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Optical & Digital Zoom

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Many point-and-shoot and digicam cameras have two types of zooming, optical and digital.

Optical Zoom

A zoom lens contains several lenses.

As you zoom, these lenses change position to magnify the image.

The magnification, done with lenses, is called optical zooming.

Digital Zoom

When the zoom reaches it maximum magnification (the most millimeters or mm's) your camera may switch to digital zoom.

Digital zoom uses software, no lenses.

The camera software:

• Takes the center of the image and crops it.

• The small image is enlarged by adding pixels.

The pixels are added to make up for the loss of quality.

Example

Let's say you spot some Jame's Flamingos.

You zoom in (more mm's).

You take a photograph of the threesome.

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One of them has a rare mutation—a blue neck.

You want to photograph the neck.

You zoom in more.

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Because the lenses in your zoom lens can't move any further, the camera switches from optical zoom to digital zoom.

The camera stores the image of the three flamingos.

As you zoom in, the camera crops the three-flamingos image.

When you press the shutter release, the camera adds pixels to improve the quality of the cropped image of the neck.

Quality

Digital zoom is, usually, inferior to optical zoom.

However, if it's the only way to get the photograph you want, go ahead.

Better to Crop Later, Instead?

You could forgo digital zoom.

You would crop the photograph of the three flamingos later, with Photoshop Elements.

However, the quality of camera cropping (digital zoom) is probably superior to Photoshop-Elements cropping.

That's because the camera is cropping the raw information of the image.

The raw information is what the camera processes into a JPEG file.

The amount of raw information is huge compared to that of a JPEG file.

So, it's usually better to crop and enlarge using the raw information, the digital zoom.

However, if you're saving your photographs as raw files, go ahead and crop later.

The quality may be better than what the camera does with the same raw information.