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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?"
You just need to remember to change tapes after George Takei talkes, and before the costume contest starts.
How about... analog? Is digital a requirement? A good quality VHS camcorder (like an old professional model) shoudl be able to tape for quite a long time and give you a great picture. Maybe even beta or VHS-C or 8mm or something. 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.
My other suggestion is more decidedly low tech: 2+ camcorders. Switch one on when the other is about to run out of tape.
Comment forecast: Bits of genius surrounded by a sea of mediocrity.
JVC recently announced a new HDD-based digital camcorder, with storage of 20 or 30GB that is good for over 10 hours of video.
D =1 e s-Four-Hard-Drive-Based-Everio-Camcorders.htm
http://www.jvc.com/press/index.jsp?item=461&pageI
http://www.camcorderinfo.com/content/JVC-Introduc
Why not stop recording?
FWIW, I do video / film production for a living.. this just doesn't make sense. Consumer DV camcorders switch off automatically after a few minutes for a reason - not to save battery life *tho that's a benefit* but because of the exact 'gumming' thing mentioned. The drum spins and creates a magnetic effect which pulls tiny metallic particles off of the tape. Too much of this and your drum/heads/tape gets messed up.
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'.
Learn to work how the gear is designed to work. Then start experimenting.
I'd hate to have to sit thru your home movie collection.
This issue is a bit more complicated than you think.
might not be quite what you want, but some notebook can be set so they do not sleep when the lids are closed. i only know Mac notebook, and that is a feature of the powerbooks (but not ibooks).
you can carry the notebook in a shoulder bag and hook a DV cam to record straight to the internal drive (bypassing the tape). you would have to offload it later if you want to keep the files at full quality, but that may do it? i do know people do this. it has that 80's camcorder thing going but it may be the cheapest solution.... in the sense that the notebook is not dedicated to this project and you can use any handheld video camera with firewire output (even an apple isight).
Apple powerbooks have had this feature for a few years, and i really doubt they are the only ones. i am not saying they were first either, i just do not follow other notebooks. the only thing to ponder is that it is a software setting that tells the machine if it should sleep or not when the lid is closed. if the notebook was designed to run OS X or Windows, there may not be an easy way to control that from a Linux install.
i would assume there is some other all-in-one option, but it might be prohibitively expensive?
I am hit by this limitation sometimes too, as I frequently record services, special functions, etc., at my church, and many of them run longer than an hour or hour and a half. Lately I've just been bringing my laptop with me (PowerBook G4 12", 80G drive) and recording directly to the hard drive via iMovie. Yeah it's not Linux, but you can get an iBook with 100G hard drive for $1199 from Apple. That will hold a TON of video.
Slight correction to a common misconeption about MiniDV tape and the DV format:
There is no loss in quality going to LP recording mode compared to SP mode. It is still 25 Mb/sec.
Switching to LP you give up reliable insert editing, recording/playback compatibility with other cameras, and audio dubbing. And you are more likely to have dropouts. But aside from these things, SP and LP produce identical quality video.
And Digital-8 has the same quality as well. Same 25 MB/sec recording rate. The reason Digital 8 is perceived as an inferior format is because it appears on relatively lower quality cameras. You can dub DV digitally to a Digital 8 deck and you will end up with a perfect copy.
iSight is a fun toy, and good for confrencing and maybe seeing a girl naked on the other side of the country, I don't think it'd be that great for recording your favorite stripper's 4 hour set.
Step 2: Get a laptop with IEEE1394 and install the biggest hard disk that you can. (External hard disks could also be used here.) Use a program like DVIO to capture the incoming DV frames and dump them to a file on your hard disk.
Presto! DV video capture limited only to the size of your disk partition.
If you don't know where you are going, you will wind up somewhere else.
hehe, he means porn, hehe.
The first rule of USENET is you do not talk about USENET.
