Computeruser’s digital- camera buying guide.
Just as the introduction of photography didn’t kill painting, digital cameras won’t replace silver-based imaging any time soon. At least that’s what I thought when I started writing this piece; now I’m not so sure. Photography did replace another medium for certain applications, such as portraiture. Similarly, digital imaging is replacing another medium for certain applications, especially when delivery time is critical. Because they have a natural element of fun, digicams are also fast replacing their silver-based equivalents in the pockets, purses, and gadget bags of tech-savvy amateur photographers. You make a photo, look at it on the LCD preview screen, and decide if you want to make another. We’re growing a generation of digital children who expect cameras to show them pictures right now. Sure, we’ve had Polaroid prints for 60 years, but to Pokémon kids, digital images are more real because they’re on TV.
Smile, you’re on digital camera!
Digital cameras have two major and obvious advantages over their film-based siblings: They don’t require film or any kind of photochemical processing, and there’s no waiting. After creating images with a digital camera, you download them onto your computer, where they can be enhanced, e-mailed, or output using a photo-quality inkjet printer. Some videocentric digital cameras let you view your freshly baked pictures on any television set that has camcorder input jacks.
Digital cameras fall into three major categories: point-and-shoot, field cameras, and studio cameras or backs. The first group is the digital equivalent of the familiar point-and-shoot 35mm camera, in which ease of use and low cost ($300-$1,000) are important. The people who use these lowest-priced digital cameras include everybody from professionals who paste photographs into desktop-published documents to parents photographing soccer practice. When combined with online image sharing sites, such as PhotoIsland, digital point-and-shoot cameras do a great job of letting family members, who may be scattered all over the globe, share special moments.
The second group includes digital field cameras, many of which are based on conventional SLR 35mm bodies from companies such as Nikon and Canon. Since digital field cameras often use the same lenses as film-based cameras, they are easily integrated into an existing camera system. Prices begin at slightly more than $2,000 for entry-level cameras such as the Canon’s EOS D30, making digital field cameras a popular choice for location photographers on tight deadlines.
The ultimate in image quality comes from digital studio cameras and backs, which are used by advertising photographers to create photographs from art directors’ sketches. Some of these backs must be connected directly to a computer, but no matter how they’re tethered, these expensive cameras and backs deliver the film-like resolution needed for advertising, large prints, and catalog work. These high-resolution cameras also have five-figure price tags that make them unattainable even for some pros, but the same downward price pressure affecting point-and-shoot and field cameras are sure to affect studio cameras and backs. The only question is when.
What to look for when shopping
There are three major factors to consider when shopping for a digicam: The first is the camera’s optics. It doesn’t matter how good the electronics are if the lens isn’t up to the task. Second, consider the imaging chip. Digital still cameras use CCD or CMOS chips to capture light and convert it into images. The size and type of chip will determine image quality. Next is the type of compression. All digicams use some kind of JPEG (Joint Photographic Experts Group) compression to store images. JPEG techniques compress an image into discrete blocks of pixels, which are divided in half using compression ratios that vary from 10:1 to 100:1. The greater the compression ratio, the greater the loss of quality you can expect. Lower compression produces fewer, better-quality images. The highest image quality option is no compression.
A digital photograph’s resolution is measured by the width and height of the image measured in pixels. The higher an image’s resolution, the better the visual quality will be. Some manufacturers overstate their camera’s capabilities and sometimes advertise an interpolated resolution. Just as when evaluating scanners, you should always compare the “raw” or optical resolution of a camera when making a purchase decision. How much is enough? It depends on how you plan to use the camera, but one rule of thumb is that anything more than three megapixels will deliver enough quality for the average computer user, though there are always exceptions (see sidebar, “Picks of the paddock”).
A digital camera’s light sensitivity can vary from moderate to quite high, letting you shoot in very dim situations. You can compare it to film’s sensitivity from an ISO rating of 100 up to 1,600. Some digital cameras have controls that let you change this light sensitivity, while some low-end cameras let you change settings only by using software that accompanies the camera.
As in silver-based photography, there’s no substitute for good lighting; but along with higher light sensitivity comes lower image quality. This shows up in reduced contrast, image noise, and muddy color. When used at boosted ISOs under low light conditions, almost all affordable digital cameras produce noise that looks like film grain. The use of a Photoshop-compatible plug-in such as Grain Surgery can help reduce noise and increase image quality. Some inexpensive digital point-and-shoot cameras don’t have a built-in flash, and higher light sensitivity will help when the illumination is low. Only a few pro-level field cameras offer built-in flash, but they are usually compatible with the sophisticated shoe-mount flashes camera manufacturers offer as options.
