Digital Camera 10x Zoom

A digital camera 10x zoom, as the name suggests, is a compact camera with a lens that can optically zoom in on, and hence magnify, the subject by 10 times. These are fixed-lens cameras in that the lens is an integral part of the camera and cannot be removed and replaced, as can be done with a digital single lens reflex (SLR) camera.

Because of their strong magnifying power, you'll also hear people refer to digital cameras with 10x (or more) optical zoom lenses as "super zooms" or "ultra zooms".

Optical v Digital Zoom

With digital zoom, there is no optical magnification at all; the image recorded on the camera's sensor remains the same size, but the camera's software "magnifies" the image by taking just a portion of it and then digitally enlarging it by adding pixels (called "interpolation). This causes a loss of quality, and a camera's "digital zoom" specs can be safely ignored.

If you have to blow up a portion of the image, better to do it with an image editor on your computer.

Prime v Zoom Lenses

This is made possible by movable groups of lens elements within the lens that allow you to alter its focal length.

This ability to set infinitely variable focal lengths between the limits of the zoom range makes these lenses incredibly flexible as you can adjust the lens to show more or less of the scene. When composing your shot, this is a huge advantage as you can make small adjustments to the framing of the picture without having to move the camera.

With a 10x optical zoom digital camera, this flexibility is further enhanced as the range of available focal lengths is huge, from wide angle to long telephoto.

When photographing a building, for example, you could include the whole building in your frame at the lens's widest setting, then zoom in on specific features, including close-up detail. Think how useful this is, particularly when you can't simply walk closer or further away, as is often the case with travel photography in urban settings.

On a compact digital camera with 10x zoom lens, the two extremes vary, but will usually be something like the equivalent of a 35 to 350mm, or 27 to 270mm, on a 35mm camera.

"Equivalent" Focal Length

Because compact digital cameras have tiny sensors - much smaller in area than a 35mm negative - the actual focal length of the lens is correspondingly much shorter than on a 35mm camera. So, for example, the Canon 10x optical zoom lens on the Canon PowerShot SX120IS camera has an actual focal length of 6 to 60mm! But that is meaningless to most people, so the "equivalent" focal length of 36-360mm is used instead.

In most cases you can simply ignore the actual focal length - if it's even mentioned - and concentrate on the equivalent focal length. This is useful information as it indicates the two extremes of the lens, from wide angle to telephoto and, depending on your preferred photographic subjects, could be a determining factor when selecting a camera.

The Canon Powershot mentioned above starts at 36mm, which is not very wide, and some people might prefer something that starts at a wider focal length, as in a 28-280mm 10x zoom lens. On the other hand, if you want maximum enlarging power, then the Canon's 360mm maximum focal length will better suit your needs.

If you're likely to be taking mainly landscapes, interiors, and group shots, then you should opt for a digital camera with 10x zoom that offers the widest possible angle of view (28mm or wider). If you're more interested in photographing sports or wildlife - or capturing great candid shots while remaining unobtrusively in the background - then go for the most "pulling" power, like 350mm or more.

Digital Camera 10x Zoom Advantages

• Great flexibility, allowing you to shoot photographs from wide angle to telephoto and so make the most of virtually any picture opportunity.
  
• No need to carry a bag of lenses, as would be necessary to cover the same range of focal lengths with a digital SLR.
  
• Relatively light and compact when compared to a digital SLR, so are easier to transport, store, and carry around.
  
• Fixed lens means no dust or debris can gather on the sensor as invariably happens when changing lenses on digital SLR cameras.
  
• Cost. Although these cameras don't fall in the budget category because of their sophisticated lenses, they're still substantially cheaper than a digtal SLR plus two or three lenses.