Optical Zoom vs. Digital Zoom - The Difference

When selecting a digital camera based upon its zoom feature, don't just look at the x2 / x4 / x6 and think that's all there is to it. Digital cameras come with two types of zoom capabililty, and you will find that optical zoom is the more important of the two. So base your decision mostly on how much optical zoom a camera has.

What Is Optical Zoom?

In technical terms, optical zooms are constructed to allow a continuously variable focal length, without disturbing focus. This is performed by using a combination of lenses that magnify the image prior to being registered at high resolution.

In layman's terms, optical zoom is actually focusing in on a smaller area with a sharper focus in the same way your eye does, thus the 'optical' reference. Optical differs from digital in that digital zoom only takes a smaller area of the picture you are looking at and forces it to fit the full viewing screen.

Digital does not focus in as it zooms closer and closer. Optical does.

While the digital zoom only changes the presentation of existing data, the optical zoom actually augments the image collected by the sensor. Optical zooms are clearly superior to digital zooms, and should be the first thing you look for in purchasing a digital camera.

What Is Digital Zoom?

Digital zoom is simply cropping a portion of a captured image and then resampling it back up to full resolution. The most notable difference between digital and optical zoom is that no additional image detail is gained by using digital zoom.

Digital zooms lower image quality. Choose a camera with an optical zoom if image quality is important. Digital zooms should be used only when image quality is not important.

How Much Optical Zoom Do You Need?

As with megapixels, how much optical zoom capability you should get really depends upon you and the reasons you are taking pictures. If you just take photos at home, then 2x optical zoom is probably fine. If you are regularly taking photos outside and need to focus very far away, you should pick the highest optical zoom you can afford.

Be aware that more optical zoom equals a higher price for your digital camera. Currently, you can get a 1 megapixel digital camera with x2 optical zoom for around $100. A higher-quality digital camera with 3 megapixels and x6 optical zoom can be found in the $250 to $500 price range.

With megapixels and optical zoom out of the way, the next major feature is how many photos your digital camera can store, or its memory...

Next Section > Camera Memory