Digital Entertainment Digital Photography
© 2003 by TiVo Inc. Reproduction in whole or in part without written permission is prohibited. All rights reserved. Printed in the USA. TiVo, TiVo Central, and TiVolution are registered trademarks of TiVo Inc. The TiVo logo; TiVo, TV Your Way, Home Media Option, Season Pass; and WishList are trademarks of TiVo Inc., 2160 Gold Street, P.O. Box 2160, Alviso, CA 95002-2160. All other trademarks are the properties of their respective owners.
3
Digital Photography 21
Introduction
21
What is Digital Photography?
22
Benefits of Digital Photography
24
Getting Started with Digital Photography
29
Digital Photography and TiVo
27
Taking Great Pictures
29
Where to Find More Information
3
Digital Photography
20
3 Introduction High-quality digital cameras are finally affordable. This document explains some of the benefits of digital photography, and gives you some information to get you started. After reading this document, you will know the basics of digital photography, including: • resolution • compression • image processing • how to take great pictures If you know how to use a computer, but you are not an expert on digital photography, read on!
What is Digital Photography? Instead of recording images on film, digital cameras use an electronic method to capture an image, then store it in computer memory. Usually, the image is recorded using a sensor called a charge-coupled device (CCD), then stored on a memory chip. One difference between digital photography and film is that in digital photography it is the camera itself that determines the image quality. With a traditional camera, different films produce different kinds of images from the same camera; with a digital camera, the “film” is really the CCD that is built in. The CCD governs the maximum resolution of the images from the digital camera. When you take a picture, software within the camera stores the file in memory, sometimes compressing the image to save space. The following paragraphs give a little more information about resolution and compression. Resolution. Just as certain films are grainier and others are sharper, different digital cameras record images in different ways. Digital cameras are rated on the basis of their maximum resolution. Resolution is the characteristic of an image that allows it to show more detail. In film photography, this is related to the size of the grain; smaller grain provides higher resolution. In digital photographs, the number of picture elements (pixels) in a photograph determines its resolution. Pixels are the dots that make up the picture. Many small pixels result in a more detailed image than fewer, larger pixels. Most digital cameras have a resolution of over one megapixel (one million pixels). This resolution is sufficient for normal-sized snapshots. Higherresolution cameras (4 megapixels and higher) can take pictures suitable for 8 x 10 or larger prints.
3
Digital Photography
Compression. Digital photographs can result in very large files. A twomegapixel image containing 24 bits of color information per pixel would occupy about 6 megabytes of space on disk, if no compression were used. Different image file types use different kinds of compression. A few common image file formats are: • Compuserve GIF (Graphical Image Format) • JPEG (Joint Photographic Experts Group) • TIFF (Tagged Image File Format) Most digital cameras store images as either TIFF or JPEG files. TIFF files do not compress files as drastically as JPEG files, so you can generally fit fewer TIFF files than JPEG files on the same memory card. JPEG files use “lossy” compression, however, meaning that the image quality suffers as the file size is reduced; the compression used in TIFF is lossless.
