you'll learn in this book, the Editor provides many simple-to-use tools for fixing just about any problem caused by a digital camera, scanner, or simple human error. In addition, with the Editor, you'll be able to create special effects your neighborhood film lab couldn't create.

With the Editor, you become your own photo lab technician.

With digital photography and Photoshop Elements, you become the photo processor, so you'll have to learn these principles of the digital trade:

  • Film can record more detail than digital media. It's simply the nature of the beast. To compensate, always take photos at your digital camera's highest resolution. Yes, this means you won't be able to store as many photos on the camera's memory card, but the photos you do save will be worth printing.

  • Digital photos require digital storage media. Early on in your digital photography career, you should develop a plan for managing your images. The simplest method is to copy photos from your camera to the hard disk and then back them up immediately onto a CD-R, DVD-R, or other high-volume, permanent storage medium. Next, print thumbnails of each image, select the best ones to keep, and delete the rest of the image files to reclaim storage space. You'll find that the Organizer is uniquely designed to help you with all stages in this process.

  • After making changes to your images, save copies of them. Save your images in a universal format that's recognized by other applicationsperhaps the same format your digital camera used to begin withso that they're easier to share. Compressed TIFF and JPEG are the two most common universal formats for digital photographs. Using the Organizer, back up these edited images onto a separate CD-R or other storage medium.

    TIPS

    If you're given a choice of formats to use with your digital camera, choose RAW or TIFF format over JPEG, because RAW and TIFF record and save more photographic detail than JPEG. Save these original digital images onto CD or DVD as your "digital negatives," and make copies to work on, preferably in PSD format. See the upcoming section that discusses PSD format in more detail.

    You'll find yourself overrun with digital images not long after you've purchased your digital camera. One tool for keeping them all organized and easy to locate is the Organizer portion of Photoshop Elements. See the upcoming section, Use Photoshop Elements to Organize Photos, for more information.


  • Printing good-quality photos requires a printer designed and tested not only for color, but for use with photo paper. Not all color printers are photo printers, capable of dealing with thicker, photo-quality paper. In addition, photo printers typically use six or seven tones of ink, including black, as opposed to the standard four inks you find with common color printers. So, a photo printer is well worth the extra money when you want prints that are worth archiving in albums and scrapbooks, not just thumb-tacking to your wall. If less than half of your everyday printing tasks are devoted to photos, and you want to save money, you can find a four-tone printer model that does print nice photos, if you use photographic paper specifically designed for that particular model or its brand. When comparing printer prices, compare not only the photo quality but also the price of the exclusive inks they use because that's where your greatest expense will be.

    As an alternative to buying your own color photo printer, consider those do-it-yourself printing kiosks that let you insert a CD-R or PhotoCD and print photos on high-quality photo paper. Find a kiosk in your neighborhood (many discount department stores and drug stores have one) and study the instructions so that you'll save your photos in a compatible format on a compatible medium. For occasional photo printing needs, online services such as Adobe Photoshop Services (provided by Ofoto, a Kodak company) enable you to upload your photos over the Internet, have them printed on quality stock, and delivered to you for reasonable fees.

    NOTE

    For optimum results, use only the photo paper that's compatible with your particular printer. Another consideration when printing photos at home is longevity. Archival inks and papers, although expensive, produce the best results.


  • If you intend to use the Editor to repair images scanned from old prints, invest in a good quality scanner with high resolution. Some premium scanner models include special features such as a film reader for scanning film strips and/or slides.

What You Should Know About Resolution

A digital image is comprised of a series of small dots of color and brightness called pixels. Digital TV images and the images on your computer monitor are also comprised of pixels. The higher a digital photo's resolution, the more pixels it has per inch, and thus the more detail and clarity the image can contain.

KEY TERM

Resolution In digital images, the number of pixels per inch/centimeter. The more pixels (dots) of color, the more detail an image holds. To compute resolution, multiply the number of pixels in width by the number of pixels in height for an image.

