Hi,

If I use a sony dcr vx9000e camera that uses DVcam tape to record something,
then edit on pc, and print to mini dv tape, is the quality reduced by going
to mini tape, rather than dvcam tape?

In general is there a difference in quality between dvcam tape and mini dv
tape?

Thanks,

Brad

"Brad Gerrard" wrote in message
...
Hi,

If I use a sony dcr vx9000e camera that uses DVcam tape to record
something,
then edit on pc, and print to mini dv tape, is the quality reduced by
going
to mini tape, rather than dvcam tape?

In general is there a difference in quality between dvcam tape and
mini dv
tape?

'In general', none at all. DVCAM has a 50% wider track width and as a
consequence runs for only 2/3 the time. It should therefore offer
greater resilience against various gremlins like tape drop out, minor
head alignment issues etc.

There is also a minor variation in the way audio is recorded which most
people aren't concerned about.

If you mean the tape stock rather than the recording format, then Sony
claim that their DVCAM tape is a step up in quality from their Premium
and Excellence ranges - so it should be given the price differential.
Much nicer boxes though.
--
Malcolm

"Malcolm Knight" wrote in message
...

'In general', none at all. DVCAM has a 50% wider track width and as a
consequence runs for only 2/3 the time.

Interesting. Time for me to get with it!

I understood that the VX9000 used "Full size" DV tape ie. the big cassettes.
I also thought that DVCAM was just miniDV tape running at an increased tape
speed with locked audio.

So you can have a full size DV tape running in "DVCAM" mode OR standard DV
mode??

Can someone confirm/enlighten me (I've never owned a camera with a full size
DV mechanism).

Regards,
Hughy.
--
I can be found at airways under_score electronics a_t bigpond d_o_t c_o_m.
If you spam me, I **guarantee** that I'll report you.

So you can have a full size DV tape running in "DVCAM" mode OR standard DV
mode??

Full size and mini cassettes for both DV & DVCam are identical, barring
claims from manufacturers that 'better' stock is put in shells labelled
DVCam. You can use either DVCam cassettes in a DV device or vice versa.

DVCam is a modest refinement of DV; both use the same DV25 codec, both use
the same 4:1:1 chroma sampling (NTSC), both the same 5:1 compression (so too
does DVCPro share all these commonalities). DVCam moves the tape through
the device at a higher speed, so a tape doesn't last as long, and the 25Mb/s
signal is 'spread' over a greater tape area. DVCam devices may also use a
wider head ... but they don't have to, as confirmed by the PD150 for
instance, which can record either DV or DVCam and uses DV standard heads.
There is a minor change in how audio is handled in DVCam devices to make
linear deck to deck editing easier -- audio frames are timed to sync with
video frames so that boundaries are always physically aligned; a cut on a
video frame will not truncate an audio frame and cause a blip. This audio
handling is not important to NLE usage, and neither is it very significant
to deck to deck editing as most capable decks perform an audio cross
dissolve automatically at a video cut point to mask any audio errors -- this
audio/video frame boundary alignment is known as 'locked' audio, and
contrary to popular wisdom has nothing to do with audio sync ... which is of
course always perfect in any tape based recording format.

So yes, you can run either large or mine cassettes in either DV or DVCam
mode, with a corresponding adjustment in the tape run time.

GB

"Hughy" wrote in message
...
"Malcolm Knight" wrote in message
...

'In general', none at all. DVCAM has a 50% wider track width and as
a
consequence runs for only 2/3 the time.

Interesting. Time for me to get with it!

I understood that the VX9000 used "Full size" DV tape ie. the big
cassettes.
I also thought that DVCAM was just miniDV tape running at an increased
tape
speed with locked audio.

So you can have a full size DV tape running in "DVCAM" mode OR
standard DV
mode??

Can someone confirm/enlighten me (I've never owned a camera with a
full size
DV mechanism).

There are two sizes of cassette. Big and small. Both may be marked
either DV or DVCAM. The golden rule is; if it will be accepted by the
tape slot it will work. You will get a DV recording or a DVCAM recording
dependent on the machine - many recent ones are switchable.

All DVCAM machines will play back SP DV as well as DV. All Sony DV units
will play back DVCAM (apart from first generation DV, VX700/VX1000) and
a few JVC devices will also play back DVCAM.

IIRC the VX9000 (and maybe the DSR200) were the only units which didn't
accept small size cassettes. All others that take a big tape will also
take small. There were also (IIRC) some sort of incompatibility with
tapes recorded on the VX9000, something to do with audio. Sony used to
put a 'qualifier' in the manuals of some of the later VCRs to cover it.
All a bit of a hazy memory now.
--
Malcolm

"Malcolm Knight" wrote in message
...

