Zoom Functions on Digital Cameras

28 October 2014

As a printer of photographic images, I am frequently amazed by the lack of understanding cameras users have when it comes to optical zoom versus digital zoom.

This is something that has a direct bearing on the end quality of an image, so I decided it was time to remind everyone how zooms work.

Optical Zoom. This is where the optical cluster of a zoom lens changes its configuration to alter the angle of view as the zoom ring is turned. In addition, the entire area of the sensor is used to capture the resulting image, meaning clear, sharp images for me to print and satisfaction for you, the photographer, when it comes to hanging the result on your wall.

Digital Zoom. This is where the camera uses an ever decreasing portion of the image area, in effect it is cropping the image and reducing the resolution by concentrating on a smaller cluster of pixels. The result is a loss of definition and in most cases it results in heavy pixelation. The image acquires a grainy look.

This type of zoom is used in iPhones, iPads, Smartphones and as an extension of the optical zoom in compact and prosumer cameras. 

To ensure you get the best quality out of your camera, make sure the digital zoom is turned off. In all other devices, just don't zoom. With such a small sensor, they can't possibly produce a decent image if zoomed.

I hope this has been useful and I look forward to receiving your quality images to print so that you can show off your talent.