Thank you for being a valued part of the CNET community. As of December 1, 2020, the forums are in read-only format. In early 2021, CNET Forums will no longer be available. We are grateful for the participation and advice you have provided to one another over the years.

Thanks,

CNET Support

General discussion

Hard Drive Camcorders with 7.5 hours record time

Oct 25, 2005 3:41PM PDT

I visited Circuit City tonight and saw 3 JVC camcorders with internal hard drives. 2 with 30 gig and 7.5 hours of record time and 1 with 20 gb with 5 hours record time. Price ranged from $854 to $759. I've been trying to decide between tape and DVD, but this is new to me. Has anyone tried these or heard any pos or neg reviews?

Discussion is locked

- Collapse -
Here are the posts....
Nov 1, 2005 1:22AM PST

''Actually, I don't remember 'dancing around' the HDV question at all. Perhaps you can link to the post where you mentioned HDV and I 'danced around it'.''

You've been following this discussion thread (its obvious by your posts), yet the links below show that you don't actually READ what is being posted.

http://reviews.cnet.com/5208-7594-0.html?forumID=59&threadID=132776&messageID=1501088

http://reviews.cnet.com/5208-7594-0.html?forumID=59&threadID=132776&messageID=1502549

http://reviews.cnet.com/5208-7594-0.html?forumID=59&threadID=132776&messageID=1507560

I'm curious as to what you mean about ''They didn't have to develop a whole new camera to add HDV. They fitted it on top of existing cameras.''? I'm assuming you are only referring to the fact that HDV cameras also record onto miniDV tape. The bitrate of HDV is the same as DV, and thus can be stored on the same medium. I agree that this is convenient. However, the point is that if the image quality is SO poor from MPEG-2 compression, it would make no sense to use it for a high-definition standard.

Again, my only point here is that you have exaggerated the superiority of DV video and the inferiority of MPEG-2 video to unrealistic proportions. I am NOT claiming that the video quality coming from MPEG-2 sources is equal to DV sources.

- Collapse -
Chuckle. You still can't make'm drink.
Nov 1, 2005 2:38AM PST

OK, I'll concede that you mentioned HDV in prior posts, but you've got so much extraneous stuff in your posts that it's easy to miss these small references. I think I said more than once that I get to the point where you make a serious error, and don't see the need to read further. I also note that you are linking to your posts rather than mine. Again, perhaps you can show where I was 'dancing around' the subject of HDV.

I think I've explained enough to someone who obviously is not willing to learn or to admit his own ignorance. You, apparently, don't even consider it worthwhile to respond to a somewhat detailed explanation of what was wrong with your analysis. You choose instead to make additional assertions rather than provide any logic to back up your previous assertions. Unless some new subject arises, I see no need to waste any more time here.

- Collapse -
MPG2 VRS DV
Nov 1, 2005 6:23AM PST

One thing to keep in mind is that at the time of the DVD introduction MPG2 was the best format to get a movie onto
the DVD.
The quality depends on the compression ratio used to compress the video.
As I have been reading this I was editting some vacation video. MY MiniDv was captured as a DV by my software, this one clip is 15.5min long takes up 3.6gb of space, has a data rate of 3.5mb/sec. The rendered MPG2 of this clip takes up 697mb of space and has a data of 767kb/sec.
Both are 640x480. But the MPG2 doesn't look as good as the DV, but the MPG2 would look ok on an analog TV.
When you are talking about digital formats it is some times hard to compare when you don't know the comprssion ratio or codic that was used. John

- Collapse -
Are you saying that you've got DV on your hard drive?
Nov 1, 2005 8:10AM PST

If so, that's a bit surprising to me although I did indicate my uncertainty on that point. Is this a Mac?

Yes, I said earlier that mpeg-2 was picked because it allowed them to fit their material onto a DVD. It was probably the best compression at that time which met their objectives. However, given the sometimes political nature of these things, there could have been a better format which wasn't picked. I certainly am not ambitious enough to try to look for that answer.

