HAVE you seen wedding video clips in which the happy couple's faces are shrouded in shadow?

Or a holiday video shot at a resort, when the camcorder pans from a hotel room to the beach outside, the video footage goes from dim to bright abruptly?

Controlling the camcorder's exposure settings will reduce such inconsistencies.

Here is what you need to know.

Auto exposure is good

The automatic exposure mode lets the camcorder assess the entire scene, which results in tweaks to aperture size and shutter speed settings, to control how much light is let into the camcorder lens and for how long.

So, in a dim environment like a pub, the camera will increase the aperture size and lower the shutter speed for more light to produce clearer video footage, instead of a sea of black.

Or if you are on a sunny and sparkling Bali beach, it will reduce the exposure so that less light gets in - ensuring that the footage will not be all washed out.

The auto exposure mode works well most of the time.

However, it will struggle in situations where there is a sudden change in lighting or there are different light sources within a scene.

For example, in reading the available light - or metering - of the entire scene, it may not know that you want something specific, such as people's faces, to be properly exposed.

Manual exposure is better

Again, take the panning shot from a hotel room to the beach. The auto exposure mechanism may take a few seconds to adjust.

Solution: Set the exposure manually, such that when you do a panning shot, the exposure stays fixed.

Sometimes, you want a particular scene to be darker than what the auto exposure mode can produce, for a gritty horror movie look. Just decrease the exposure setting to reduce the amount of light going into the camcorder.

Also, when you shoot someone in front of a bright light, the camcorder may automatically compensate for the strong light, leaving the person's face in the shadow.

Solution: Activate the camcorder's Backlight function - use the backlight button or onscreen menu option - for the correct exposure of the subject's face.

Spot metering

In a room with the windows open and sunlight streaming in, it might be difficult to get perfect exposure.

Normally, auto exposure will show the room interior in bright detail, but what is outside the window is displayed as a blinding glow of light.

Unlike the human eye, the camcorder cannot expose for the ambient light in the room as well as the harsh sunlight accurately.

So if you want to expose correctly for the window, switch the camcorder's metering mode to Spot Metering if there is one. Otherwise, simply focus the camera on the window, leaving it stationary while shooting.

This ensures that the scenery outside the window will be captured clearly, although the compromise is that the room will appear dimmer.

With Spot Metering on (navigate to the onscreen menu to turn it on) and looking at the LCD screen, point the camcorder at the window. On some camcorders with LCD touchscreens, you simply point onscreen to "tell" the camera where to read the light.

The result may not be perfect, but it ensures that the important subjects in your video frame are clearly visible instead of being hidden in shadows or covered in a white-out.

Exposed

In the video shooting mode, look for the onscreen menu icon that looks like a square with the plus (+) and minus (-) signs inside. (Some camcorders display it as Manual Exposure).

Add the exposure to increase the amount of light going into the camcorder lens and reduce it to decrease the light.

Depending on your camcorder, you either press physical buttons or touchscreen icons or flick a stick controller to change the exposure.

You can also use exposure scene modes, if available, to circumvent the auto exposure. These are programmed to tackle specific tasks such as shooting fireworks or night scenery.

Billy Teo is a freelance technology writer who has been making home movies for the last decade

This story was first published in The Straits Times Digital Life.

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