Question about HDV decks "playing from" and "recording to"

[David Garvin]

I am looking for an HDV deck so I can backup and playback projects I'm editing in FCP. In my search, I found the following page here at DVInfo:
http://dvinfo.net/conf/showthread.php?t=45836

This thread (from 2005) indicates that the recordings from these two different manufacturers are not compatible. This concerns me.

Also, in looking at the Sony HVR-M15U, I found a review here:
http://digitalcontentproducer.com/ca...at/sony_hvrmu/

which says a couple things that concern me. One is:
"HDV records high-definition images in a compressed MPEG-2 stream (Sony's 1080i version records Main Profile at H-14 MPEG-2)."

This implies what the thread from 2005 states, and that is that different manufacturers are encoding HDV in different ways. That Sony is recording HDV differently than others.

The review also says: "you cannot take your DV tapes and make them HDV"
While this isn't something I was planning on doing, it makes me wonder about recording stuff into this deck. If I can't just output a project from FCP and record it onto an HDV tape, I wonder what exactly the limitations are. Does it have to be HDV footage that was captured on a Sony camera (as the thread from 2005 says)? Or can I take any HDV timeline in FCP and output it via firewire to this deck?


Again, I want to be able to use this to backup footage and to playback projects. This would include HDV-shot projects which have been edited in FCP and also projects that originated on Film and were telecined to some flavor of HD (ProRes422, DVCPro HD or whatever).

Can I take any HDV project from FCP and output it via firewire into these decks in the way I would do with DV to a DV deck? Or are there other aspects of this equation that I'm not understanding.

Thanks

[Mauritius Seeger]

HDV is a standard which is identical on all decks that support HDV. especially since HDV is actually encoded (or decoded) on your computer and not the deck when you transfer it via firewire. HDV tape decks are essentially nothing but a very slow outdated storage device with an added analogue video input and output module.

which is also why i think if you are only using this deck to backup HD video it's not worth it at all. infact, since HDV is so highly compressed (as opposed to DV) I don't think anyone seriously editing in HD is actually rendering out in HDV. I suggest you use a hard drive as a storage device, which allows you to render you project into more high quality formats.

finally, if you do decided you want to back up onto tape, why not use an HDV camcorder (which is much cheaper)?

[Chris Hurd]

Originally Posted by Mauritius Seeger

HDV is a standard which is identical on all decks that support HDV.

No, no, no. That is wrong, wrong, wrong.

There are two (or three, depending on how you count) different varieties of HDV and they are *not* compatible with each other. JVC's version of HDV is 720p and their decks are compatible *only* with other HDV products from JVC (and not Sony or Canon).

Sony HDV decks are 1080i and are incompatible with JVC's version of HDV.

Canon HDV is somewhat compatible with Sony decks, but only if it's 1080i material. Their progressive modes (known as 24F and 30F) are *not* compatible with Sony 1080i HDV decks (or JVC 720p HDV decks for that matter).

With HDV you must choose one single brand, be it Sony, JVC or Canon, and stick with it. There is no single standard for HDV and different HDV gear from different manufacturers for the most part do not play well together. Hope this helps,

[Mauritius Seeger]

Originally Posted by Chris Hurd

No, no, no. That is wrong, wrong, wrong.

There are two (or three, depending on how you count) different varieties of HDV and they are *not* compatible with each other. JVC's version of HDV is 720p and their decks are compatible *only* with other HDV products from JVC (and not Sony or Canon).

yes, sorry. it seems you are right. i made the mistake of assuming a properly implemented standard, which is clearly not the case. shame.

all the more reasons to steer well clear of decks in favour of hard drives...

[Chris Hurd]

It *should* be a properly implemented standard. I agree with you, it's a shame that this is not the case with HDV.

[Peter Ferling]

For a production studio, you would then need three decks or cams just be compatible for one format, (which really isn't).

I agree, it's best to have a file on a hard drive and ditch the tape. My guess is that production is going that way anyway.

[David Garvin]

Thanks for all the replies. Like Mauritius Seeger I found it hard to believe that it wasn't just data flying back and forth via firewire that would be encoded and decoded by my computer, but that was what I had read and now I guess it's confirmed.

The reason I'm looking for a deck is for long term storage. No matter what anybody says about hard drive longevity, the fact is that a hard drive will fail. I have tapes from 20 years ago that play just as well as they did back then. I have hard drives from 2 years ago which are completely useless and all data is lost.

As "bad" as HDV is, I think it's still pretty good, and it's cheaper to have film telecined offsite to an HDV tape then it is to a hard drive. And anything shot on HDV is already compressed to that format, so I'd be fine there as well.

Is there a whitepaper or full explanation somewhere about the three varieties of HDV and why JVC, Canon and Sony decks and tapes are incompatible?
Thanks

[Ervin Farkas]

An old and basic white paper Pinnacle found on our sponsor's (VideoGuys) website: http://www.videoguys.com/images/PDF/...DV_27Jun05.pdf

A more comprehensive one from Adobe: http://www.adobe.com/designcenter/pr...p_hdprimer.pdf