Digital Zoom: A Beginner's Guide

Digital zoom is much disputed in terms of its usefulness. Here, we take a look at the pros and cons of digital zoom, where it can help, and where it is more of a hindrance.

Most compact cameras have some form of digital zoom and it usually kicks in when your camera reaches its optical zoom limit.

Digital zoom works by selecting the middle of the image that the camera sees and zooming in on it – but because the lens of the camera can't extend any more, it does this by magnifying the existing pixels, and cropping the image down before resizing it to the original aspect ratio. Because the pixels are magnified, the image becomes more grainy and pixellated the more you digitally zoom in. So, the more you zoom in, the more quality you lose.

Digital zoom really only comes in to use when you are desperate to get closer into an image, and the only way to make the subject recognisable is to use digital zoom.

No Zoom	Optical Zoom	Digital Zoom
Wide Angle | 1/1000 sec | f/3.1 | 4.9 mm | ISO 80	Full 10x Optical Zoom | 1/500 sec | f/5.6 | 48.5 mm | ISO 80	Digital Zoom | 1/500 sec | f/5.6 | 48.5 mm | ISO 80

The obvious con with digital zoom is that you are losing precious quality. If you want to get great prints from your shots, digital zoom will not help you. It increases noise, makes the image less sharp and means that the slightest movement on your part blurs the image.

Wide | 1/550 sec | f/4.0 | 4.2 mm | ISO 100	Full 30x optical Zoom | 1/300 sec | f/6.4 | 126.0 mm | ISO 100

Overall, digital zoom should only really be used as a last resort. If you want more optical zoom, consider investing in a Digital SLR or ultra zoom bridge camera. This way, you can use lenses of various focal lengths which will allow you to get closer to your subject.