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Digital imaging is big and getting bigger everyday. It's become very popular with point-and-shooters and "non-photographers" who just want to record family moments, and with pro photojournalists. It's also big with studio product photographers, although their computer-tethered devices are beyond the scope of this guide. But digital is also making inroads with photo enthusiasts and "serious" amateur photographers. Today, there are lots of choices, whatever your digicam needs. Digicams offer several advantages over film cameras. For starters, you don't have to buy film—or pay for processing. And you get instant gratification—you can see your image right after you shoot it. If you don't like the image, you can correct the problem and reshoot it better on the spot—or just erase it and try something else. And digicams automatically digitize your photos as you shoot, so they're ready to use in your computer. And it's easier to keep track of your digital images than it is to keep track of a bunch of film negatives and prints—there are several software programs designed specifically to make it really easy to find specific shots. And you can archive a bunch of images on an easy-to-store $1 CD. Of course, digital cameras have their downside, too. None of the "affordable" ones can match 35mm film in image quality. Because many require that you scroll through menus on the LCD monitor to make camera settings, they're often more difficult to learn and use than film cameras. Digicams that provide the same range of versatility as an entry-level AF 35mm SLR cost several times as much. And while you don't have to buy film, you have to buy memory cards to hold your images as you shoot (and those aren't cheap, although they are reusable), and some form of storage for your "keepers" after you shoot (CD and DVD burners are the hot answer to this today). Before we get into specific camera models, let's look at some information you ought to know before you buy a digital camera. Pixels
Ever since the first "megapixel" digicam was introduced, the hottest buzzword in the digicam world is "megapixel." Digital images are composed of tiny "square dots" called picture elements, or "pixels." The more pixels an image has, the better its resolution—the more detail it will have, and the bigger you can "blow it up." A megapixel is a million pixels. A one-megapixel digital camera, at its maximum quality setting, produces images composed of approximately 1,000,000 individual "square dots" (actually, most "megapixel" cameras provide an image measuring 1152x864 pixels, which works out to 995,328 pixels, or .995 megapixel). A two-megapixel camera produces images composed of approximately two million picture elements (again, commonly a little less: 1600x1200, or 1.92 megapixels). A three-megapixel camera produces images composed of around three million pixels (actually, most give you a bonus: 2048x1536 pixels, or 3.14 megapixels), a four-megapixel camera, images of around four million pixels (2272x1704 pixels, or 3.87 megapixels), a five-megapixel camera, images of around five megapixels (2560x1920 pixels, or 4.9 megapixels), and so on. Most digital cameras utilize some of the image sensor's pixels for non-image stuff, so compare the actual horizontal-by-vertical pixel resolutions to get an idea of two cameras' relative resolutions. What do these pixel counts mean from a practical standpoint? Well, a common rule of thumb for publishing digital images is that you need 300 dpi (dots per inch) at the printed size for top image quality. Divide the digicam's pixel image dimensions by 300, and that's how big you can run it in a magazine like this one, in inches: a 1600x1200-pixel (two-megapixel) image can thus be run up to 5.3x4 inches, a 2048x1536-pixel (three-megapixel) image up to 6.8x5.1 inches, and so on. In reality, you generally can make a good 8x10-inch print from a two-megapixel image, and a good 11x14-inch print from a three-megapixel image, and a good 11x17-inch print from a four-megapixel image on a photo-quality inkjet printer. As with 35mm film images, how big you can blow them up really depends on your personal standards—what one viewer considers fine, another might find unacceptable. It's a really good idea to view some prints made from a specific digicam's images before buying, if you intend to print your images. Just for reference, the general consensus is that it takes at least an eight-megapixel image to match 35mm film quality. Only two of today's stand-alone single-shot digicams delivers eight megapixels (the 14-megapixel Kodak DCS Pro 14n and the 11-megapixel Canon EOS-1Ds). However, there are single-shot backs for medium-format cameras that go as high as 16 megapixels (4080x4080 pixels). And the highest-resolution digital cameras are scanning backs for medium- and large-format cameras, which make exposures like a scanner, by moving the sensor across the image plane in tiny stepped increments. Of course, this rules out moving subjects, or even hand-held shooting. (Also, these high-res backs must be connected to a computer, pretty well confining them to the studio—although we know of one photographer who took a large-format scanning back and a laptop computer on the road, doing high-quality digital landscape photography.) But you do get better-than-film-quality images. Medium-format scanning backs go as high as 49 megapixels (7000x7000 pixels), and the current "pixel king" is an over-$30,000 scanning back for 4x5 cameras, which delivers 10,500x12,600 pixels—more than 130 megapixels, a 380 MB file! By the way, 640x480 pixels (0.3 megapixel) is fine for e-mailing and Website use—in fact, high-resolution files are not good for e-mailing and Web use, due to their large file size. Other Important Stuff
