Why changing image format changes the area shown on the LCD screen ?

Question

Recording pixels option when set to Large 14M 4320x3240, in Canon PowerShot SX 210 IS, puts black bars on the vertical sides of the screen. The shot is NOT thus fully seen in its LCD screen.

Why is this happening? Is this normal?

Answer

The LCD screen on your camera is a 16:9 aspect ratio, so when you shoot in a 4:3 aspect ratio, it puts black bars in the 'extra' space.

Aspect ratio is just the ratio of the height and the width of your image. Your LCD is a 'widescreen' LCD with a fairly common ratio of 16:9, however, most digital pictures are shot at 4:3. When you change your camera to this format (4:3), the camera does its best to fit as much of the picture in your LCD without cutting anything off. What this means is that the center 2.5" of your 3" is really only used on most 'normal ' pictures, the rest shows black bars.

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