DPI (dots per inch) Because a printer uses dots of ink to produce an image, DPI is used to describe printer output. The higher the DPI, the more pixels are used to print an image, and the more detail you get in your printed image.

PPI (pixels per inch) A monitor uses pixels to display an image, so PPI (pixels per inch) is used to describe the quality of onscreen images. The higher the PPI, the larger the image file and the higher its resolution.


When editing digital images, you must always consider that the resolution you are using directly affects the quality of the final result. Onscreen, images are rendered at somewhere between 72 and 106 pixels per inch (PPI), which is quite a bit less than the 4,800 dots per inch (DPI) of most ink jet photo printers sold today. (Dye sublimation printers use a different printing technology and need only an average of 300 DPI to produce high-quality photo prints.) Because an onscreen pixel is larger than a printed dot, an onscreen image needs fewer pixels to produce the highest quality result. In other words, an onscreen image doesn't need very high resolution for you to think it looks good. So, if you are editing an image for use on the Web, in a PowerPoint presentation, or as a Windows desktop background image, a low-resolution photograph (larger pixels and fewer of them) will do just fine.

But because a printer reproduces photos by printing a greater number of dots per inch, to produce a high-quality, detailed, printout, you'll need to start with an image that has a lot of pixels (a high resolution). In other words, an image with low resolution that looks great onscreen will not look very good when printed.

Adding Text and Objects

If you view a digital photo at high magnification, it's easy to see that the image is comprised of many pixels arranged in perfect, horizontal rows. A row of pixels is called a raster. On your computer monitor, at 800x600 resolution, the display is comprised of 600 rasters. To display a black circle onscreen using raster technology, the Editor simply arranges a series of black dots in a circle pattern, and fills in the remaining spaces in each raster row with dots of the background color. The process of rendering raster objects onscreen is similar to using a Lite-Brite toy to draw a picture using rows and rows of small lights.

NOTE

The size of an onscreen image will vary depending on the screen resolution of the monitor it is being viewed on. In other words, if you're viewing an image with your monitor resolution set at 1280 by 1024, that same image will appear bigger (but with the same quality or level of detail) on a monitor set to a resolution of only 1024 by 768.


A vector is a mathematical formula that describes a line or a curve. A vector shape (such as a flower or a house) is comprised of one or more vectors; a circle or rectangle is made up of just one. A vector circle, for example, is computed by the Editor geometrically, as a series of dots set the same distance from a chosen point.

Rasters and vectors are not important in image editing until you decide to add text or drawn objects to a photo. It's at that point you'll need to choose between raster data and vector data.

KEY TERM

Raster data Data comprised of individual pixels, each with its own hue, saturation, and brightness value.

Vector data Data stored as a series of mathematical formulas that plot the coordinates of points along the edges of a shape, such as a star or a bit of vector text.

Anti-aliasing The addition of semi-transparent pixels along the curved edge of a shape or selection. Anti-aliasing helps curves look smooth and not jagged.


In the Editor, geometric elements such as shapes, curves, lines, and text are rendered on a vector layer. Image content (such as a digital photograph or a scanned image) and objects you paint with the Brush tool or draw with the Pencil tool on a layer are rendered on a raster layer. On the vector layer, the boundaries of objects and text are plotted mathematically and filled in with color. Normally, the edges of vector objects are smooth and clean because they are rendered mathematically. But because the Editor renders the contents of its vector layer on a grid with the same resolution as all the other raster layers in an image, curved or diagonal content might appear jagged or stair-stepped when viewed at a high magnification. This fact makes that same data look jagged when printed.

Not to worry though; the Editor automatically compensates for the "jaggies" through a process called anti-aliasing. Anti-aliasing smoothes curves by adding semi-transparent pixels that "fuzz" the edges and fool the eye. Your eye, as it turns out, will more readily forgive the watery borders caused by anti-aliasing than it will ignore the stair-step look of a non-anti-aliased curve. When creating text, you can turn on anti-aliasing to smooth curved letters and numbers.

