How many hours can a 30GB video camcorder hold?

A good rule of thumb to apply is 10 GB can record about 45 minutes of video; therefore, 20 GB - 1.5 hours, 40 GB - 3 hours, 80 GB - 6 hours, 120 GB - 9 hours, etc. This, however, is just an estimate. You will definitely get more or less depending on the quality of video. Low or poor quality will give you more time, but high or Excellent clarity will, of course, give you less time.