HDV and DVHS

farss wrote on 1/17/2005, 4:13 AM

It just occured to me today that a bit of a problem with HDV is the maximum tape length is currently 62 mins which is a bit limiting for some. Now SPOT mentions in his book PTT to DVHS. Now DVHS is pretty well non existant down here but if it'll fill the bill we'll buy some decks by fair means or foul.

However we're not so certain about just what that gives us, I seem to recall someone elsewhere saying a DVHS deck will record 1080 HDV in native format. Today I heard a counter claim that the DVHS decks restream / re-encode the data. This doesn't sound quite right as I thought the clever thing about DVHS was it simply made a bit copy of the data it was fed.

If anyone's able to provide more info it'd be good to know, we're buying 4 HDV decks but maybe we'd be better off with some DVHS decks?

Bob.

Comments

JJKizak wrote on 1/17/2005, 5:27 AM

I have the JVC D-VHS deck and it records and plays back just fine. The quality is outstanding (Video and audio). I can use the Connect HD codec to record or the MY-HD 120 card in the computer. JCV also makes an HDV-Mini-DV deck ($2000.00) that is recognized by the above mentioned items. The D-VHS deck also has firewire and an NTSC analog tuner but no HD tuner.

JJK

jkrepner wrote on 1/17/2005, 6:56 AM

I'd also have to imagine that at some point there would be a full size HDV format. Just like Mini-DV and full size DV or DVCam. But who knows?

Spot|DSE wrote on 1/17/2005, 8:10 AM

I kinda doubt we'll see full size HDV decks, maybe, but doubtful. Part of the value of HDV is it allows manufacturers to use current transport assemblies, housings, etc. The only thing really different in the cam/deck side is the encoder board, and even the HD10U doesn't have that, it's playback only.
As long as you keep the bitrate below about 35Mbps, the DVHS stuff takes the print fine, and won't reencode. And I believe on some decks, it won't even reencode after that, it just blows the image/data apart.

GaryKleiner wrote on 1/17/2005, 8:43 AM

> I kinda doubt we'll see full size HDV decks...Part of the value of HDV is it allows manufacturers to use current transport assemblies, housings, etc.<

Spot, I am not following you. There are plenty of full-size DV decks out there.

Gary

farss wrote on 1/17/2005, 12:57 PM

So just to make I've got this 100% right, before we blow the budget.

I can connect a DVHS deck to my system via 1394, PTT a HDV m2t file and capture it back as exactly the same thing, just as I would with DV25, totally lossless ?

I cannot see any reason why Sony couldn't easily build a large format DV HDV deck, the existing DSR-11 transport would seem ideal. I can't even see any technical reason why they couldn't even write HDV using the DVCAM write speed and track width for added integrity.

Bob.

Spot|DSE wrote on 1/17/2005, 1:32 PM

Sorry, I read Farss post and thinking he was referring to another format/tape shell.
Yeah, we'll see DVCam size HDV decks/cams in the very near future. I don't know if Sony is going to be offering anything, but others are likely to be, based on previous announcements.

GaryKleiner wrote on 1/17/2005, 2:06 PM

Bob,

I have a JVC DVHS deck and can record fine via firewire. I have yet to figure out how to get 1394 OUT to the computer, though. Anyone know any tricks?

Gary

JJKizak wrote on 1/17/2005, 2:50 PM

I believe (not sure) that Cineform connect HD will capture from the tape as long as the tape is 720p and not copyrighted. Its been a while since I messed with it. If you code up something with the Connect HD from V5 with the stream settings they say then PTT then it will capture that no problem. I do not think it will capture 1080I from the D-VHS tape. They (Cineform) are a bit foggy on that. That was with their first generation software. What it does is actually capture anything you throw at it but it will only convert 720p to avi. With the new upgrade I don't know. I have rendered out stills in v5 with sound and changed the file ending from mpg to m2t then PTT no problem, but it was at the 720p V5 settings.
(as stated by Cineform instructions) It will then recapture and convert to avi no problem. Only via firewire. The back component jacks are only 480p. The MY-HD 120 card will capture anything you throw at it.

JJK

scdragracing wrote on 1/17/2005, 3:17 PM

bob, you should probably check out some of the hdtv stuff... avsforum.com is the granddaddy of 'em all, and i think the dvhs stuff is covered in this forum:

http://www.avsforum.com/avs-vb/forumdisplay.php?s=7d6aca98f2ff3e2e00c902858e7a2584&forumid=42

Spot|DSE wrote on 1/17/2005, 4:10 PM

You can use either Cineform or CapDVHS. There is a link to the CAPDVHS on the VASST HDV portal, as it's available both in English and Japanese. harder to find the english version, but it works pretty good. It also sees the 10U from Sony, which is a surprise.