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5GB is only ~39 minutes of DV, but would be considerably more in an MPEG-2 camcorder. One more generation though and it could well store >1 hour of video, about what a DV tape does using SP.
With that out of the way the only other consideration would be cost, and I doubt that one of those minidrives could be had for $8 USD as a 60 minute DV tape can.
Dr. Mordrid
Dr. Mordrid ---------------------------- An elephant is a mouse built to government specifications.
I carry a gun because I can't throw a rock 1,250 fps
Assuming size and price come down, having a one for one replacement (hard drive for tape) would have an advantage:
random access to the movie clips,
possibility of a reader built on the computer, rather than a deck to disk capture.
This would eliminate the one thing that at first surprised me about the DV standard: it still uses a serial access method and requires a streaming capture to the HD. When I realized you could still get dropped frames (i.e. there was no way to detect and then "fill in" the dropped frames) when capturing DV I was a bit perplexed. I would have thought that would be the first thing chaned when converting to a digital storage format.
Originally posted by jeff b Dropped frames with DV? I haven't seen that on any of my systems... and I've got one system here that really asks for trouble:
PIII-1gig on a gigabyte VIA
512k RAM
WinME or Win2kPro
Siig IEEE-1394
Sony TRV-900
MSP6.5
Turtle Beach sound card
Modem
Ultra-66 IDE
Voodoo 3dfx vid
Jeff B
I'll ask this: what drive are you capturing to?
If it is anything 7000RPM or a 5400RPM of the more recent vintages, you won't likely see dropped frames.
If you are capturing to a legacy drive, where the 5 or so MB/s that the DV standard requires, you would see dropped frames.
Never seen a dropped frame on DV, except when converting from really atrocious analogue. Surely, that was because the converter hiccupped, not because the drive couldn't cope. I have a RAID array with 2 x 60 Gb, a 30 Gb UDMA and a prehistoric 10 Gb DMA drive on my video computer. I can capture DV to the last one without dropped frames. In the days of using a Marvel, only the RAID array was drop-free, although the 30 Gb disk was 99% OK, averaging perhaps 1 drop every 5 minutes or so on a reformatted partition. The 10 Gb averaged 1 drop every second, I think!
Getting back to the original subject. I'm not a great believer in disk drives in a camera. I don't believe that a disk can stand the movements implied, especially as it isn't a hard disk, but on a Mylar substrate. Prestressed Mylar is one of the more stable polyester polymers, but it has a higher coefficient of thermal expansion than metals. Worse, the X-axis and Y-axis expansions are different so that, if it became hot (or cold), it would tend to become oval, rather than round. I've used a lot of large thick (0.18 and 0.25 mm) Mylar based process films for precision chemical milling and, even in a closely air-conned environment, stability was a problem with large, critical, parts. In some cases, we had to resort to 5 mm thick optical glass plates (guess how much they cost? - and woe betide he who broke one!). If you pack 5 Gb on a disk going into a credit card, you are well into the sub-micrometre range of precision. I can hardly believe that this would be viably reliable under the conditions that a camcorder is used under.
I have not mentioned the hygroscopicity of mylar, as I assume the unit will be hermetically sealed with a dry, inert gas filling. If there were the slightest leak allowing humid air to enter during temperature cycling, then you would be in VERY DEEP trouble
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