Benefits of Digital Photography Digital photography, which was once clearly inferior to film, has matured into a technology that promises to revolutionize the way people think of snapshots. Connected to your personal computer, a digital camera makes it easy to: • avoid the cost of film and developing • print only the photos you like • take photos in low light • organize your photos without shoeboxes • e-mail your photos to friends • view a slide show of your photos • order prints of your photos online • create a CD of your photos • delete photos you don’t want • put your photos on the Web • add special effects to your photos • remove red-eye The following paragraphs give a little more information about each of the above benefits. Avoid the cost of film and developing. Digital cameras may be a little pricier than their film counterparts, but saving on film and developing makes up for it in the long run. With a film camera, you have to pay for developing all 22
3 the photographs before you can even see which ones you like. Using a digital camera avoids the expense and delay of film processing. Print only the photos you like. A digital camera lets you see your pictures before you print them. That way, you don’t have to print the ones you don’t like. In fact, if your camera has a display screen, you can delete a bad picture right after you take it—and try again. Take photos in low light. Most digital cameras are far more sensitive than photographic film. That means you can take shots in very dim light, often without using a flash. Organize your photos without shoeboxes. Most computers now come with software for organizing a library of digital photographs. You can store your images in folders by date or subject. When you are looking for a particular photo, you can see small “thumbnail” images of all the pictures in a folder. This makes it easy to find the one you want. E-mail your photos to friends. Sharing a photo with a friend is easier than ever. Once you have your photos on the computer, you can send them to anyone you like simply by attaching them to an e-mail message. View a slide show of your photos. Some digital cameras include software that lets you view a slide show of your photos on your computer, or even on your TV using a special cable. Even better, your TiVo Series2 DVR with Home Media Option lets you use your TV to view a slide show of photos stored on your computer. Simply connect your DVR to your personal computer via a home network, and you can “publish” your photos to your DVR. Then you can show your favorite photos to your friends and family from the comfort of your couch. Order prints of your photos online. Several online services make traditional photo prints from digital photos. If you don’t have a printer at home, then these services are handy for ordering enlargements in any size. Best of all, digital means only getting prints of the photos you like. Create a CD of your photos. If your personal computer has a CD-RW drive, then burning a CD of digital photos is a snap. It’s a great way to send a large collection of photos to a friend. Put your photos on the web. Once your photos are in the computer, you can share them with friends and family by putting them on a web page. Your Internet service provider probably offers some space for a personal web site. If not, a number of online services offer web space for free. Some of them have special areas just for digital photos. Add special effects to your photos. Most digital cameras let you take pictures in black and white, change the tint, or add special effects to your photos. The image editing software that comes with most cameras usually lets you add more effects.
3
Digital Photography
Remove red-eye. The area in the center of the eye, called the pupil, normally appears dark. When you photograph someone using a flash, the pupil sometimes appears red in the picture. This happens when the flash illuminates the subject’s retina, making it visible on film. Some image editing software can automatically remove the redness, making the subject’s eyes appear normal again.
Getting Started with Digital Photography Getting started with digital photography requires some new equipment. You may already have a computer with a printer and a CD-RW drive (a CD writer). An Internet connection is useful if you want to share your digital photos on the web or via e-mail, or if you want to order prints. With a home network, you can use your TiVo Series2 DVR and Home Media Option to view a slide show of your own digital photos right on your television. To gain the full benefits of digital photography, you will find the following items useful: • digital camera • computer • image editing software • printer • memory card reader • CD writer • Internet connection • home network • TiVo Series2 DVR with Home Media Option The following sections provide information about what to look for when you are choosing equipment for digital photography.
Choosing a Digital Camera A number of factors can influence how much use and enjoyment you get out of your digital camera. The following sections provide a little information about what to look for in a digital camera.
Image Quality The most obvious measurement of image quality is resolution. You might think that the best way to buy a digital camera is to look for the most megapixels for the price. Remember that resolution and sharpness are not the same. It is important to consider other aspects of image quality, such as
24
3 compression and color fidelity. If you compare images from two different cameras, you will see differences even if the resolution is the same.
Features Most digital cameras offer effects like black and white, and several different image resolutions. However, cameras vary widely in the other features they provide. Consider the following questions when choosing a camera: Is it expandable? Does it use removable memory cards, or are you limited to the built-in memory? How many pictures can you take at the maximum resolution before the memory is full? Memory cards offer an additional advantage: if you have more than one, you may be able to download photos to your computer from one memory card while taking more pictures with another. Does it zoom? Is the zoom digital or optical, or a combination of both? Optical zoom means that the lenses control the image magnification, just as in a traditional film camera. In digital zoom, the pixels themselves are enlarged. Some cameras use optical zoom up to a certain point, then digital zoom to add a bit more magnification. Because digital zoom works by enlarging the pixels themselves, it can result in lower image clarity. Look for a camera with optical zoom. Can you view pictures on the camera? Does it have a display screen? Does it connect to your television directly? Viewing your pictures on the camera lets you weed out the shots you don’t like. That way, you preserve more free memory space for the shots you want to keep. Does it respond quickly? How long does the camera take to record an image after you press the button? How long before the camera is ready to take another picture? A camera with a long delay can make it difficult to capture the exact image you need. If your digital camera takes a half-second to respond to the shutter button, you may miss the moment when the birthday candles get blown out. If the camera requires a few seconds between shots, it limits your freedom to shoot all you want and weed out the bad pictures later. Is it easy to use? Are the controls clear and positioned sensibly? Is it compact and lightweight? Digital cameras are getting smaller, and their designs are simpler and easier to use. Before you buy a digital camera, hold it in your hands. Does it feel right? Is it obvious how to turn it on and use it? If not, then you may have trouble figuring it out when it counts. How fast does it use batteries? Can it use rechargeable batteries? Can you turn off the display screen to maximize battery life?
