DV storage options

Sat Jan 22 09:17:56 UTC 2005

Hi Justin,

I am not sure myself about the STR's you mention but I do know that the
ideal limits for firewires run at 400Mb/s and 800Mb/s.  If you are
running at 50Mb/s that seems a bit too slow.  Most Macs, I think, have
a 400Mb/s run standard.  So something is amiss and I am not sure what
to tell you (except turn off your auto screensaver and other autorun
internal devices while capturing clips).  You can also upgrade your PCI
(peripheral component interconnect).  You may want to look at:

Allegro
http://www.sonnettech.com/product/allegro800.html

You can also browse the (utterly abstract) developers notes on Mac
firewires:
http://developer.apple.com/devicedrivers/firewire/index.html

Later,

Phil Cash Cash

On Jan 19, 2005, at 7:19 PM, Justin Spence wrote:

> Hi Phil,
>
> Thanks so much for your comments!  I'll play around with FC Pro some
> more
> and try to muster the patience to actually read the you-know-what
> manual;
> the possibility of scratch-resistant DVDs is appealing as well.
>
> I took a look at the external RAID drive you pointed out on the
> videoguys
> website.  Is it correct that there's no speed advantage in using
> internal
> vs. external firewire drives for video capture and playback? I'd been
> assuming that there would be (since our older firewire connection is
> limited
> to max. transfer rate of 50Mbytes/second), but after some research it
> seems
> that most hard drives' sustained transfer rate (STR) is generally less
> than
> 40Mbytes/second, that is, less than the STR of the firewire (and the
> total
> STR is equal to the STR of the slowest part of the connection). cf.
> http://www.zipzoomfly.com/jsp/Buyers_Guide/HardDrives.jsp
> http://www.glyphtech.com/site/technology_firewire.html
>
> Also, I'm trying to get a handle on where exactly STR logjams can
> occur in
> transferring footage to and from DV cassette.  The camera is connected
> to
> the firewire, which is connected to the firewire port in the back of
> the
> computer, which is connected to the motherboard; on the other end, the
> hard
> drive is connected to the motherboard.  Are there any other relevant
> connections in this data transfer chain? Does the quality of one's
> video/graphics card matter for capture, or only for playback?  (There
> is
> output on the monitor when doing video capture, but is the incoming
> data
> stream from the firewire routed through the video card on its way to
> the
> hard drive, or is the video card getting a separate stream?
>
> Finally, although there might not be a speed advantage in using
> internal
> hard drives, this option might turn out to be cheaper.  The G4 has
> bays for
> up to four hard drives (including the boot drive) and OS X has a
> built-in
> software RAID configuration tool.  But I've gathered that
> software-based
> RAID is less than optimal since it saps processor cycles and can lead
> to
> problems if the boot drive fails (see
> http://www.uni-mainz.de/~neuffer/scsi/what_is_raid.html).  Do you (or
> does
> anyone else) have experience with the Mac RAID software?  Or any
> recommendations for a (Mac-compatible) ATA RAID controller for 2 or 3
> disks?
>
> I hope these questions aren't too tedious for everyone on the list...
>
> Justin
>
>> From: phil cash cash <cashcash at EMAIL.ARIZONA.EDU>
>> Reply-To: Indigenous Languages and Technology
>> <ILAT at LISTSERV.ARIZONA.EDU>
>> Date: Wed, 19 Jan 2005 12:25:19 -0700
>> To: ILAT at LISTSERV.ARIZONA.EDU
>> Subject: Re: [ILAT] DV storage options
>>
>> Hi Justin,
>>
>> I can provide a few comments on a DV videotape archive.  The word from
>> the LAFCPUG (Los Angeles Final Cut Pro user Group
>> http://www.lafcpug.org/tutorials.html ) is that quality brand DVC tape
>> is good for at least 20 years.
>>
>> In FCP 3, I believe it is possible to transfer directly to DV
>> videotape
>> (check the the user manual Vol. 1 page 322) but I am not sure what the
>> actual steps are for doing so.  The international settings are the
>> DV-PAL codec which is 25 frames-per-sec, which is appropriate in your
>> case, as opposed the US standard which is the DV-NTSC codec at 29.97
>> frames-per-sec.  The recent versions of FCP HD also have the DVPRO HD
>> codec which takes advantage of the latest HD technology.  But for now,
>> the DV-PAL and DV-NTSC codecs are the most widely used transfer
>> formats.  The word in the EMELD school (http://emeld.org/ ), and I may
>> wrong on this, is that MPEG-4 compression is the desirable standard
>> for
>> archving digital video whereas industry standards usually follow a
>> MPEG-2 compression standard (DVD quality).  The Sorensen standard
>> rivals the MPEG-4 standard so you have several options.
>>
>> Ideally, transfering film clips digital-to-digital should result in
>> virtually no loss in information.  However, the manner in which this