And when you use DVD instead of MiniDV your picture quality drops significantly. DV has a vastly superior picture to most MPEG-2 implementations. These cameras have to use single pass MPEG-2 encoding, at a maximum of 4-6 Mb/s. DV, though a different type of encoding that doesn't have some of the advanced motion analysis of MPEG-2, has a constant bitrate of 25 Mb/s, which is quite good. And it is better for editing with random seek and insert capability.
For the highest quality video, stay away from the DVD camcorders.
If you can afford it, DV Rack is a great software solution for direct-to-disk capture. It has some neato tools to make sure you are getting the best picture you can. It also has this cool feature that constantly buffers video, so when you hit the record button on your camera, it actually records several seconds of video prior to pressing the button. Perfect for those times when something happens real fast and it takes you a second to react.
Every DV camera I have ever used outputs video to the firewire port whenever the camera is on. I don't believe it is common to find one that doesn't.
You can always capture directly into editing software too, but it is a little more cumbersome.
DV Rack (http://www.dvrack.com/ by Serious Magic runs on a laptop and was made to do exactly this plus it has automatic quality monitoring that watches video and audio levels in real-time alerting you when thresholds are exceeded. It also turns your laptop screen into a field monitor that lets you compare live camera to recorded clips in split screen (good for checking continuity/framing).
There's an express version that lists for $149.
Disclaimer: Yes, I work at the company but hey someone finally asked a question on Slashdot that requests exactly what a product that I worked on does.
I actually have a similar issue as the root poster and found this solution myself. I hook my laptop up to my DV camers, turn it on and it stays on becuase the firewire is hooked up. Normally it turns off after 15 minutes but I tested it on Friday and captured 3 1/2 hours before the camcorder batter strted running down. This is perfect for long events. On a side note My laptop's HD is 60GB of which 40 are free (I cleared it out for this test) Just for fun, I setup Vegas' capture to use my 40GB USB drive (it's the drive that came in my laptop, only 4200RPM - in a little enclosure it's powerd off the USB) and it worked perfectly, not a dropped frame. Provided your batteried last long enough or you have a power port this should be able to go for 8 or more hours, just get more HD space. Sony Vegas (which is what I was using) can add a dozen or more drives and use them in sequence as they fill up. You can get a bunch of laptop crives and enclosures if you want to use the host battery - or 3.5" enclosures and regular 250-300GB drives if you're doing it with AC.
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.
To get less dropped frames, use DVCAM tape in your miniDV camera, not cheap miniDV tape. DVCAM has a much stronger backing, better lubrication and is generally worth the extra money.
Wooooooah there. Are you a Sony dealer? You sound like one.
For one thing, using DVCAM tapes in your non-Sony camera will cause *more* dropouts as the "better lubrication" gets mixed up with the lubricants from whatever tapes you were using before and basically creates a big mess. Notably, sticking Sony tapes in a Panasonic camera is asking for trouble.
Better advice would be: Use one brand of tapes, and never, ever, switch.
Better yet, use a Sony DVCAM camera with the DVCAM tape...
You *are* a Sony dealer!
Check out the Panasonic P2 cameras
Ok, maybe you're not a Sony dealer...
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.
Bottom line is that if you're getting clogged heads after pausing for 15 minutes, you are either using A. the cheapest, crappiest, oldest, most unbelievably shedding tape in the known universe or B. the worst camcorder ever manufactured. Figure out which of these is the case and replace the defective part in question. If you're having enough problems with DV tape to warrant this sort of complaining, there's something seriously wrong.
Don't get me wrong, I'd love to see something like an iPod repurposed using a Linux-based firmware to do DV capture. It's something somebody could probably hack together in a few hours, given that Linux already runs on the things (or at least some models thereof). However, the reason I'd like to see it is not because tapes aren't a good archival medium, but because for the purposes of video production work, it would be a tremendous time savings if you could skip the capture part entirely and just copy a file across.
Check out my sci-fi/humor trilogy at PatriotsBooks.