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Before You Buy A Digital Camera

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Hardware April 2001 • Vol.9 Issue 4 Page(s) 5-7 in print issue	Add To My Personal Library
Before You Buy A Digital Camera Be A Smart Shopper

A digital camera can be a major purchase. If you're not 100% confident about delving into digital, perhaps you should listen to those who argue against it. Your co-workers probably won't try to dissuade you, and the camera shop salesperson definitely won't. So let's start out by testing your resolve.

Bad News First. Despite its many attributes, digital photography is still not for everyone. While the old arguments about digital not providing the same image quality as film and not being as convenient have largely disappeared, the issue of cost is still with us. If features are what matter to you, film cameras are still vastly less expensive than digital.

Digital cameras tend not to perform as well as film under low-light conditions. They have far less tolerance for stop-motion shooting scenes, such as sports. Until very recently, digital cameras have severely lagged behind film optical zoom capabilities, and even today's entry-level 6X to 10X digital models run in the $800 to $1,000 range. If you want the ability to swap lenses, as nearly every SLR film camera can do, be prepared to double those figures.

A disposable underwater film camera costs between $10 and $15. Shooting a digital camera underwater will cost hundreds. If your film camera gets submerged in fresh water, most routine service shops can have it back in normal order for a minimal charge. With digital, you're probably going to replace the camera.

Film itself has been around for more than a hundred years, and its resilience is formidable. By comparison, digital memory cards are as fragile as they are expensive, and no one ever lost a film image because the album "crashed." Artists will be concerned about the longevity of their print images. Properly cared-for daguerreotypes from the 1800s are still in fine shape while the output from your desktop photo printer is likely to severely fade in only a few years. (The exception is with archival inks, such as those from Epson, although these will come with a steep price tag.)

All of these drawbacks, however, apply to the minority of users. For those who photograph sporting events or underwater reefs, there's still the option to shoot film and digitally scan the negatives. Good formats don't fall over dead; they just fade from glory. Even glass negative processes, which haven't been popular for over a century, are still used occasionally in the astronomical field.

We're here to congratulate you if you can live with the current digital camera limitations. The quality and convenience of digital cameras continues to evolve at a lightning pace, and the time to go digital is now. Let's continue and make sure you get the best camera for your needs.

Five Things You Must Know. As with all matters technological, there are enough specifications and acronyms surrounding digital cameras to make your head spin. However, five items stand out as being paramount to your understanding and buying process. If you don't consider each of these in its turn, you will live to regret it.

You can use IBM's tiny Microdrive as a storage
medium in some cameras.

Resolution. Like the network of cones and rods at the back of your eye's retina, digital cameras use a light-sensitive array of sensors called a CCD (charge-coupled device) or CMOS (complementary metal-oxide semiconductor) to record images. Both methods capture images as collections of dots, or pixels, and the total number of rows and columns of pixels is referred to as the camera's resolution. A resolution of 2048 pixels across by 1536 pixels down yields 3,145,728 total image pixels, or 3.1 megapixels. The higher the resolution, the more detail your images will have.

As discussed in the "When Size Matters" sidebar, resolution directly affects your image's printable size. Resolution can be artificially increased through a process called interpolation in order to help boost print sizes. Interpolation creates new pixels based on the color values of adjacent pixels. For instance, if you have two black side-by-side pixels, the computer will usually assume it's safe to insert another black pixel between them, thus increasing the size of that pixel group. Unfortunately, interpolation can have mixed results. The process only magnifies existing information and does not pick up missing details, so the end product may have a blocky, pixelated look depending on how much interpolation is applied. While interpolation is generally applied in PC-based editing software, few digital cameras use built-in interpolation and report these inflated numbers in their marketing specs. Always check the optical specifications of the CCD to make sure your 4.3 megapixel camera isn't actually using a 3.1MP CCD in disguise.

Zoom. Taking good photographs often means getting up close and personal with your subject, but you can't always walk right up to your target. Zoom functionality can be expensive, but the payoff in picture quality is ample. If you opt for a low-end camera without zoom, you face a two-fold dilemma: not only will you usually be unable to make your subject fill the frame, but also because low-end cameras are often low-resolution, you'll have poorer detail in the frame area you value most.

As with interpolation, some vendors opt to simulate quality by offering digital zoom. Whereas optical zoom actually moves the lens' elements in order to magnify an image, digital zoom merely takes the pixels from the image's center and blows them up. If you have an image that is 2,000 x 1,000 pixels and you apply 2X digital zoom, the central 1,000 x 500 pixels are doubled. In other words, you're still looking at a 2,000 x 1,000 image, but in terms of actual information, all you're getting is 1,000 x 500 of the original scene. In essence, digital zoom may be a handy cropping tool, but optical zoom is the only type that can help your photography. Particularly if you do a lot of outdoor shooting, try to get the highest optical zoom specs you can afford.

