Today's advanced amateur digital cameras are reminiscent of film rangefinder classics such as the Leica M6. Whether classic or modern, these cameras appeal to serious photographers who want to pack as much quality and control as possible into a camera that hangs lightly around the neck.
Advanced amateur cameras feature high-quality zoom lenses, 6-megapixel or higher image sensors, and an array of controls that will help you meet just about any photographic challenge. You can usually build an entire outfit, including flash and accessories, for less than $1,000.
These tools are for photographers who like the art and science of photography, so in this section I'll spend a little more time talking about various aspects of these cameras, to help you understand their capabilities.

Battery types

If your camera came with alkaline AA batteries, use them for testing, then replace them as soon as possible with rechargeable nickel-metal hydride (NiMH) batteries, which last much longer than alkalines and will save you lots of money over time. It's always good, however, to keep a fresh set of alkalines handy in case your NiMHs run out of juice while you're away from the charger. Another good practice is to have two sets of the rechargeables, so one's always ready to use—they're a little expensive at first, but much cheaper than buying new alkalines over and over.
Lithium-ions are very popular with major camera makers such as Sony, Nikon, and Canon. Most of these cameras come with their own proprietary battery and its matching charger. Lithium-ions typically have great capacity and hold their charge for a long time, but you might want to buy an extra battery—you can't use readily available alkalines as a backup.
Another thing to keep an eye out for with lithiums is how you charge the battery. I recommend using a separate charger (the more compact the better), instead of having to recharge the battery by plugging a power adapter into the camera. Obviously, you can't pop in a spare battery and go out and take pictures if you need to plug your camera into a wall socket to recharge.

Diopter adjustment

The diopter adjustment allows for manual adjustment of the optical viewfinder to best suit your vision. When I was younger, I could care less about this feature. These days I'm very thankful for it, because it's hard to look through optical viewfinders with glasses on.

Exposure metering options

All digital cameras have some type of exposure meter, but many models have more than one pattern for measuring light. The three most common patterns are:
Center-weighted The meter measures light levels in the entire picture area, with extra emphasis placed on subjects in the center of the frame.
Evaluative The image area is divided into sections (usually six or more), and light is measured in each section. The camera then "evaluates" each section and matches the overall pattern to data stored in its computer system. The resulting camera settings are determined by how the pat tern and data match up.
Spot To determine the exposure, light is measured in only the center area of the viewing area, usually indicated by brackets. Everything else is ignored. Spot metering is helpful in contrast lighting situations that might fool other metering patterns.
Advanced cameras may include all three of these metering patterns, while more basic models may rely on only the evaluative pattern.

Hotshoe

The hotshoe provides a connection for an external flash and other camera accessories. The metal contacts allow the camera to communicate with the flash to provide advanced features such as dedicated exposure control. Often, you can purchase "dedicated flash cords" that enable you to retain communication between camera and flash, but move the two apart for more lighting options. One end of the cord connects to the hotshoe, and the other connects to the base of the flash.

Image stabilizer

Often referred to as "anti-shake technology," the image stabilizer helps you capture sharp pictures in low light. When activated, the camera actually compensates for the minute movements you make during exposure. Camera shake creates a picture that looks "soft" and not quite in focus. By counteracting those minute movements, image stabilizers help you record sharper images.

Infrared sensor

The infrared sensor is primarily used to communicate with the remote control release for cameras that have that capability.

LCD viewfinders that swivel

Most compacts and DSLRs have LCD viewfinders that are fixed-mounted to the back of the camera. An advantage you often find with advanced amateur models is an LCD monitor that swivels away from the back of the camera. This enables you to hold the camera at a variety of angles and still compose the picture—perfect for taking "over the head" shots at a parade!

