does the Canon HF R series meet your requirements?
<span id="INSERTION_MARKER">I need a light weight camcorder similar to a Zi8 or possible a bit larger (but small enough to be carried in a backpack. For better audio it should have capability of using an external microphone. It should produce 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. It should be compatible with a Mac computer.

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