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Do You Need Automatic Camcorder Controls?

If you read the ads, you'll notice that manufacturers seem to feel that automatic camcorder controls are a must-have feature for most videomakers.

However, even if you're an inexperienced user, it won't take you long to discover that automatic controls and image processing features are usually more trouble than they're worth. If you're hesitant to buy an otherwise attractive camcorder because it lacks automatic controls, our advice is to go ahead and buy.

All professional camcorders give you the ability to turn automatic functions off and use manual controls instead. But it's a challenge to find low-cost or budget-level camcorders with manual overrides for automatic functions.

The Price You Pay for Image Processing

DV camcorders at all price levels offer various sets of automatic controls, including auto exposure (AE), auto-focus (AF), auto white balance (AWB), and automatic audio gain control (AGC) or automatic level control (ALC). AE and AF take the place of making manual lens adjustments, AWB compensates for variations in the color of lighting sources, and AGC is an automatic audio volume control.

Unfortunately, most automatic features sacrifice quality for the sake of convenience. No digital processing circuitry, no matter how sophisticated, can read the mind of a videographer.

For example, consider what happens in a DV camcorder when you use its "automatic electronic image stabilization" feature:

The lighter the camera, the more difficult it is to move it smoothly. Automatic electronic image stabilization compensates for camera jiggle by selecting a smaller-than-normal portion of the CCD to frame the image. If the image drifts or jiggles toward the edges of the CCD, the camcorder's processor selects the new boundaries as the correct image framing.

However, by using a smaller-than-usual portion of the CCD's active picture area, this function sacrifices resolution and steals pixels from the CCD. It delivers a picture that's less sharp than if you had turned off the feature and simply found a way to hold the camera more steadily.

Want another example? If you pan across a bright light source, AE won't be able to adjust fast enough. The circuitry will undercompensate, then overcompensate, and by that time you'll be off the bright light, and the exposure will need to auto-adjust again.

More examples:

Autofocus gets confused in action-packed scenes. It may focus on objects at the center of the frame, not on the main character who is making a hasty exit at frame right.

Auto white balance is designed to take a guess, based on the assumption that the brightest areas of a scene should be white. What if they're supposed to be hot pink?

Automatic audio gain control will crank up the audio gain as soon as the scene goes quiet. The result? You'll make a clear, digital recording of the house air-conditioning system. The opposite happens when actors shout: AGC can't crank the volume down fast enough, and audio distortion results.

Other automatic features are just as likely to get in your way. Examples include shadow enhancement or reduction, picture sharpness control, color correction (other than white or black balance), and digital transition effects (such as fades and dissolves). All of these effects are best handled in post.

Do you need automatic camcorder controls? Let's put it this way: Do you need training wheels on a bicycle?

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