There is a time and/or file size limit on video recording. You probably are just hitting that limit, so the camera stops recording.
I think that limit is to prevent the imaging sensor from overheating. But I don't shoot video with my DSLRs, so am not certain of this.
Check your particular camera manual. There may be some difference in file size/time limit, depending upon caeram model.
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Alan Myers
San Jose, Calif., USA
"Walk softly and carry a big lens."
GEAR: 5DII, 7D(x2), 50D(x3), some other cameras, various lenses & accessories
FLICKR & EXPOSUREMANAGER
