Digital camera buying guide. What we need to look at.

What should I start with?

Buying a digital camera is a good idea - you save your memories. At the same time this task can be a bit complicated. There are hundreds of cameras available at many different types of retail outlets (online and in traditional stores), with prices ranging from $75 to several thousand dollars. Some cameras are small enough to fit in a shirt pocket. Others are large and can weigh up to two pounds. Some are easy to use. Others look like you need an engineering degree to operate them. And almost all are advertised with abbreviations that can be cryptic and confusing for the novice. In this digital camera guide, we aim to help you overcome some of this confusion.

So what is a digital camera?

The first step is to understand what a digital camera is. With a film camera, an image is formed by collecting light from a particular scene or subject and focusing on film, which reacts chemically when struck by light and is said to "capture" the image. What makes a camera "digital" is that, instead of film, it has an image sensor that reacts to light by sending out electrical signals.

The camera takes the information from the image sensor and processes and stores it as a collection of pixels in a digital file, usually on a memory card inside the camera. Although the actual process is more complex than that, in essence it is how a digital photo image is made. It's essentially made up of thousands and thousands of tiny dots, or pixels.

high zoom digital camera

1. What are megapixels?

When you collect a million pixels, you have a megapixel. The number of megapixels tells you how many pixels the image file has. A camera that captures 8 million pixels, for example, is called an 8-megapixel camera. The number of megapixels a camera features can also help to determine the size photos you can print or the amount of cropping you can do. For example, a 6-megapixel camera may be enough for snapshots, but if you want to print poster-size images or crop heavily, 8 megapixels (or greater) is more suitable.

A 6-megapixel camera might be all you'll need because higher resolution doesn't necessarily produce better prints. Lenses and other factors affect quality too. But most cameras today have at least 10-megapixel sensors. The size of the sensor, and the size of each individual image sensor element, which corresponds to pixels, can affect photo quality. But remember, the number of megapixels alone doesn't determine the quality of a digital camera's images.

Types of digital cameras

Our Ratings are divided into two main categories: Basic cameras, are simple point-and-shoots with just the features needed for routine shots, and advanced cameras, which are feature-laden cameras that include sophisticated point-and-shoot and models that let you change lenses. Note that all point-and-shoots, whether basic or advanced, include cameras with lenses built into the camera (that is, non-removable).

Our basic camera category is divided into three subcategories: subcompacts, compacts and superzooms.

Subcompacts fit in a pocket, are lightweight but generally have few manual controls. A few include nontelescoping zoom lenses, and others have zooms as high as 14x. Compacts are a bit larger, and often have more manual controls than subcompacts. They can also be among the most inexpensive cameras available.

Beware the sales pitch

You can't always depend on sales staff to help you to choose the right camera. Readers indicate that the quality of in-store help is all over the map. Indeed, when our reporter shopped at mass merchandisers, as many consumers do, a member of the sales staff told him that there was no difference between digital and optical zoom (optical is far more useful). Another couldn't explain the differences among mechanical, optical, and simulated image stabilization (optical and mechanical are superior).

Also, despite the prevalence of 10-, 12-, and 14-megapixel cameras, 6 megapixels is all the resolution most people need. If you often crop or drastically enlarge your images, get at least 8 megapixels. Higher resolution doesn't necessarily produce better prints, so don't let a saleswoman push a camera solely based on its megapixel count.
Shop by brand

Before diving into specific models, consider some characteristics by brand, culled from our years of digital-camera tests. For example, Fujifilm offers image sensors with proprietary technology that produce high image quality at high ISO settings. Kodak emphasizes simplicity and ease of use. Canon, Nikon, and Olympus offer full lineups for every type of user. Casio specializes in ultra-slim models. Samsung offers cameras with high styling and multimedia features. Panasonic uses image stabilizers and Leica lenses throughout its line. Sony often uses Zeiss lenses, a brand well known in the camera world.
Try it out

The smallest, lightest models aren't necessarily inexpensive cameras. And the biggest and heaviest aren't necessarily found at the high end. If possible, try cameras at a store before you buy. That way, you'll know which one fits your hands best. In our tests, some of the smallest didn't leave much room even for small fingers.
Keep your other cameras in mind

If you own a film camera with interchangeable lenses, you can often use the lenses on digital SLRs of the same brand. But there are exceptions. For example, some new Nikon bodies only operate autofocus on its AF-S or AF-I lenses.
Forgo the extended warranty

Overall, digital cameras have been among the most reliable products in our subscriber surveys. About 4 percent of those bought from 2006 through 2010 have been repaired or had a serious problem. Yet in our latest survey, 60 percent of camera buyers were pitched an extended warranty in stores, and 16 percent of those bought one. We don't think it pays for most consumers.