The difference between HDV and DV tapes
I don't know whether anybody's posted this, but this is the best explanation I've read explaining the difference between the two types of tapes:
In accordance with HDV camcorder standards, the HDR-HC1 records to MiniDV tapes. There are major benefits here: the tapes are cheap, they’re readily available, and they are compact. However, we’re scoring HDV down half a point for media over regular DV because of the importance of using high grade tapes with HDV. All tape formats suffer from a problem called dropouts, when a frame isn’t recorded because a scratch or other defect with the tape. With MiniDV and many other formats, dropouts are not a huge problem, because one lost frame when you’re working with 30 frames a second will not be noticed by the human eye.
The HDR-HC1 and all HDV formats use something called key frame compression. This means that every half second the camcorder takes a key frame, somewhat like a reference frame. The next 14 frames after that frame are based on how the video changes from that original frame. With DV, every single one of the 30 frames is a keyframe and holds all the information. Theoretically, this means that with HDV if you loose a frame because of a dropout, you’re going to loose a half second of video, it will just display as black. However, the problem is not a serious as the theory suggests - not many have reported it or lost critical footage. The higher grade "made-for-HDV" tapes do reduce dropouts, when one occurs the camcorder's LCD and VF will freeze (blank out) for half a second but the FIREWIRE HDV output contains quite a bit of useful frames and often just 3 or 4 (out of the 15 GOP) are damaged. This is a small glitch compared to what people first feared would happen on a tape dropout. Another way around this is to capture the HDV output over FireWire or component directly to a laptop or external hard disk. DVRack is about to release their HDV upgrade and other manufactures of "Pyro Firestore" type portable HDDs that accept DV are being upgraded to work with HDV feeds.
However, if you use a higher grade tape it will significantly reduce the number of or possibility of a dropout. Sony has even made a special MiniDV tape that is specifically designed for HDV shooting. Of course, this tape doesn’t come cheap, it costs $13 per tape vs. about $6 per tape for standard MiniDV tapes. But if you are shooting something important it is really important that you use the high grade tape to minimize the chance of a dropout.
Like everyone else, I've been using DV tapes with no problems whatsoever and no dropout whatsoever.
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