All DVCAM machines will play back SP DV as well as DV.

Ahem... 'as well as DVCAM'.

--
Malcolm

I'm interested in the difference between locked audio and not locked
audio. My understanding of an audio "frame" is that it is one sample,
which in the case of DV usually represents a timespan of 1/48000
second. If I am correct (which I suspect I am not), the worst case
scenario that could occur when using a not locked audio system is that
an audio cut could be made 1/48000 second later or earlier than a
video cut, which doesn't seem like too much to worry about. Would you
(or anyone else) be so kind as to elucidate?

"RGBaker" wrote in message . ..
There is a minor change in how audio is handled in DVCam devices to make
linear deck to deck editing easier -- audio frames are timed to sync with
video frames so that boundaries are always physically aligned; a cut on a
video frame will not truncate an audio frame and cause a blip. This audio
handling is not important to NLE usage, and neither is it very significant
to deck to deck editing as most capable decks perform an audio cross
dissolve automatically at a video cut point to mask any audio errors -- this
audio/video frame boundary alignment is known as 'locked' audio, and
contrary to popular wisdom has nothing to do with audio sync ... which is of
course always perfect in any tape based recording format.

Thanks for the explanation (here it is again in case anyone missed it!)...

"RGBaker" wrote in message ...
I'm interested in the difference between locked audio and not locked
audio. My understanding of an audio "frame" is that it is one sample,
which in the case of DV usually represents a timespan of 1/48000
second. If I am correct (which I suspect I am not), the worst case
scenario that could occur when using a not locked audio system is that
an audio cut could be made 1/48000 second later or earlier than a
video cut, which doesn't seem like too much to worry about. Would you
(or anyone else) be so kind as to elucidate?

In a linear edit it isn't later or earlier ... it is precisely where ever it
falls when you cut on a video frame. And if it is in the middle of an audio
frame, the audio frame is corrupt & becomes a blip. The trick to locked
audio is that when ever the video frame ends, so too ends an audio frame.
The number of audio samples per second doesn't change, but the audio signal
is 'padded' so that the math always works out to match the frame ends.

"RGBaker" wrote in message
...

So you can have a full size DV tape running in "DVCAM" mode OR standard
DV
mode??

Full size and mini cassettes for both DV & DVCam are identical, barring
claims from manufacturers that 'better' stock is put in shells labelled
DVCam. You can use either DVCam cassettes in a DV device or vice versa.

DVCam is a modest refinement of DV; both use the same DV25 codec, both use
the same 4:1:1 chroma sampling (NTSC), both the same 5:1 compression (so
too
does DVCPro share all these commonalities). DVCam moves the tape through
the device at a higher speed, so a tape doesn't last as long, and the
25Mb/s
signal is 'spread' over a greater tape area. DVCam devices may also use a
wider head ... but they don't have to, as confirmed by the PD150 for
instance, which can record either DV or DVCam and uses DV standard heads.
There is a minor change in how audio is handled in DVCam devices to make
linear deck to deck editing easier -- audio frames are timed to sync with
video frames so that boundaries are always physically aligned; a cut on a
video frame will not truncate an audio frame and cause a blip. This audio
handling is not important to NLE usage, and neither is it very significant
to deck to deck editing as most capable decks perform an audio cross
dissolve automatically at a video cut point to mask any audio errors --
this
audio/video frame boundary alignment is known as 'locked' audio, and
contrary to popular wisdom has nothing to do with audio sync ... which is
of
course always perfect in any tape based recording format.

So yes, you can run either large or mine cassettes in either DV or DVCam
mode, with a corresponding adjustment in the tape run time.

GB


AFAIR a DVCAM recording can only be played back in a DVCAM device, whereas a
DV recording can be played back in either (assuming the ability to take the
size of cassette!)

At work I use a DSR-200 camera (large cassettes only) and a DSR-30 vcr
(either size), edit using Premiere on a Mac - and sometimes run off a miniDV
tape to take home to watch on my GV-D300.

Bizarrely, before I can get the DSR-30 to accept a FireWire signal from the
Mac (for recording back to tape) I have to force it into Unlocked Audio mode
(which involves switching it on whilst holding down record and pause).

Hamish

AFAIR a DVCAM recording can only be played back in a DVCAM device, whereas
a
DV recording can be played back in either (assuming the ability to take
the
size of cassette!)

All Sony DV devices except the two that predate DVCam (vx1000, vx700) can
play DVCam. Some non-Sony devices too.

GB