NOTE

Jagged curves also becomes a factor when you are copying or moving selected data from one place to another: You can use a technique called feathering to blur the edge of the selection and blend the selected data into its new surroundings more easily.


Anti-aliasing of this text blends otherwise jagged edges with their background by adding shades of the object color along its edges.

NOTES

Photoshop Elements retains vector data as such until you save your image in a format that does not support separate layers, such as BMP, JPG, GIF, or TIFF (with the Layers turned off when saving the image). At that point, vector data is converted to raster data and merged with data on other layers to produce a single, flat, raster layer.

To save vector data so that you can edit it when needed, use the Photoshop format as described later in this chapter, or save the image in TIFF format with the Layers option in the Save As dialog box enabled. Using TIFF to save your layer data might make the image file unreadable by non-Adobe programs.


So, why does the Editor use vector technology on drawn objects and text, and then typically reduce images to raster data? One advantage in using vector data is that it can be easily changed. After drawing a vector object, you can reselect it with one click and change its size, position, color, and so on. And the edges of the vector object will be just as smooth even if you enlarge the object by a great deal. Because text is created using vector data, you can also easily edit it without damaging the image beneath it. On the other hand, raster data (which you create with the painting tools) is really only a series of dots. So, the only way to "edit" a diagonal line comprised solely of pixels painted onto an image is to systematically repaint each dot.

About Color Models and Optics

Digital images (such as photographs) are comprised of a series of pixels; each pixel has various characteristics that describe its color. For example, a pixel might be pale yellow-green. How the computer decides to make that pixel pale yellow-green depends on a specific color model. The Editor uses two color models interchangeably: RGB and HSB. This means that for any given pixel, there are two different ways to describe its color: as a mixture of the optical primaries red, green, and blue (RGB); or as given hue with a specific saturation and brightness (HSB).

Color models become important whenever you're asked to make a color choice in the Editor. For example, if you want to add some text or paint with one of the painting tools, you must choose the color you want to apply. You can use the RGB color model or the HSB color model by using the Color Picker to do just thatneither color model is necessarily better than the other; you simply use the one you prefer.

The Color Picker represents pixel colors using two models simultaneously.

NOTE

When you look at colors displayed in the Color Picker, you'll discover the absence of certain colors you would swear were realkhaki colors, "earth tones," sandy shades. They're blends that can't be described by an optical color modelone based on light. A digital photograph (whether captured by a digital camera or scanned in using a scanner) simulates these natural colors by placing two or more pixels with often wildly different hues next to each other and letting the mind create the color by blending the pixels.


In the RGB model, the three optical primaries red, green, and blue are expressed in terms of their relative intensities, from 0 to 255. As you choose a color from the Color Picker, the relative amount of red, green, and blue contained in that color is displayed in the corresponding R, G, and B boxes. The purest, brightest red would be defined as an RGB value { 255, 0, 0} or red with no green or blue. Cyan is created by mixing equal parts of green and blue with no red { 0, 255, 255} . Medium gray is produced by mixing red, green, and blue equally, at roughly half strength { 129, 129, 129} . White is produced by mixing the three colors evenly at full strength { 255, 255, 255} . Black is produced on your monitor by adding no light at all { 0, 0, 0}.

The second color model, named for the three attributes hue, saturation, and brightness (HSB), also describes every color that Windows and your monitor can display. In the HSB model, the hue (H) value is represented by a color's location on the optical color wheel. There are 360 degrees in a circle, and thus each hue is represented by its angle or degree on this circle. The color wheel begins at red, transitioning through magenta, blue, cyan, green, and yellow, then back to red again. When the H for Hue is enabled, all possible hues are represented on the Color Picker by the color slider, located to the right of the color field.

