Digital and optical zoom

Question

what is the difference, and what does each really mean. 'digital' just the type of zoom on a regular digital camera that does not involve a removable or adjustable lens....it's just a zoom button? and the optical is the actual removable piece?

Answer 1

First of all, optical zoom uses the lens to zoom, and yes this includes pocket size digicams (they may not have removable lenses, but most of them still have lenses that can zoom in the same way that a camera with a removable lens can zoom). This is the preferable method of zooming in terms of quality.

Digital zoom takes a small portion of the image from the centre of the sensor and makes it larger - generally this renders a very bad quality image, and can be done better on a computer if this is what you desire (mostly due to complexity of image resizing algorithms and computing power). It is exactly the same as taking the picture without digital zoom, importing it on to your computer, and taking a section out of the image to increase in size.

Answer 2

Optical zoom is the actual zooming done by the lens.  Digital zoom is a hack that "fakes" zooming, and gives you a poor quality, low resolution "zoom" by cropping the picture.

Digital Zoom is a waste of time, that only generally remains as a marketing ploy to make a camera seem more powerful than it actually is.

Answer 3

The optical zoom is achieved by aligning the physical lenses to make the subject appear larger.

The digital zoom is a special processor in the camera that interpolates the image in order to make the subject appear larger. Interploating is achieved by adding pixels that closely resemble, but not necessarily match, other pixels in the image to enlarge the image.

Digital zoom will lose sharpness and detail of the image, while an optical zoom tends to preserve it far better. Digicams that use an interpolated sensor are basically using, for example, a 5MP sensor to create a 10MP image. When combined with digital zooming, the image quality can suffer considerably.

I would never recommend using a digital zoom or an interpolated sensor.  

Answer 4

Digital just crops down the picture, and reduces your picture's resolution.  You can easily do that in editing.  Optical zoom is the lens actually zooming, and it's the only kind of zoom you should use.

Answer 5

Optical zoom is better. Optical zoom works like a telescope, it actually allows the lens to zoom in on the picture you want to take and it doesn't take anything out of your picture.

What a digital zoom does is crop out the corners of your picture and brings what is in the center forward. This is okay but if it is overdone you will lose pixels and the picture will look blurry or "pixelated".

Most cameras have both... I would stay away from the ones with only a digital zoom...