Digital or Optical zoom for Security Cameras
When shopping for security dome cameras with zoom
capabilities, the question I ask myself is which is more important; digital or
optical zoom? When speaking of surveillance cameras you want to get
“close” to a subject from a fixed camera position. The zoom control on your
digital camera will let you get “close” enough to capture that bigger image. It
will also let you zoom out to include a wide angle of view.
What
is optical zoom?
Optical zoom is a true zoom lens, which is physically extend to magnify your
subject. A motor controls the lens movement.
What
is digital zoom?
Digital zoom is simply some in-camera image processing, basically decreasing
the apparent angle of view of a digital photographic or video image. To make the cropped area
bigger, digital zoom makes up, or interpolates, pixels to add to the image,
which may give less than satisfactory results.
Zoom meaning the ability to make something distant appear closer.
Basically it’s a ratio of the longest and shortest focal length.
A 17mm (Wide) to 50mm (Tele) lens would be roughly 3x zoom. (50/17 = 2.94)
However a 70mm (Wide) - 200mm (Tele) lens would also be a roughly 3x zoom. (200/70 = 2.86)
A 17mm (Wide) to 50mm (Tele) lens would be roughly 3x zoom. (50/17 = 2.94)
However a 70mm (Wide) - 200mm (Tele) lens would also be a roughly 3x zoom. (200/70 = 2.86)
Summary:
1. Optical zoom uses lenses to zoom in on the image before the sensor captures it.
2. Digital zoom uses the processor to magnify the image after the sensor captures it.
3. Optical zoom preserves the crispness and detail of the image while digital zoom tends to interpolate a lot of the data.
4. Cameras with optical zoom are generally more expensive and bigger than cameras that only have digital zoom.
5. Constant adjusting of the zoom level in a camera with optical zoom might drain the battery a little bit faster.