The saturation level (S) refers to how much of that hue appears in the blended color. To "remove" the hue from the final color, the color opposite that hue on the color wheel is added. To you, adjusting the saturation of a color will look like you're adding white, because optically, when you equally blend two colors that are opposite on the color wheel, you get white. When the S option is enabled in the Color Picker, the color slider shows colors from the pure hue to white. A value of 0% S for Saturation means that none of the hue is present in the final color, so it will therefore look completely white. A value of 100% for Saturation means that the final color is completely saturated with the chosen hue, without a hint of its opposite added (such as a pure yellow).

NOTE

Okay, there's a third way to specify color in the Color Picker: by entering a specific HTML color code in the # box. The code uses six hexadecimal (base-16) digits, where the first pair stands for the red value, the second pair for green, and the third pair for blue. Whereas we commonly use digits 0 through 9 with everyday numbers (base-10), hexadecimal proceeds from 0 to 9 and up to A through F (to represent 10 through 15). So, A0 represents 160, and FF represents 255.


Brightness (B) represents the blended color's degree of light. Here, a value of 0% represents total darkness (black), and 100% is a color with no black added at all. When the B option is enabled in the Color Picker, the colors on the color slider range from the blended color to pure black. You'll learn the specifics behind selecting a color using both the RGB and HSB color models in 113 Select a Color to Work With.

Why Printing a Photograph Isn't So Easy

See Also

64 About Printing Images

105 Ensure That What You See Is What You Get


Until now, you're probably used to printing mostly cards, letters, spreadsheets, and other everyday work documents, and you've come to expect that your printed results will match your onscreen view pretty closely. When you first enter the realm of digital photography, however, there may come a moment after printing your first image when you think, "That isn't how it looked onscreen." It's then that you start to realize that no two devices ever worked so differently from one another as your monitor and your printer.

A computer monitor uses varying intensities of the three optical primary colors to create each pixeleven the white ones. These optical primaries are red, green, and blue. The science of light (optics) is an additive process. You start with the absence of light (black), and then add light to make color. Theoretically, every hue in the rainbow can be created with any combination of the three primaries. Imagine shining a red flashlight and a green flashlight at the same spot, and watching their combined output become a yellow light, and you'll get the idea.

Your color inkjet printer mixes colors following the rules of pigment, in which cyan, magenta, and yellow are the primary colors of ink or dye. A color inkjet has as few as four inks (with black being the fourth), or as many as seven different inks to work with. Rather than employing the optical process of adding light to attain the desired color, printing employs what's called a subtractive process. This theory works in precisely the opposite direction of optics. The subtractive process presumes that the purest light an object can reflect is white, so an object's color can be simulated by applying colored pigment or dye to mask out, or subtract, just those hues that an object absorbs and does not reflect. During printing, magenta is applied to the color of an object because the object appears to reflect red and blue light (megenta's two optical components) and absorbor not reflectgreen light.

NOTE

Because your monitor mixes light to make colors, in its system, red and green make yellow, green and blue make cyan, and red and blue make magenta. This might be a foreign concept for you, especially because it's so different from what you may have done as a child, when mixing yellow and blue made blue, red and blue made purple, and so on. A color printer uses a color mixing system known as CMYK, where the three primary colors are cyan (the closest thing to blue in a transparent ink), magenta (a kind of red), and yellow.


Theoretically, if your inkjet printer were to mix equal amounts of cyan, magenta, and yellow ink in a given area, the inks would cancel out all reflected light, and the product would be black. In practice, however, because inks tend to introduce certain impurities, the product is actually a muddy brown. So, printers add a fourth pass, with black ink, to make darker portions bolder. Thus the name commonly given to the four-pigment process, CMYK (where the "K" stands for black). Recall from our earlier discussion of optics that cyan, magenta, and yellow just happen to be the three secondary hues in optics. This is the critical connection between optics and pigment, and this is why cyan, magenta, and yellow are the three basic inks used in process printing. Still, because the monitor and the printer use two different color models to create color, it's up to your program (in this case, Photoshop Elements) to do the best job it can in translating between the two. Photoshop Elements uses certain files called ICC color profiles to help it do just that. ICC color profiles help translate color information from your monitor's RGB color model to your printer's CMYK color model.

