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Cheap Tapeless DV Capture?
K'thardin asks: "Recently I've been chafing under the limitations of mini-DV tapes, as I attend various conventions throughout the year and record certain events and information panels. These limitations include dropped frames, gummed up tape heads (especially prevalent when you spend more than fifteen minutes at a time on pause), and most importantly, time constraints as the largest mini-DV tapes can only hold 83 minutes on SP (a little over 2 hours on EP, with a loss in quality and larger possibility of dropped frames). Several events I attend can run for 4 hours or more, so the time constraint is one of the worst, as it requires me to change tapes several times, thus loosing vital footage." Are there video acquisition devices out there that can record to high density media as well as (or instead of) DV Tapes? If not, how difficult would it be to build a portable one?
"There are several tapeless acquisition systems out there, such as the Firestore FS-4, the QuickStream, and the ADS Pyro drive. The advantages to these solutions are generally longer recording time, elimination of dropped frames, and the ability to record natively in several video formats, removing the need for time-consuming tape capture. The problem with most of these is that they are prohibitively expensive for the larger capacities, require user-built portable power solutions for long duration recording times, are not upgradeable, and have been reported to be buggy by several users.
Considering these devices are little more than specialized computers, I've been considering what sort of devices would be a cheap and more reliable alternative to commercial offerings. An article on DVInfoNet details the creation of a relatively cheap and upgradeable tapeless acquisition system that uses a tablet PC. The problem with this is power and space constraints. There are several existing and upcoming Linux-based devices out there (as well as those that can be made to be Linux devices) that can be made to do what I wish with the capacities I need. The problem there is that none of the ones I've found come with a Firewire port, which is vital for tapeless acquisition on current DV based cameras. Also is the problem that many of these acquisition systems do not have the capability of being upgraded, or simply lack the ability for one to swap out hard drives should it become necessary (such as recording two 4-hour events back to back ... I've done this). The only possible solution I've seen containing a needed Firewire port is the Apple iPod, and it doesn't seem to have the ability to process the information coming in from a camcorder fast enough to prevent jittery video; nor is it upgradeable.
Does anyone else have this complaint? Are there any devices I've overlooked that fit the criteria of small, relatively powerful, cheap, power-efficient, Firewire-enabled devices with upgradeable/swappable hard drives that are able to run Linux?"
Considering these devices are little more than specialized computers, I've been considering what sort of devices would be a cheap and more reliable alternative to commercial offerings. An article on DVInfoNet details the creation of a relatively cheap and upgradeable tapeless acquisition system that uses a tablet PC. The problem with this is power and space constraints. There are several existing and upcoming Linux-based devices out there (as well as those that can be made to be Linux devices) that can be made to do what I wish with the capacities I need. The problem there is that none of the ones I've found come with a Firewire port, which is vital for tapeless acquisition on current DV based cameras. Also is the problem that many of these acquisition systems do not have the capability of being upgraded, or simply lack the ability for one to swap out hard drives should it become necessary (such as recording two 4-hour events back to back ... I've done this). The only possible solution I've seen containing a needed Firewire port is the Apple iPod, and it doesn't seem to have the ability to process the information coming in from a camcorder fast enough to prevent jittery video; nor is it upgradeable.
Does anyone else have this complaint? Are there any devices I've overlooked that fit the criteria of small, relatively powerful, cheap, power-efficient, Firewire-enabled devices with upgradeable/swappable hard drives that are able to run Linux?"
The HDV format used in a JVC and two new Sony prosumer cameras is also 13 GB/hour- it uses mpeg2 to achieve the same bit rate as regular DV. It looks superb in motion compared to SD, but if you freeze a frame and zoom in you can see compression artifacts- I haven't inspected broadcast HD closely, it has a similar bit rate to HDV (~20 mbps).
miniDV EP is the same quality as SP. The only difference is the tape speed. The data packets are the same.
Dropouts? I've been using miniDV for years in an industrial environment and I never have dropouts. Your camera is gummed up as you've already explained.
Always use fresh tapes for important events and record them, completely, with the lens cap on then rewind to retension and create a proper timecode on the entire tape. Don't reuse tapes, keep your camcorder clean and stick to one tape manufacturer.
Pause for 15 minutes while recording? Huh?!?! Most camcorders shut themselves off. There's no good reason to be on pause for 15 minutes. Turn it off then back on.
You don't need a HD. What you need is attention to detail and, it seems, a second camcorder and tripod. Record overlapping segments and do post-editing.
It seems like the person posting the topic doesn't really understand what they are doing - or rather, they don't have a good foundation on which to improve their problems. So instead they are looking for a product (that's not prohibitively expensive) that caters to the way they think things 'should be done'.
Welcome to Ask Slashdot.
"Hi, I'd like to do $THING. I know that $SOLUTION_A and $SOLUTION_B will do it very easily and for a very reasonable price, but I don't want to use $SOLUTION_A or $SOLUTION_B because $VAGUE_REASON and $CONTRADICTORY_REASON. Instead, I'd like your under-informed ideas on how to achieve my $POORLY_CONCEIVED_AMBITIONS using Linux, duct tape, an iPod, and hours and hours of my precious time."
With apologies to the inquirer.
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