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To have a better understanding of your issue, please let everyone know what model camcorder you are using. That way, the community will be able to assist you with suggestions appropriate for your product.
Any other details you'd like to give will only help the Community better understand your issue!
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In the AUTO mode, the camcorder will automatically detect certain characteristics of the subject, background, lighting conditions, etc. It will then adjust various settings (focus, exposure, color, image stabilization, image quality, among others), selecting the best set-tings for the scene you want to shoot. Because of this, it is possible that any of the settings is prefereable, so long as it matches up well to what you are shooting.