Diff b/w optical zoom and digital zoom ?

Optical zoom is achieved by changing the focal length of the lens, thereby changing the magnification of the image. That way it retains all the data and image quality available when you press the shutter button. It also compresses the image: that is, it makes distant objects look closer together than they really are. Digital zoom is achieved by adding pixels to the central part of the image; pixels that were not there in the original; they are estimates of what would probably be there, based on adjoining pixels, as calculated by the camera's software. It is the same idea as cropping and enlarging in the computer with a couple of important differences: first, your computer has a lot more power and runs more sophisticated software than your camera; and secondly, you get to keep the original if you are not satisfied with the result. Use digital zoom and all you can take home is the degraded image. So, if you need to zoom in more than your lens allows, DON'T! Download the best quality image you can, and post-process it instead.

Optical zoom, the lens itself is moving to zoom in or out. This zoom gives you a full quality picture. Digital zoom on the other hand, digital zoom does some cropping on the picture. You're getting a digitally altered picture and because of this alteration, the picture loses quality.

Digital zoom is a marketing ploy to make the camera seem more powerful. My advice is to forget digital zoom, you get better results by using optical zoom and cropping the photo in post production and enlarging it.

Digital zoom isn't actually a zoom. All digital zoom does is crop the image in tighter. You're not actually getting any closer to your subject. It just looks like you are closer because it's a tighter crop. With optical zoom, your lens is actually focusing further away so you're getting closer to your subject. Optical zoom is a much higher quality than digital zoom. With digital zoom, you usually get a poor quality image that is very pixelized.

Optical zoom is achieved by changing the focal length of the lens. It retains the quality of the image delivered to the sensor while changing the magnification of the image and compressing the image: that is, it makes distant objects look closer together than they really are. Digital zoom is achieved by adding pixels to the central part of the image; pixels that were never there in the original, so are really estimates of what would have been there provided by the software. It is the same idea as cropping and enlarging in the computer with a couple of important differences: first, your computer has a lot more power and runs more sophisticate software than your camera; and secondly, if you get to keep the original if you are not satisfied with the result. Use digital zoom and all you have can take home is the degraded image. So, if you need to zoom in more than your optical zoom allows, don't! Download the best quality image and work on it in after.