NOTE

You'll learn more about color profiles and how to install them in 105 Ensure That What You See Is What You Get.


Windows typically installs a color profile for translating optical shades to printed shades so that what you see onscreen looks the same when printed. When you installed your printer, the software it uses might have overridden this default color profile with one that's better suited to your printer. But it might not have done so. In any case, this book will show you not only how to install the best color profiles for your system, but also how to make subtle color corrections to your images onscreen so that you'll get the best printed result.

TIPS

Do not put batteries in your pocket unless they are enclosed in a plastic case; if the batteries come in contact with metal (keys, change, and the like) they will discharge and burn you.

If you use a card reader to transfer images to the computer, don't ask your computer to format a memory card for you because it might cause errors. Instead, format your memory card in the camera by selecting that option off the camera's menu.


How to Take Better Photographs

Even with the help of a good graphics editor such as the Photoshop Elements Editor, learning a few things about what makes a more optically appealing photograph will save you time editing your images later on. Here are some simple things you should know:

  • Be prepared. You can't take a picture if your camera's batteries are low or if you're out of memory. Invest in some extra batteries and plenty of memory cards or sticks and always keep them handy and ready to use. With ample backup power and storage media on hand, you'll be more relaxed, so when you take a shot you know isn't perfect, you can easily try again.

  • Don't skimp on quality. Unless you're capturing an image for email or Web use only, always shoot at the highest resolution your camera allows. If you decide after the fact that a particular photo will make a nice 8"x10" print, you won't be able to get a quality result if you skimped on the resolution when taking the picture. In addition, if image compression is a variable on your camera, select low or even none.

    NOTES

    Low-resolution digital images are always much grainier than their higher-resolution cousinsa problem you cannot really fix, even with the help of a graphics editor. So, don't skimp on image resolution when taking photographsyou will always regret it.

    Photoshop Elements supports some digital cameras' RAW formats. If yours is supported, you can save your images using the camera's RAW format, which basically preserves all the image information without loss, as a kind of "digital negative." A list of supported cameras appears on Adobe's Web site at http://www.adobe.com/products/photoshop/cameraraw.html.


  • Take lots of pictures. The reason professional photographers can get that one really great shot is because they take far more than just one. This is especially true of candid moments, group photos, subjects in motion, or with less-than-perfect lighting conditions. Taking more than one photo also enables you to easily experiment with exposure and shutter speed settings, and maybe even a different lens (such as a wide-angle, telephoto, or fisheye lens). Later, you can choose the best image and discard the rest.

  • Study the light. Locate the brightest and darkest areas of the scene you're capturing and determine how one affects the other. Is the sun shining right in your subject's face, causing her to squint and frown? Does the sunlight falling from behind put her face in shadow? Is your subject much brighter or darker than the background? If so, you might want to change your position, or adjust the exposure value (plus or minus) to compensate for low light/bright light conditions. For example, you might be trying to take a nice picture of your child playing in the snow, but the camera sets the exposure automatically for the brightest object (the snow); as a result, your child's face is underexposed. The same situation happens when the sun is behind your subject and his face is in shadow, or the sun is in the picture when you're trying to capture the sunset. To compensate for over-bright elements in a scene, set the exposure value to plus 1 or 2 and reshoot. To compensate for deep shadows, dark foliage, or a dark subject against a light background, adjust the exposure value to minus 1 or 2.

  • Get white right. Whenever the lighting conditions change, white balance your camera. Typically, white balancing involves making a lighting choice from a menu or the mode button (such as indoors, outdoors, snow, cloudy day, nighttime, stage lighting, and so on). More sophisticated digital camera models enable you to select the white balance option, point it toward something white or near white, and white balance automatically, so that the temperature and quality of the light you capture is adjusted for the light in the scene you're shooting. Unless you white balance the camera to match the current lighting conditions, flesh tones can look too blue or too orange.

    KEY TERM

    White balance To adjust the color balance of the camera to the current lighting conditions so that the colors in the resulting photo are "true."