>> is
>> done can take several avenues.  A minimal set-up would be a single
>> camera and a Mac G4 with FCP (and an analog VHS recorder).  The limits
>> of your archive would be the limits of your hard drive storage and
>> with
>> standard Mac G4s this is not a lot of storage!  In any film project
>> the
>> maxim is - storage is everything and you can never get enough of it.
>>
>> So you have four options.  The first is to continue with what you are
>> doing (which may not really be an option).  The second is to buy
>> storage.  This may not be so bad as storage is getting better and
>> cheaper.  But for archiving film clips you will want a particular kind
>> of storage that is suitable to film projects (meaning you want to be
>> able to playback your film clips at suitable editing speeds).  Take a
>> look at the recent RAID technology
>> (http://www.videoguys.com/gtech.html
>> ) as this may be a nice afforable option for storage, one that I am
>> seriously considering.  The third option will be to purchase a digital
>> video tape deck (like the Sony GV-D800).  These little tape decks are
>> handy for a number of reasons, the first of which is you are able to
>> transfer digit-to-digital (camera to digital video tape deck) fairly
>> easy without having to go thru a desktop computer.  Once you create a
>> copy you can use the copy for playback onto a tv or Mac.  Finally, an
>> added (fairly new) option is transferring your film to DVD.  Of
>> course,
>> for your Mac G4, you will have to have DVD Studio Pro (a bit of a high
>> learning curve but am not sure about the most recent version).  The
>> newest DVD discs are now being made with scratch resistant surfaces
>> and
>> some are able to double their storage capacity (Blue Ray technology is
>> one of the buzz words I think).
>>
>> Anyway, these are just a few suggestions based on my limited
>> experience
>> in working with FCPRO and student filmmaking.
>>
>> Phil Cash Cash (cayuse/nez perce)
>> UofA
>>
>>
>>
>>> ----- Message from justin.spence at KATHLANGCENTRE.ORG.AU ---------
>>> Date: Tue, 18 Jan 2005 08:25:57 +0930
>>> From: Justin Spence <justin.spence at KATHLANGCENTRE.ORG.AU>
>>> Reply-To: Indigenous Languages and Technology
>> <ILAT at LISTSERV.ARIZONA.EDU>
>>> Subject: [ILAT] DV storage options
>>> To: ILAT at LISTSERV.ARIZONA.EDU
>>>
>>> Dear ILATers (ILATists? ILATicians?),
>>>
>>> I'm a linguist working for Diwurruwurru-jaru Aboriginal Corporation
>>> (Katherine Regional Aboriginal Language Centre) Australia's Northern
>>> Territory.  I'm new to the list and to endangered language work in
>>> general
>>> and am hoping someone out there might be able to help clarify a few
>>> issues
>>> related to digital video storage.
>>>
>>> In a nutshell, we record things on DV cassette and edit them with
>>> Final Cut
>>> Pro 3 on a Power Mac G4, but up 'til now we've been unable to keep
>>> digital
>>> master copies of our finished projects due to lack of disk space.
>>> Instead
>>> we've generally been exporting the final edit to VHS and then
>>> deleting the
>>> intermediate files from the G4 (so we're left with the raw footage on
>>> DVC
>>> and an analog master of the final edit on VHS).
>>>
>>> Since we're probably losing some quality and flexibility in the
>>> digital-to-analog conversion, we're exploring our options for keeping
>>> digital masters.  One possibility is storing them on DV cassette.
>>> I've been
>>> able to do this from iMovie, but is this possible from FC Pro?  Also,
>>> my
>>> understanding of DV technology is quite shaky here:  Is there quality
>>> lost
>>> in (a) transferring raw footage to the G4 in the first place and/or
>>> (b)
>>> transferring edited footage back to DV cassette (if this is even
>>> possible
>>> with FC Pro)?  Although both (a) and (b) are digital-to-digital
>>> transfers
>>> via firewire, this doesn't seem quite the same as just copying files
>>> since
>>> things like "frames per second" are involved.  (We import things to
>>> the G4
>>> using the "DV PAL 48 kHz" setting in FC Pro).
>>>
>>> Is DV cassette even a reasonable option for long-term storage? The
>>> other
>>> major option on the table is to buy some large-capacity hard disks,
>>> but then
>>> we have the problem of how to back everything up and who on staff
>>> will have
>>> the skills to cope with inevitable disk snafus.
>>>
>>> How have others out there tackled these issues?
>>>
>>> Thanks in advance for any insights you can offer!
>>>
>>> --
>>> Justin Spence
>>> Southwest Linguist
>>> Diwurruwurru-jaru Aboriginal Corporation
>>> (Katherine Regional Aboriginal Language Centre)
>>> PO Box 871, Katherine 0851
>>> e:  justin.spence at kathlangcentre.org.au
>>> p:  (08) 89 711 233
>>> f:  (08) 89 710 561
>>>
>>>
>>> ----- End message from justin.spence at KATHLANGCENTRE.ORG.AU -----
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