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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.
"JVC recently announced a new HDD-based digital camcorder, with storage of 20 or 30GB that is good for over 10 hours of video."
This has already been brought up, but I thought I'd go into a little more detail: The video is too compressed. For somebody capturing a home movie, it's fine. But for actually producing something that'll need to be edited and post processed, it's not a great option. The reason for that is that the footage will be degraded when it comes in. When they go to the process of putting it back to a DV tape, or to DVD etc, they'll need to compress it again. Unfortunately, that'll make the video look crummy. Worse, they would basically lose the ability to do any form of green/blue screen compositing because the compression scheme will jaggedize the edges of the matte. As it is, it's barely possible to get a decent bluescreen shot with DV. Compressing it further will basically destroy this capability.
What would be nice is if they made an HDD camera like you described, only it holds 80 or so gigs. Then make it easy to swap out the drives. If they can get enough throughput on the drives, they could capture at higher quality and bring a bunch of hot-swappable drives along. If they need longevity, they could lower the quality and get longer recording times. Flexibility is key.
We're just on the brink of some really cool advances in this arena. I wouldn't be the least bit surprised if in the next five years a hard-drive equipped camera was the norm. I'm not exactly a visionary for predicting that, though. At this point, it's a no-brainer.
"Derp de derp."
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.
Don't become a regular here -- you will become retarded.
When contemplating using an HD instead of DV tape I'd suggest that you ponder what you're losing: a field master.
I'm a Final Cut Pro user and when I bring tape into my system the first thing I do is LOG it. Then I can select what I want to capture. The tape gets write protected, of course, properly labelled, and now I can simply save my project files. At the end of a project I can discard the captured video. It's merely a matter of popping in a few tapes should I need to recapture the project.
This saves a TON of disk space that otherwise you're going to have to hold onto - or you'll lose the footage you chose not to keep (but which might be very useful). I've had no problem over five years in retrieving old footage. Yes - you might need to keep a lot of tapes but they are small.
your milage, of course, may vary -- but I recommend you have your camera cleaned and aligned and maybe treat it a little better - respect the tools you want to giv eyou good results is always a good idea.
A good quality VHS camcorder (like an old professional model)
Since when is VHS professional?
shoudl be able to tape for quite a long time and give you a great picture.
In SP (the 'greatest' picture that VHS can produce), VHS still creates a lousy picture, and the largest preloaded tapes [for NTSC] are 180 minutes.
Maybe even beta or VHS-C or 8mm or something.
I hope you mean Betacam, not Betamax, although it is better than all the other options you have stated. Oh, and still not 2 hours of continuous...
If you go out of the digital realm, you may have better luck. And there must be special VCR type things that can take those tapes and have FireWire to take the video off for you easily.
Special VCR? How about just a DV deck or a Digital 8 deck....
My other suggestion is more decidedly low tech: 2+ camcorders. Switch one on when the other is about to run out of tape.
Or you could just connect a deck to a camera, and switch the deck on just before the camera runs out, take the tape out of the camera, then put a new tape in the camera just before the deck runs out.... I used to do this with 3/4" all the time, it works out well, as you have overlap to use for editing.
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