3
Digital Photography
Digital cameras tend to use batteries faster than film cameras. This can be expensive unless you get an efficient digital camera. Some cameras can use rechargeable batteries, which are a great way to reduce the cost. You can also usually turn off the camera’s display screen to extend the life of the batteries.
Compatibility Nowadays, almost every digital camera works with both Macintosh and Windows computers. It is especially prudent to select a digital camera that uses removable memory cards. A memory card reader is very inexpensive; if you change to an operating system that your camera does not support, you can simply buy a new memory card reader to solve the problem. When choosing a digital camera that comes with image editing software, make sure the software is compatible with your computer.
Choosing a Computer, Printer, and Software The computer, printer, and software you use to process your digital photos are almost as important as the camera itself. Although it is the camera that determines the quality of the initial image, the final picture you see depends on your other equipment.
The Computer The computer’s role is to store images, and to run the software that lets you organize and edit them. Most computers have plenty of hard disk space for storing images, and enough memory to run popular image software. These days, a new computer usually comes with a CD writer. If you don’t have one, you can buy a CD writer separately. This allows you to share large collections of high resolution photos with friends and family.
The Printer The printer is perhaps the most important piece of equipment other than the camera. It is the printer that puts your digital photos on paper; the quality of the printer can make or break a good digital image. Just as with digital cameras, resolution is a concern. Rather than being expressed in megapixels, a printer’s resolution is referred to by the number of pixels per inch. Most printers are capable of at least 1200 pixels per inch (ppi). More important than resolution, however, is the size of the ink spots that are applied to the paper. If the spot size is much larger than the pixel size, then you will not see the full benefit of the printer’s resolution. Look for a printer with a spot size of 3 to 5 picoliters for best quality. Remember that spot size varies according to the type of paper you use.
26
3 Like digital cameras, different printers deal with color in different ways. Look at sample output from several different printers before choosing one. You may find that you like a particular printer over other printers with higher resolution.
The Software Image editing software helps you organize and edit your photographs, optimize them for e-mail, fix red-eye, and add titles or special effects. If your camera does not include image editing software, you might wish to purchase a program for organizing and editing your photos. It can be really helpful to have image editing software that also includes tools for organizing your photos. Look for software that lets you put your photos into “albums” and browse through small “thumbnails” so that you can find them easily later. If you plan to e-mail photos to your friends and family, then you should reduce them to a low resolution so that the files are smaller. Otherwise, you may surprise the recipients with files that are very large. Good image editing software includes the capability to re-size your photos so that they are easy to e-mail or put on the web.
A Home Network and High-Speed Internet Connection A home network and a high-speed Internet connection can be useful if you do a lot of digital photography. Uploading a lot of photos to the web becomes a snap if you have a high-speed Internet connection. Because digital photo resolution is directly related to file size, you may find yourself dealing with many large files. If you want to transfer them between computers in the home, a home network will make the process much faster and easier. In addition, your TiVo Series2 DVR with Home Media Option can display photos from your PC using the network. For more information about home networking, see Chapter 4, “Networking Made Easy.”
Taking Great Pictures If you have your digital camera, computer, and printer, then you’re ready to get started taking great pictures! Here’s some information about how to get the most out of digital photography.
