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This is the most I have recorded at once, and my 90 min video came out to 2.6gb and it used 52% of the battery.

so doing the math:

2.5g - 90 min
5g - 180 min
10g - 360 min

screenshot20101107at757.png
 
Yup, the limit would be your battery and not memory. Three hours of video would kill the battery. :cool:
 
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