View Full Version : DVHS as a Backup Drive?


Stephen Finton
August 19th, 2005, 09:17 PM
Is this possible? They're so affordable and I believe they use the same compression scheme as HDV, 25Mbps.

Ben Hardy
August 20th, 2005, 08:31 AM
Stephen,
I have 3 JVC 30ks that I bought last year, intending to use it for this very purpose. The JVCs will pass through the video from the Sony cams (for monitoring) but will not record without severe glitches. The JVC uses 19Mbps.
For archiving HDV to D-VHS, use Vegas 6 or Premiere to convert the file to HD.

If there's an easier way, I'm all ears.

How about it, anyone?


Ben Hardy

Gabor Lacza
August 21st, 2005, 07:26 AM
I recorded 3x6 minutes videos without any glitches successfully to the Mitsubishi HD20000U and played it back beautifully with the JVC HD40K.

Stephen Finton
August 22nd, 2005, 06:58 AM
I was wondering why JVC bothered to make a miniDV/HDV portable drive for $1500, when you can get a DVHS deck for $300.

Kaku Ito
August 26th, 2005, 03:13 AM
I had converted edited HDV footage to D-VHS via Lumiere HD. It worked well, but for the back up purpose, I would just use the native format, HDV.
However, I think 1080i compatible D-VHS is great for distribution. Tape is cheap, you can record over and the deck is relatively cheap. Small size digital cinema type of facility could be built around that.

Douglas Boyd
October 4th, 2005, 06:02 PM
I recorded 3x6 minutes videos without any glitches successfully to the Mitsubishi HD20000U and played it back beautifully with the JVC HD40K.

Gabor,

Based on your message, I purchased a Misubishi HD2000U and tried this. It simply doesn't work for me. The VCR does not recognize the iLink connection to the Sony HC1. Further, after reading the manual, I discovered that the manual clearly says that this unit will not connect to a camera by iLink.

So my question is: How did you do it????

==Doug

K. Forman
October 4th, 2005, 06:09 PM
Does the DVHS have S-vid or componant inputs? If the firewire (or iLink, for you Mac enthusiasts ;) doesn't work, try to record through the other inputs.

Gabor Lacza
October 5th, 2005, 04:26 PM
Douglas,
I hope I didnt confused you, but what i meant is that I recorded with the Mitsubishi deck from the computer. I used the following method.
I capture the hdv footage from the Z1 to the computer.Than
> I used Mainconcept Mpeg PRO. I export the timeline with the following
> steps:
> - File - Export - Mainconcept Mpeg PRO
> - Mpeg Stream - Advanced - Edit
> - Format Type : DVHS
> - Format Sub Type : NTSC HDTV 1080i.
> - Export.
>
> After this I wrote the files to tape with DVHS Tool.
> Any questions let me know
> Gabor

Douglas Boyd
October 6th, 2005, 08:19 AM
Gabor,
Thanks for this additional information. I was about to send my 2000U back to eBay. But now I see it can connect to a WinXP computer. Actually, I found that Vegas 6 has a tool called "Print to HDV Tape". This transcodes the timeline to720p30 and sends it to the JVC or Mitsubishi recorder. The rendering takes about 2.5minutes for each 1 minute of timeline on my P4-3.2mHz Vaio. The video looks great. I also found the options in the Cineform menus for renderign 1080i with the DVHS option, but have not yet been able to get CapDVHS to write to the 2000U. Some questions:

1. Do I need a special Misubishi 2000u driver for WinXP to get CapDVHS to work? I can capture with CapDVHS, but when I try to use the WrtDVHS function, nothing happens.

2. Why don't you write directly to your JVC40000u recorder? What benefit do you get with the 2000u? Is it that 2000u can record DVHS1080i to tape and JVC cannot?

==Doug

Gabor Lacza
October 6th, 2005, 04:38 PM
HI Douglas,
1. I didnt needed any additional driver.The original xp drivers worked vey well.
Did you checked the tape protection?? May be that is why you cannot write to it.
2. I dont get any benefit of writing to the Mitsubishi but this recorder is in my studio and the JVC40K is in my home theatre so I dont have to bring them back and forth just work with both easily.
Gabor

Douglas Boyd
October 7th, 2005, 06:45 PM
Thanks Gabor!

