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Cut Through the Hype and Make the Right Digital Camera Comparisons

2008-06-13来源:

There are soooo many choices. With all the styles and features, and prices are all over the map, digital camera comparisons can be mind-boggling. Pixels, memory, optical and digital zoom, camera size and cost are all factors to compare. So how do we sift through all the hype and find the best digital camera?

First step: Identify your primary prerequisites. A camera is normally something we will own and use for several years. To find the best camera for your needs, certain basic decisions need to be made before you start comparing features. These include:

  • Suitability - do you want a camera for candid snapshots or serious photography?
  • Quality - compare quality of both the camera and the photos it takes.
  • Size - models to compare include miniature, compact and full-sized cameras.
  • Price - compare cameras in a price range set by your needs and budget.
  • Second step: Compare specific features?

    Compare Pixel Quantity and Quality

    In general, more is better. Each pixel is a tiny square of light and color. Digital photos can be compared to mosaics - more pixels mean smaller squares and sharper pictures. But comparing pixel quality is just as important.

    Tiny photodiodes in an image sensor is the technology that creates the pixels. The sensor functions as the camera's eye and some digital camera sensors measure only a few millimeters. Other cameras with larger sensors usually have better quality diodes, resulting in sharper, clearer pictures.

    Don't Skimp on Memory

    A single digital photograph can require several megabytes, though file type, compression rate and subject matter all affect file size. Most digital cameras don't have nearly enough built-in memory, so when doing a digital camera comparison plan on buying more. A general rule of thumb is to have at least 256-512MB of memory - more if taking high resolution or a lot of photographs.

    Check memory compatibility when you compare digital cameras. Compact flash is the most universal and cost effective. MultiMedia cards are smaller and also work with other devices. Secure Digital are MultiMedia cards with an added write-protect switch. xD Picture cards are small and adaptable to most compact flash applications. Others such as Memory Sticks, SmartMedia and MicroDrives have limited applications, but may be best for the camera you want.

    CCD Compared to CMOS

    Charged Coupled Devices (CCD) and Complementary Metal-Oxide Semiconductors (CMOS) are digital camera image sensors. They can be compared to the shutter and film in a traditional camera.

    Developed in the mid 1970's, the CCD is the heart of most digital cameras. With millions of light collecting cells, its image perception can be compared to the human eye. The CCD sensor's quality makes it the preferred choice for high-end digital cameras.

    CMOS sensors were developed in 1998 with technology comparable to processor chips. Advantages are lower cost, less power required and multi-tasking ability. Disadvantages include signal noise and resolution issues. As the technology improves, CMOS sensors will make digital cameras more affordable and be the best choice for entry level cameras.

    Beware the Zoom-Zoom

    In your comparison of best digital cameras, be aware of the zoom issue. Digital zoom isn't much more than a marketing gimmick. It crops the image on the sensor, reducing total pixels and degrading resolution. Optical zoom magnifies the image before the sensor reads it, retaining full resolution.

    Other important features?

  • Shutter lag - how quickly can you take another picture? Should be a second or less.
  • Start up time - when turned on, the camera should be ready within a couple of seconds.
  • Manual override - allows you to adjust exposure and focus settings.
  • Auto-focus - should be nearly instantaneous in most lighting conditions.
  • Digital camera ratings often discuss other features, but getting these right will enhance the enjoyment of your digital camera experience for years to come. Find more detailed comparisons at our Digital Camera Technology page.

    Digital cameras information from A to Z: camera types & features, how they work, accessories, photo printers, comparisons and more - plus digital photo processing tips and info at A-Z Digital Cameras.com, Your Complete A-Z Resource for Digital Cameras, Accessories and Information.

    This article may be re-printed in its entirety, with no changes and this resource box included. 2005 A-Z Digital Cameras All rights reserved