by Aaron Hunt

Created on: June 04, 2010

Modern digital cameras offer more flexibility and more features at a given price than ever before.  One area that is often misunderstood is the amount of zoom a camera offers.  There are typically two numbers presented – optical zoom and digital zoom.  Higher zoom allows photographs of subjects from farther away in what appears to be a close-up shot. 

Digital zoom essentially crops the image in the camera.  The same effect can be achieved with image editing software, but by using digital zoom you lose the image quality permanently.  In a six megapixel camera, digital zoom typically limits the image to four megapixels.  With a twelve megapixel camera, it may be limited to eight or ten megapixels.  What this means is that by using digital zoom the camera is not capturing images at full resolution and image quality will suffer. 

Optical zoom moves the image closer by adjusting the length of the lens.  That is why when the camera zooms in the lens moves outward.  The lens operates as a magnifying glass.  By utilizing optical zoom, maximum image quality can be maintained.  Optical zoom is the same concept used in 35mm film cameras for decades and is still used by professional photographers world wide. 

 In the event that the optical zoom is insufficient, the image can be edited using software.  Many digital cameras are now offering 20x or even 30x optical zoom.  Just a couple years ago 16x digital zoom was a high number.   With optical zoom numbers on the rise, digital zoom is touted less frequently.  It is still wise to verify what type of zoom is being offered when deciding which camera to purchase. 

One additional consideration on zoom is to evaluate exactly what the 10x zoom or 20x zoom number represents.  The 10x refers to the ratio of minimum to maximum focal length.  Therefore, one brand of camera may offer a 10x optical zoom of 24mm-240mm while another may offer 35mm-350mm.  While that may not seem significant, the former will be much better at shooting landscapes while the latter may be better for sports and long-distance shots.  

Most importantly, consider what type of photos will be taken.  A large amount of zoom doesn’t help if the camera is too bulky or can’t shoot indoor photos well.  When shopping, ignore the digital zoom and focus on optical zoom.   Most people find they rarely use the digital zoom once they have experienced the quality of a nice optical zoom lens.                 

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