I already have 2 each JVC ADVHX 40Ku recorders, one for my lab and one in the media room. Actually, it was sort of a pain using the Mitsubishi due to lack of component output. So I will put the test Mitsubishi unit back to ebay.

I'm still not fully convinced that archinving to DVHS makes sense anyway because it takes so long to transcode and write tapes. An alternative which is MUCH faster is simply to copy the m2t files on to double layer dvd disks. Since each disk has about 8 gigs, you can backup a 13-gig, 1-hour MiniDV tape from the HC1 camera to two DVDs. Here's how the times compare:

Archiving a 1-hour MiniDV HDV tape:

1. DVHS: copy to computer 1 hour
transcode to DVHS 3 hours
copy to DVHS deck 1 hour
-----------
TOTAL 5 hours

2. Double-Layer DVD 4X:
copy to computer 1 hour
transcode not needed
copy to DVD drive, 1.6 disks ~1 hour
------------
TOTAL ~2 hours

Since the costs are about the same, I think the speed and image quality favor the DL-DVD solution. Further, the DVD can be played in any desktop or laptop computer using vlc.exe, but the DVHS is restricted to DVHS recorders.

==Doug

Steve Crisdale
October 7th, 2005, 07:53 PM
Thanks Gabor!

I already have 2 each JVC ADVHX 40Ku recorders, one for my lab and one in the media room. Actually, it was sort of a pain using the Mitsubishi due to lack of component output. So I will put the test Mitsubishi unit back to ebay.

I'm still not fully convinced that archinving to DVHS makes sense anyway because it takes so long to transcode and write tapes. An alternative which is MUCH faster is simply to copy the m2t files on to double layer dvd disks. Since each disk has about 8 gigs, you can backup a 13-gig, 1-hour MiniDV tape from the HC1 camera to two DVDs. Here's how the times compare:

Archiving a 1-hour MiniDV HDV tape:

1. DVHS: copy to computer 1 hour
transcode to DVHS 3 hours
copy to DVHS deck 1 hour
-----------
TOTAL 5 hours

2. Double-Layer DVD 4X:
copy to computer 1 hour
transcode not needed
copy to DVD drive, 1.6 disks ~1 hour
------------
TOTAL ~2 hours

Since the costs are about the same, I think the speed and image quality favor the DL-DVD solution. Further, the DVD can be played in any desktop or laptop computer using vlc.exe, but the DVHS is restricted to DVHS recorders.

==Doug


And there-in lies the beauty of a properly working HD Network Media Player, for those of us who felt any tape drive based back-up system had fundamental flaws.

You can of course go back to the camera with full 1080i m2t edited material, via CapDVHS or Cineform's HDLink utility, but that involves using another tape specifically for archiving - double the tape quantities at purchase time just to account for archiving. Then there's the issues of organising your instantly expanded tape collection - originals from archive, etc, etc... All very messy!!

Besides; it's a posterior pain to edit a whole stack of stuff that you want to preview at full rez, write it back to tape - and you know that it's likely to be written over when the final full version is completed. time consuming replication... Bah!!

A HD Network Media Player (preferably one with a DVD drive in it...) gets around this by allowing authoring of HD material - often WMV9, to be archived; while 'rushes' style edits can be viewed across the 10/100 wired network interface. So much more flexible than a tape only archiving solution.

Mind you - it's been an absolute disaster for PAL HD camcorder owners on the HD Network Media Player front!! All those folks who reckon there's no difference between HD PAL and HD NTSC because it's all either 720 or 1080, should have spent some time buying a HD network Media Player for their PAL HD content to play on... That would have wiped the smile of smugness off their chops!!

