The Kodak Zi8 and similar cameras are classified as Camcorders.
You are likely to get more responses on the Camcorders Forum.
Here is a link to the Camcorders Forum:
http://forums.cnet.com/camcorders-forum/
I need a light weight video camera similar to a Zi8 or possibly a bit larger (but small enough to be carried in a backpack). For better audio it should have capablility of using an external microphone. It should produce<span id="INSERTION_MARKER"> decent quality videos. Since it will be used outdoors where the battery cannot be recharged, the ability to replace an exhausted battery with a freshly charged battery is important. Costing more than the price of a Zi8 is not a problem.

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