    NOTE

    White balancing allows the camera to compensate for color shifts caused by the source of light. For example, under a florescent light, things can look a bit blue because the light source is cool; outdoors, things tend toward orange because the light source is warmer. If conditions change after you white balance the camera (you move indoors or it starts to cloud up for example) be sure to white balance the camera again.


  • Don't "auto" everything. Get involved in the picture-taking process. Use the flash to provide fill light even in the daytime, softening shadows on a subject's face. Some cameras enable you to adjust the flash output so that the flash won't overwhelm a subject and drain its color.

    Control light by manually selecting the f-stop (aperture). A large aperture such as F2 helps you capture images under low-light conditions; a smaller aperture such as F16 is more appropriate for daylight conditions. When needed, you might choose to manually set the shutter speed instead.

  • Throw the background out of focus. A great way to bring out your subject (and improve a photo's composition) is to blur the background behind it. This is easily accomplished by manually selecting a large aperture (such as F2 or F4) to create a small depth of field. To capture a subject and the detail in the background around it, create a large depth of field by selecting a small aperture such as F12 or F16.

    KEY TERMS

    Depth of field The distance between the closest and farthest in-focus objects.


    By blurring the background, this little girl, and not the festival crowd, becomes the most important element in this photograph.

    NOTE

    Two other factors affect depth of field: zoom and camera-to-subject distance. As you zoom in on a subject, the depth of field gets smaller. To increase the depth of field, zoom out. In addition, as you move closer to a subject and refocus, the depth of field becomes more shallow. To increase the depth of field, move back from your subject and refocus.


  • Get rid of the shakes. Whenever you can, use a tripod. For most digital cameras, there's an interminable wait between the time you press the shutter release and the time the camera records the image. Holding a camera perfectly still during this waiting period can be almost impossible. Invest in a small pocket tripod to steady your camera and remove unnecessary blur, especially when you've zoomed in on a far-away subject or are shooting in low-light conditions. Alternatively, use your surroundings as a surrogate tripod.

    TIP

    The world is your tripod if you only looka park bench, car roof, tree branch, stone railing, or countertop all make perfectly legitimate tripod substitutes. If you can't find a reasonable "tripod," bring your elbows in, take a breath, and release it slowly as you gently press the shutter. Never stab at the shutter because doing so can move the camera.


  • Be careful of zoom. Most digital cameras offer a digital zoom, where the camera artificially increases its maximum optical zoom factor by essentially cropping a region from the optical image and magnifying that same region. Digitally zoomed images are grainy, even blocky, as a result. If you want a quality photograph, don't zoom in past the natural optical zoom level of your digital camera's lens. Some digital cameras even give you the option of turning off the digital zoom so that you can't accidentally engage it.

    TIP

    If you want a great photograph of a friend or relative, become an observer. At get-togethers, blend into the background and discretely take photos only when the moment is right. Your patience will be rewarded with a candid photo that captures people as they really arebeautiful and human. This trick also works well with nature photographs of birds, butterflies, and squirrels at play. As a diver once put it, take only pictures and leave only bubbles.


  • Frame it right. Some digital cameras come with a viewfinder and a larger liquid crystal display (LCD) screen for displaying pictures. To properly frame subjects that are close to the lens, you must use the camera's LCD and not the viewfinder, because the viewfinder renders the scene a bit to one side.

  • Take better landscapes. One mistake new photographers often make when taking pictures of a far-off vista is to simply press the shutter button, making the camera focus on that far away mountaintop. The result is a blurring of most of the foreground. To keep more of the foreground in focus, focus on something about 1/3 of the distance from you to that mountaintop and then press the shutter button partway. Then, while still holding the shutter button partway down, reframe the picture and press the button the rest of the way to take the photograph.



Adobe Photoshop Elements 3 in a Snap
Adobe Photoshop Elements 3 in a Snap
ISBN: 067232668X
EAN: 2147483647
Year: 2006
Pages: 263

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