Composing Your Photograph Most of what you know about taking pictures is true about digital photography as well. For example:
3
Digital Photography
• almost any scene looks better if you get closer • holding the camera steady is crucial to a sharp photograph • cloudy days are better than sunny days for photographing people There are some things you don’t have to worry about as much when using a digital camera. For example, digital cameras deal with extremes of contrast better than film. This makes it easier to get good pictures even on sunny days or in dimly-lit interiors. Digital cameras are more sensitive to light than most film, so you may find that you can take pictures in extremely low light. In dimly-lit scenes, the camera requires a longer exposure than normal, and you must make sure the camera does not move until the exposure is finished. If you plan to do a lot of night photography, a tripod is a good investment. Here are a few pointers about taking pictures with a digital camera. Know when to shoot. You may have to deal with a slight delay between pressing the button and capturing the image on a digital camera. Keep this in mind when you are composing a photograph. You might want to press the button before your subjects say “cheese,” if the camera has a significant delay. Make sure your resolution is set properly. If you need to take a lot of photographs at one time, or if you do not want to make prints from your photographs, then you can use a low resolution. However, if you believe you might print your photos later, you should you the maximum resolution for the best quality. Set your white balance. Different kinds of light have different colors. If you’ve ever looked into an office building at night, you may have noticed that the fluorescent lighting is actually greenish. Your eyes naturally correct the color so that the light doesn’t look green if you are in a room with fluorescent lights. A white piece of paper in an office looks white, not green. Your digital camera does its best to correct the color of the photographs in the same way. This correction is called white balance, an adjustment to the color so that the dominant light looks white. Most cameras do a good job adjusting their white balance automatically, but in some cases you may decide to re-adjust the white balance manually. Use the display screen. Most digital cameras have a viewfinder, so that you don’t use up your batteries by using your display screen all the time. However, if you need to compose a photograph exactly, then using the display screen is handy because it gives you an accurate picture of exactly what is in frame. This is especially useful in close-up shots, because the viewfinder is less accurate closer to the subject. Know when to zoom. Read your camera’s instructions carefully so that you know how much you can zoom optically. If you venture past the optical
28
3 zoom limits of the camera, you are on digital zoom territory. Digital zooming may adversely affect the quality of your image. Know what you can fix later. Some problems can be fixed after you transfer the pictures to your computer. If an image is slightly dark or has an unpleasant color tint, you might be able to adjust the brightness and color settings later. However, if an image is blurred or the resolution is set too low, you are better off taking the picture again. Weed out what you don’t want. The greatest advantage of the digital camera is that you don’t have to keep the shots you don’t want. Take the time to weed out bad shots while you’re shooting. That way, you have more space left in the camera’s memory to take new photos.
Digital Photography and TiVo Digital technology has made it easy and convenient to store hundreds of snapshots in your personal computer. To find a photograph, you no longer need to haul boxes down from the attic and unwrap envelope after envelope looking for the image you want. TiVo extends the benefit of digital photography by letting you view digital photographs from the comfort of your living room. After you have used the computer to organize and edit your collection of photographs, you can sit on the couch and control a slide show on your TiVo DVR. Your pictures stay on your computer, so they don’t use any of the DVR’s recording space. The best part is that it keeps the computer out of the living room.
Where to Find More Information The following web sites provide information that will help you get started with digital photography. http://www.dcresource.com/ Reviews of the latest digital cameras, a buyer’s guide, message boards, and frequently asked questions about digital photography. http://www.dpreview.com/ Reviews and previews of digital cameras, and digital camera news. http://www.howstuffworks.com/digital-camera.htm A thorough explanation of how digital cameras work. http://electronics.cnet.com/ Comparisons and reviews of the latest electronic gadgets, including digital cameras.
3
Digital Photography
http://www.imaging-resource.com/ A wealth of information about imaging products, including digital cameras, scanners, and printers. http://www.shortcourses.com/ Education for the digital photographer, including short online courses in lighting, digital photography, and choosing a camera.
30