Also make sure your lens and/or camera supports a macro mode if you plan on doing up-close shooting. At the very least, check to see what the minimum focal distance is for your camera, as this can vary widely between models.

Memory. Cameras are like computers: Always get the most memory possible because you will inevitably use it all. There are currently five kinds of memory being used in digital cameras. SM (SmartMedia) and CF (Compact Flash) are the oldest and most prominent. SmartMedia has the arguable advantage of being a bit smaller (and thus easier to lose or crunch) and is generally faster than CF. Lexar Media has designed a CompactFlash card that uses USB (Universal Serial Bus) technology to accelerate picture transfer times, although SM still tends to record large images more quickly. CF's true advantage is its increasingly large storage capacity. Iomega, for example, markets IBM's 340MB Microdrive, which is an actual hard drive with platters the size of a quarter, as a CompactFlash+ module for digital cameras and other handheld devices.

Never content with industry standards, Sony has designed its Memory Stick cards to compete head-to-head against SM and CF. Similar in capacity and pricing to SmartMedia, Memory Stick works in a broad range of Sony devices and only Sony devices. However, Sony's MVC-CD1000 (see the Picture Perfect article in this issue.) is one of the first to use 3-inch CD-R (CD-recordable) media for storing camera images. These discs will hold over 150 2.1MP images but can only be written to once. Lastly, some older Sony Mavica cameras still use 1.44MB diskettes as a storage medium, but these are quickly dying out.

The lowest-end cameras may not have removable memory at all, using instead 4MB or so of fixed memory. This may be fine for taking small product shots for a catalog or something similar, but such designs will quickly prove inadequate for traveling or high-resolution work.

Ergonomics. Almost universally ignored as a buying consideration, camera ergonomics will not only affect your enjoyment in using the camera but may often make the difference in getting or missing an important shot. Ergonomics means more than just being able to hold the camera for long periods without discomfort. More importantly, it refers to the positioning of camera features. When you look through the viewfinder, is your thumb poking you in the eye? Are there rubberized grips for the fingers of your right and left hands so you can hold the camera firmly? If you want to be able to shoot one-handed, can your thumb and index finger easily reach all necessary controls? Are buttons well-labeled and easy to press?

Factors like these are why we strongly suggest using a camera before buying it. No spec sheet in the world will tell you if a camera fits your hands well and is compatible with your own level of dexterity. If you're the kind of user who wants to make manual settings adjustments while shooting, such considerations will be especially important.

Manual settings. Novices and point-and-shooters will often (and rightfully) leave their cameras in the automatic mode, where factors like focus and exposure are all handled on-the-fly by the camera. However, more sophisticated users may want to control a very limited focal range, emulate various ISO (International Organization for Standardization) film speeds (good cameras will handle at least ISO 100 to 400), adjust for artificial lighting conditions, or dramatically overexpose for a certain types of artistic effect.

Nowadays, most advanced cameras offer a full range of manual controls. Entry-level units offer few if any. Intermediate cameras fall somewhere in between, so if you're agonizing over cost versus features around the $500 point, pay extra close attention to the manual settings because this is where you're likely to see the most difference between vendors offering apparently similar models. If you're used to shooting an SLR film camera, you'll want and use lots of manual control.

Naturally, there are plenty of lesser considerations. For example:

�Does the camera include a "hot shoe" for mounting more robust, external flash modules for those all-important ambient shots?

�How large is the LCD (liquid-crystal display) screen, and is it viewable in sunlight?

�Is the bundled photo transfer and editing software user-friendly and feature-rich?

�What is the lag time between when you depress the shutter button and when the camera actually snaps the picture?

�Does the camera offer a rapid-shooting "burst" mode? If so, what is the duration between shots and what resolutions are available in burst mode?

�What is the camera's warranty? Can units be serviced locally? If not, what is the vendor's proven track record for turning around service repairs?

You'll want to have the camera in your hands and feel out the answers for yourself. Also turn to reliable sources of hardware reviews (including our own at http://www.smartcomputing.com) for help.

There are dozens of cameras to choose from; the task of narrowing down your options is formidable. Your best first step is to take an honest look at your own feature needs. This means not only assessing your photographic skill level but also your computer skill level. How much work are you prepared to do yourself and how much do you need the camera and PC software to take over? To get a better sense of these options, we have examined several of today's hottest cameras in the entry-level, intermediate, and advanced categories in the forthcoming pages.

by William Van Winkle

Terms to Know

CMOS/CCD (complementary metal-oxide semiconductor/charge-coupled device)� The two types of sensor arrays digital cameras use to capture images. CMOS technology tends to be more power-efficient, but CCD yields superior image quality.

compression�The process of eliminating pixels and/or color information from an image in order to reduce its file size. Beyond a certain (often subjective) point, compression begins to visibly impact image quality.

lag time�The duration between when you depress the shutter button and when the camera captures the subject image. Cheaper cameras tend to have longer lag times. Lag times longer than one second can result in missed shots and poor composition owing to movement by the user.