Mpeg2 as a final output on the DVD is one thing. Mpeg2 as an input to the editing process is quite another. That is one reason HDV has some serious challenges, and probably why Canon has allowed for a far more data rich output from their HDV camera.

- Collapse -
Are you saying that you've got DV on your hard drive?
Nov 2, 2005 12:14AM PST

Keep in mind that DV is more of a protocal than a file format. This is on a PC and the program captuers to an AVI file and uses a codec to, if the AVI file was uncompessed it would be much larger.
So far I belive the only editting software that uses uncomprssed files is AVID Pro, FinialCut HD and Sony Vegas Pro.
To the best of my knoledge all DH camera fromats are compressed, BUT with GOOD compression codecs. There are now starting to work with 100mb/sec data rates. A "good" DVD decoded MPG2 stream is around 5~7bm/sec.
I have seen a demo of HD pro video for film production and it did feel as if I was looking out a window instead of looking a screen.
All of this stuff is changing so fast that it will have changed by the time I click on the Submit button. John

- Collapse -
OK. I've looked it up to clarify in my mind. My original
Nov 2, 2005 2:05PM PST

surmise was correct. DV, originally known as DVC (Digital Video Cassette), is a tape format, and would not be found on a hard drive.

Your original post sounded like you had DV on a hard drive which surprised me, but now you've clarified that to say that you actually have an AVI file. That makes sense also.

Since DV is a tape format, I'm not sure what you mean by the comment that it is a protocol. Perhaps, you are just referring to the general subject of digital video. Whatever, the answer is not really that important.

- Collapse -
And further consider this...
Oct 28, 2005 7:07AM PDT
- Collapse -
(NT) (NT) Nice link.
Oct 28, 2005 10:19AM PDT
- Collapse -
Format quality!!!
Nov 3, 2005 12:31AM PST

This link to another post is realy very similar to what we are talking about in this one.
http://reviews.cnet.com/5208-7594-0.html?forumID=59&threadID=131820&messageID=1487100
I haven't had the chance to get a hands on the JVD HD camera.
I have been looking a various editting software and what type of file, size per min of video, compresion used and data rate. I will post the results. but so far they all import to a AVI file and data rates of 1.1~3.2gbits per sec. Yes Gigabits they list it as 1,134kb date rate. So DV is the way to for quality. I think a lot of us know that, but I will put some numbers in so we will have a reference. John

- Collapse -
RE: OK, I've looked it up to clarify my mind....
Nov 3, 2005 3:46AM PST

We've hit the maximum depth of a discussion thread, so I had to post in response to the original reply.

As was mentioned by jcrobso (John), this is also being discussed in parallel in another discussion in the camcorders forum:

http://reviews.cnet.com/5208-7594-0.html?forumID=59&threadID=131820&messageID=1487100

To ease any confusion regarding DV, it is both a tape format and a video codec. As such, it can be transferred in digital form to a computer hard drive for editing. I have done this many times with digitized video from an analog camera.

From wikipedia.org (http://en.wikipedia.org/wiki/DV):

"'Digital Video (DV)' is a video format launched in 1996, and, in its smaller tape form factor MiniDV, has since become one of the standards for consumer and semiprofessional video production. The DV specification (originally known as the Blue Book, current official name IEC 61834) defines both the codec and the tape format."

- Collapse -
disk write errors?
Nov 29, 2005 2:42AM PST

So I gather that the JVC disk recorders are suitable for normal consumer use, quality is good, copying movies to DVD is simple and the camera is physically light and easy to handle. Has anyone had experience with disk write errors when recording under turbulent conditions, meaning recording when skiing, or riding a bike, or things like that? In essence, the hard disk write function has to be similar to PC disk writes, where something has to touch a wafer. Anyone seen missed video frames when the camera is shaking?