Of course, more factors than just pixel count contribute to image quality. The image-sensor's dynamic range and color response, and the camera's (or scanner's) lens and electronics also come into play, as does file compression—the more an image is compressed, the less space it will take up, but the lower the image quality (some digicams allow you to shoot images uncompressed when desired, and some use more efficient compression methods than others). Unfortunately, the only way to know whether a digital camera's (or scanner's) output suits your needs is to check it out for yourself, by visiting a retailer that sells the product(s) in question, or by consulting friends who have the devices. User reports in photo magazines, and this guide, will give you a starting point, but you should see the results with your own eyes before plunking down a lot of money for a digicam or scanner. Camera Features
Pixel count is the most frequently used standard for classifying digital cameras, but camera features should also be considered. For example, Nikon's under-$500 Coolpix 4300 consumer digicam produces images with a higher pixel count (3.87MP) than the company's D1h pro digital SLR (2.64MP), but the D1h is a pro-level AF SLR with higher performance, the ability to shoot up to 40 shots at 5 fps at full resolution, and the ability to use a wide range of excellent Nikkor interchangeable lenses. (Nikon also offers a D1x version, with 5.32MP resolution, and the 6-megapixel D100—more on these later.) Even among the consumer digicams, there are more things to consider than just pixel count. Do you want a zoom lens? (The optical zoom range is what's important—"digital zoom" just "crops in" on the existing image, reducing the number of pixels and thus the resolution.) Does the camera have an optical viewfinder as well as an LCD monitor? (Running the LCD monitor all the time really uses up batteries, many monitors are hard to see in daylight, and viewing via the monitor doesn't make for steady hand-holding of the camera.) Some digicams have rotating monitors—handy for odd-angle and low-leve shooting. What storage medium does the camera use? (Built-in memory fills up quickly—if the camera accepts interchangeable memory cards, you can just remove the full card, replace it with a new one, and continue shooting. fortunately, nearly all digicams produced today accept memory cards of one type or another.) What file compression does it use? (Uncompressed files produce the best image quality, and some cameras don't allow you to shoot uncompressed images. JPEG is a common, and good, method of compression.) How easy/hard is it to download images to your computer? (Most of today's consumer digicams use a USB interface—if you have an older computer that doesn't have USB, make sure you can connect your digicam to your computer. Of course, a card reader for your computer makes downloading images a snap.) How about camera size? (They run from easily pocketable to pretty big—the teeny ones are easy to carry but a bit awkward for folks with larger hands; the big ones generally have more features.) How about power sources? (As mentioned, LCD monitors use up batteries very quickly. And that can get expensive with use-once AAs. If the camera accepts rechargeable batteries, you can re-use them. And if it has an AC adapter, you can run it off AC current when downloading images, or when shooting indoors, and thus extend battery life.) What items are standard and which are extra-cost options? (If rechargeable batteries and a charger are standard equipment, that's very good. If the camera uses memory cards—and we wouldn't buy one that doesn't use cards or other removable storage—it should come with one, the bigger-capacity the better.) What software does the camera come with? (Most come with proprietary software, plus an entry-level or intermediate image-editing program, and some bonus demo software.) Of course, a huge consideration is ease of use. In general, digicams are more difficult to operate than film cameras, because many require you to scroll through menus on the LCD monitor to make settings. Once set, the digicam is simple to operate, but setting it can be a pain. This is another reason why it's wise to try before you buy. Some models are easier to use than others, and the only way you'll know whether you like the way a specific camera works is to try it.
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