LCD (liquid-crystal display)�Most digital cameras feature two LCDs, the first being a small, black-on-silver window to display camera settings and the number of images still available, and the second being the 1.5-inch to 2.5-inch color display, which acts as an image preview/review monitor.

megapixel�One million pixels, the dots that comprise a digital image.

recovery time�The duration it takes a camera to capture, compress, and store an image so that it can take a new picture. Recovery time is affected by the camera's processor, the type of memory being used, the size/resolution of the image, and whether or not the camera uses a buffer to help "pre-store" images, as do some Olympus models.

resolution�The number of vertical and horizontal pixels that comprise an image. The higher the resolution of an image, the more information and detail the image will contain. However, in situations where low-resolution displays are present, such as on a photo frame or a Web-based photo sharing service, high-resolution images may be both unnecessary and burdensome.

Interrogate Your Salesperson

Anyone can read a box and find out a camera's optical zoom range, megapixel size, etc. Some important questions are not so obvious, however, and you should feel free to grill your salesperson for details. Here are a few questions you should be asking, and the answers you'll want to hear.

Q: How many shooting modes does this camera support?

A: Nearly all digital cameras record images as compressed JPEG files. Higher compression means you can fit more images on a memory card, but it also means you're eliminating detail data from your images. Good cameras will offer several levels of compression as well as one or more TIFF modes, TIFF being a top-grade, uncompressed format. Many cameras now also support "movie" modes, and you should check to see how many frames per second can be captured, and at what resolution. Don't expect a large frame, but 15 frames per second is acceptable quality for movie files in this category.

Q: How much memory does the camera come with?

A: Getting a camera capable of shooting 3.4MP (megapixel) images is great, but if the camera only comes with an 8MB card, you're going to be either a) making a lot of trips to your PC to download the few images that can fit in the card or b) immediately buying higher capacity cards. It's important to factor in the realistic cost of memory if you're examining high-resolution cameras. Check how many images can fit onto the camera's bundled memory card when you're shooting at the highest resolution setting � because you probably will be � and see if the number is acceptable to you.

Q: What lens options do I have?

A: With most entry-level and intermediate cameras, the answer is "none." A few models, though, will offer snap-on attachments for wide-angle shooting, filters, and more. Very advanced cameras offer true SLR-style functionality for removing and swapping lenses. If you plan on doing some fancy photography, look for a camera with at least a few lens options.

Q: Does this camera offer TTL [through the lens] viewing?

A: Very few consumer digital cameras offer this standard SLR feature, although the HP PhotoSmart 912 is one stellar exception. TTL means that when you look through the viewfinder, you're actually looking through the lens, seeing what the CCD sensor is seeing and assuring perfect composition accuracy. When the viewfinder has a separate perspective from the lens, especially if the two are horizontally off-center, this can create a parallax effect. Especially with close-up subjects, parallax will cause you to accidentally overcrop your subjects. The work-around for this problem is to always shoot by using the LCD display as your viewfinder, although this approach will put a heavier drain on your batteries.

Q: What kinds of batteries does this camera use?

A: Most cameras operate on AA cells of some sort. Know that digital cameras, particularly when used with the flash and LCD display, chew through batteries like mad. If you plan on using off-the-shelf alkaline cells, be prepared to buy a lot of them. Rechargeable NiCad () cells are ultimately easier on the wallet and the environment, but they're also the weakest of all battery types in terms of holding a charge. Rechargeable NiMH (nickel metal hydride) cells are more expensive and harder to find, but they last substantially longer than alkaline or NiCad. Li-Ion (lithium-ion) cells are the best and costliest of all. Some vendors make proprietary, disposable Li-Ion packs for cameras, and these may make sense if you plan on doing long shoots away from a power outlet and don't want to hassle with changing batteries. In our opinion, built-in rechargeable Li-Ion packs or rechargeable, removable Li-Ion cells are the best possible options. Any camera in the intermediate or advanced categories should come with some kind of rechargeable battery configuration, including cells, charger, and any necessary cables. Most cameras don't include AC power cables, but this can be a valuable option if you'll be doing a lot of indoor shooting.

Q: How can I get images from the camera to the PC?

A: By now, most cameras offer the ability to connect the camera directly to a PC via a USB (Universal Serial Bus) cable, thus eliminating the need to remove the memory card from the camera. However, not all USB connections are created equal, and some cameras can take substantially longer than others to move the same amount of information. Kodak bundles a CompactFlash reader with many of its cameras, so you need only pop your cards in the reader and start downloading, even if you don't have the camera. Lexar bundles its JumpShot cable with some of its high-speed CF cards, which accomplishes the same purpose. Fuji often includes an adapter that allows you to plug SmartMedia cards into your floppy drive, although we've found this to be a relatively slow method. The point is that you don't want to be locked into having to keep your camera and PC together all the time. Bundled readers can be a strong plus.

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