Any how - The point is, there's many new solutions about to hit the market (this holiday season in fact), that'll give far more effective solutions for archiving, while providing a solution for the distribution of HD level finished content to other consumers - and Hey!, you'll even get to play amazing games on some of them as well!! I'm keeping my fingers crossed that the X-Box 360 delivers for PAL HD, but the PS3 may also do the business.

Interesting times for HD ahead...

Andrew Lock
October 7th, 2005, 11:30 PM
So it seems you can't connect a Sony HDV camera to the JVC DH30000U, but has anyone had any success sending 1080i from their computer directly to the JVC DH300000U deck?

Douglas Boyd
October 8th, 2005, 11:31 AM
So it seems you can't connect a Sony HDV camera to the JVC DH30000U, but has anyone had any success sending 1080i from their computer directly to the JVC DH300000U deck?

Andrew,

That was the whole point of the discussion of this thread. The DVHS recorders cannot record the 1080i.ts streams produced by the Sony HDV cameras including HC1. These recorders, including JVC DH30000u can however record 1080i.ts streams that are re-compressed at a lower bit-rate than used in the Sony cameras. The Sony cameras compressing to approx. 25mb/s and the DVHS decks can only record up to 20mb/s. However the JVC recorder can convert 25mb/s to component output--but it can't record it to tape. The CineForm mpeg encoder that comes with both Vegas 6 and with Premier Pro has options to output mpeg.ts using a DVHS template. The settings in that template are 13mb/s for the video stream.

==Doug

Andrew Lock
October 8th, 2005, 03:39 PM
Thank you, but could someone outline the recommended process to record an HDV project from the Premiere Pro timeline using the cineform plugin, out to the JVC DH30000 deck. Is the file rendered first or can Premiere output directly to the deck?

Kyle Edwards
October 9th, 2005, 01:18 AM
But do you really want to re-encode your footage for backup purposes?

Split the original TS files into 4gig chunks and burn to DVDs has been my choice.

Douglas Boyd
October 9th, 2005, 01:47 PM
Andrew,

Gabor gave this procedure for writing to a DVHS deck a few messages back in this thread. I believe the procedure is for Premier Pro:
Douglas,
I hope I didnt confused you, but what i meant is that I recorded with the Mitsubishi deck from the computer. I used the following method.
I capture the hdv footage from the Z1 to the computer.Than
> I used Mainconcept Mpeg PRO. I export the timeline with the following
> steps:
> - File - Export - Mainconcept Mpeg PRO
> - Mpeg Stream - Advanced - Edit
> - Format Type : DVHS
> - Format Sub Type : NTSC HDTV 1080i.
> - Export.
>
> After this I wrote the files to tape with DVHS Tool.
> Any questions let me know
> Gabor

Please note that he is using DVHS Tool to write the re-compressed (transcoded) file to the deck. You can find this free software with a google search.

If you have Vegas 6, you can use tools/print from timeline HDV to write directly to the deck. But Premier Pro apparently doesn't offer that feature.

Note that Gabor's procedure preserves the 1080i format but recompresses at a lower bit rate to match the capabiility of the DVHS deck. That will result in a theoretical loss of image quality, although it looked good to me.

==Doug

Stephen Finton
October 12th, 2005, 10:29 PM
"While typical HDTV broadcasts use data rates of about 25 Mbps, D-VHS can record up to 28.2 Mbps. That’s more than sufficient to ensure every bit of detail is recorded. All Digital Television (DTV) formats can be recorded with its original Dolby Digital audio track, for up to 5.1-channel of surround sound. D-VHS encodes Dolby Digital at a data rate of 576 Kbps versus DVD’s 384 Kbps and 448 Kbps data rates. This can mean higher fidelity sound, since less compression is used for the D-VHS Dolby Digital soundtrack."

http://timefordvd.com/tutorial/D-VHSOverview.shtml

And you could store a Dolby Digital 5.1 final audio encode along with a higher bitrate final video project!

If you output back to HDV, you have to put 2-channel MPEG2 audio back onto MiniDV. With DVHS you get superior sound.

They're also 4 hours long in HS(28.2Mbps) mode.

I'm getting one or two!