Some cameras substitute a color LCD panel for an optical viewfinder, while others have both. Making pictures with a LCD viewing system entails an extended-arm shooting technique, which you may like or hate. Nevertheless, it’s fun to use the built-in screen to preview images and delete the ones that didn’t turn out so well. Because the only images stored will be the ones you like best, the number of images a camera can store is effectively increased. On the flip side, increased use of LCD panels tends to lessen battery life.
The number of images a camera can hold is based on the type of storage it has and the way it manages images. There are two basic kinds of image storage: internal memory and removable media, with some cameras offering both. When a memory card is filled, you can pop another one in, much as you would change a roll of film. Or if you carry a laptop computer, you can download images as you fill up the card. The most common digicam connection is USB, but field cameras may use the faster FireWire (IEEE 1394, aka iLink.) The best transfer solution is a memory card reader that makes it possible to download image files directly from the camera’s storage media. Olympus’s FlashPath adapter lets you insert SmartCards into a floppy disk-like device and transfer images through your computer’s floppy drive. Sony offers a similar adapter for Memory Stick users that’s much faster than FlashPath.
Some other considerations, such as fixed focal length versus a zoom lens, are similar to decisions you have to make when purchasing a conventional camera. Be sure to inquire about lens compatibility before assuming your existing lenses will work with an interchangeable-lens digital field camera. Lenses with maximum apertures less than f4 can cause vignetting, so you may not be able to use every lens you own. Be aware that the format of the CCD image chip may be different than the standard 35mm 24-by-36mm format. This means that the effective focal length of your existing lenses will seem different–longer-than they really are. Since the physical size of the CCD chip varies with each camera, check your user’s guide for focal-length translations.
A camera with video-out capability can be valuable since it allows you to preview images on your television or even present them as a “slide show.” Many TVs have front-mounted video-in jacks, making it easy to hook up your digital camera. That’s why it’s a good idea to make sure you have all of the cables you need before walking out of the store with a camera-even if you have to make a separate purchase.
Avoid buyer’s remorse
If you buy a digital camera just to save money on film and processing you may be in for a surprise. One of the biggest differences between film and digital photography is start-up cost. After you buy a film camera you can take the film to any minilab and they’ll gladly make prints for a modest charge, but when you purchase a digital camera you also buy in to the concept of the digital darkroom. For some computer users this may just mean a few hardware or software upgrades along with a new peripheral or two, but if you’re starting from scratch, MacWorld magazine estimates the cost can go as high as $6,500, depending on your digital imaging goals.
I don’t believe it has to cost that much. Recently, I’ve been using a budget-priced Windows XP computer that has more features and better performance than some expensive systems. eMachines’ T4155 computer uses a 1.5GHz Intel Pentium IV processor, has 256MB RAM, a 12X CD-RW drive, 12X DVD drive, 60GB hard drive, fax/modem, and an Ethernet network card for DSL/cable Internet connectivity. The T4155 costs less than $800, and after adding a $149 Epson Stylus Photo 820 inkjet printer, the system cost is less than $1,000.
Because manufacturers see them as consumer electronics rather than cameras, digital cameras have a shelf life similar to that of camcorders–about six months. This constant rollout of new models creates confusion and indecision in more than a few users, and may be stalling penetration of digital cameras into the traditional film market. Buy it on Monday and the company announces a new model on Tuesday with higher resolution, more features, and a cost of $200 less than the one you just bought. There is no cure for the kind of buyer’s remorse that’s created by the unrelenting rollout of new digital-camera models, but being informed and making a decision based on real-world needs and budget will minimize post-purchase angst. The most important steps before making a purchase are deciding what features are important to you and matching your needs and wallet to what’s available.
Here’s a brief checklist of what to do when shopping for a new digital camera:
Shoot a few test images in the store and take them home on removable media. (Tip: Bring your own memory card even if you have to borrow one from a friend.) Make a few prints on the same output device you plan on using and evaluate the results. If you have an understanding sales person, you may be able to print an image or two using one of the store’s photo-quality printers. (Tip: Bring your own photo-quality paper, just in case.) If neither of these alternatives is available, buy it and try it. Many computer superstores allow you to return equipment for a full refund within a reasonable time, but make sure to get that policy in writing.