Memory card options

The most popular memory cards are CompactFlash (CF) and Secure Digital (SD), but Sony Memory Stick (MS), IBM MicroDrive, MultimediaCard (MMC), and the xD-Picture Card introduced by Fuji and Olympus are also widely used. Some older cameras use SmartMedia (SM) cards, which are still available but are not as easy to find as they used to be. That technology is being replaced by xD-Picture Cards and SD cards, which are smaller and have more capacity.
The type of memory card your digicam accepts isn't as important as its capacity and performance. Most cameras ship with starter memory cards that hold only 16 or 32 MB. These are fine during the learning phase, but once you're ready to take your camera on vacation or photograph your daughter's birthday party, you'll need more memory. Some cameras don't even provide a memory card in the box. Make sure you have a compatible one on hand, or you'll be sorely disappointed.
Another thing to consider when shopping for memory cards is the speed at which they read and write. "High-speed" or "ultra" cards can perform at many times the speed of "standard" cards, but much of this benefit depends on the sophistication of your camera's electronics. If you have a high-performance camera, you should consider having at least one high-speed memory card. Standard cards should perform just fine for basic models.

Remote release

The remote release allows firing of the camera from distances of up to 15 feet. Some remote releases also allow you to operate the zoom lens. For best results, point the sensor on the remote release at the infrared sensor on the front of the camera.

Zoom lenses

Camera makers tend to list two sets of numbers on the barrel of the lens, or on the body near it. The first set is usually followed by "mm" (which stands for "millimeters") and looks something like this:
5.4–10.8mm or 7–21mm
These numbers represent the zooming range of your lens. Most consumer digital cameras have a zooming range of 3 x, such as a 7–21mm lens.
If you're familiar with 35mm photography, you can translate those digital camera focal lengths into terms that are easier to understand. For example, a 7–21mm zoom lens in the digital world is the rough equivalent of a 35–105mm lens on your traditional SLR.
There is no magic formula you can always apply to translate digital focal lengths to traditional 35mm numbers, though, because the relationship is determined by the size of the camera's sensor. Camera manufacturers will usually tell you what the 35mm equivalent is. Sometimes, as with digital bodies that accept 35mm lenses, they will tell you the size of the sensor and its relationship to your existing lenses. The Canon 20D, for example, has a sensor that's smaller than 35mm film. The result is a focal length factor of 1.6x, so your standard 50mm lens becomes an 80mm telephoto when attached to the 20D.
A general rule of thumb is that there's a 50% increase from film to digital: a 14mm nominal focal length lens is around 21mm on a digital SLR. The exceptions are high-end models such as the Canon EOS 1Ds, which have a "full size" sensor (meaning that the lens focal lengths remain the same as in 35mm photography).
The second series of numbers usually looks something like this:
1:2.8–4.0 or 1:2.0–2.5
These numbers represent the maximum aperture of the lens at the wide angle and telephoto settings. Aperture determines the amount of light that can pass through the lens to the camera sensor. Wide apertures, such as 1.8 or 2.0, allow a lot of light to pass through the lens and are therefore better in low-light conditions. Narrower apertures, such as 5.6 or 8, allow less light through the lens and are less desirable for low-light shooting.
When thinking about the best compact or advanced amateur camera for you, keep in mind that you'll have to live with the aperture and zooming range of the lens for the life of the camera. Unlike DSLRs, where you can change the lens, compact cameras have the lens permanently mounted to the body.
Some cameras do provide accessory lenses that mount on the end of the existing glass. These work relatively well, but they are cumbersome and not many options are available.
For advanced amateur models, I recommend a zooming range of at least 5 x; more is better. Also pay attention to the wide end of the range. Get a lens that gives you the 35mm equivalent of 28mm on the wide end. Digital cameras are notorious for not providing you with as much wide-angle coverage as film cameras.
Advanced amateur cameras provide amazing capabilities in a portable package, and often for less than comparable DSLR kits. If you can live with a lens fixed to the camera body, and are willing to sacrifice a bit of high-speed performance, cameras in this class should satisfy the needs of the most critical of photographers.