with them. AJA had some reason to put them in there, but they could not be
bothered to include why in any of their manuals.
Independent of that, I have always had terrible issues with FCP and *any*
video I/O when it comes to frame accuracy and serial control. I expected
those to go away with using same hardware with MC, and they HAVE. AJA makes
tremendous hardware, but they don't or can't control how the software will
react. Avid's implementation of serial control protocol has always been
solid, so that works. FCP's implementation lacked big time, and I think the
A vs. B presets tried (in vain) to compensate for the bigger issues with
that.
The most troubling thing with AJA is that unlike other companies, they
don't give you a nice white paper with your product. One that says: when
doing x conversion, be prepared for y offset. Not sure if they care. I did
contact them with my findings, and they said something to the effect of,
"yeah, that all seems right".
On Wed, Apr 11, 2012 at 11:13 PM, johnrobmoore <bigfish@pacbell.net> wrote:
> **
>
>
> That's an interesting chart of offsets. I did an extensive frame accuracy
> test with FCP a few years back with a Kona2 or 3 and I found the video
> accuracy required the device to be set to Sony B not Sony A preset. The
> difference rolled the timeline one frame earlier relative to the record
> machine and made it possible to do proper insert edits. In the default Sony
> A the first frame of an insert edit would be doubled up because the
> sequence timeline in FCP rolled 1 frame late. I see most of your offsets
> are showing video 1 frame late which could be a by product of being in Sony
> A device preset. Did your tests involve Sony Machines and the Sony A vs. B
> presets in FCP? My tests did not involve any audio so I didn't check for
> that. Boy you'd think embedded audio would have to stay in sync kinda like
> VITC but I too have been told by AJA that some of the problems I found they
> were aware of and blamed a lot on QT.
>
> --- In Avid-L2@yahoogroups.com, Mark Spano <cutandcover@...> wrote:
> >
> > Conversions with AJA hardware are notorious for ditching sync between
> audio
> > and video. If you can spot it, you can compensate for it in sequence.
> > Otherwise, do separate layoffs. This is with KONA, LH, iO, etc. - I do
> > not rely on these to make conversions unless there's no audio involved. I
> > did extensive testing a few years ago and posted my findings on the Cow
> and
> > sent to AJA. They confirmed all of them. I made myself a cheat-sheet for
> > them, for the KONA 3. Here it is:
> >
> > KONA 3 Output - Delay Compensation for Video Conversion
> >
> > When not performing any conversion on resolution or frame rate, the KONA
> 3
> > is frame accurate in edit to tape for video and audio.
> >
> > --
> > When upconverting (for example, 525i29.97 to 1080i29.97 - only
> resolution,
> > not changing frame rate) the output from KONA 3 is frame accurate for
> audio
> > and 1 frame late for video.
> >
> > To compensate for this, shift video in sequence earlier by one frame.
> >
> >
> > When downconverting (for example, 1080i29.97 to 525i29.97 - only
> > resolution, not changing frame rate) the output from KONA 3 is frame
> > accurate for audio and 1 frame late for video.
> >
> > To compensate for this, shift video in sequence earlier by one frame.
> > --
> >
> > --
> > When converting (1080sf23.976 to 1080i29.97 - adding pulldown only, not
> > changing resolution) the output from KONA 3 is frame accurate for both
> > video and audio.
> > --
> >
> > --
> > When crossconverting (720p59.94 to 1080i29.97) the output from KONA 3 is
> > frame accurate for video and audio is one field early in 29.97i.
> >
> > When downconverting (720p23.976 to 525i29.97) the output from KONA 3 is
> > frame accurate for video and audio is one field early in 29.97i.
> >
> > When crossconverting (720p23.976 to 1080i29.97) the output from KONA 3 is
> > frame accurate for video and audio is approximately .4 frame early in
> > 29.97i.
> >
> > The only true solution to compensate for these types of conversions is to
> > do a separate edit for video (at conversion) and audio (with no
> > conversion), since audio can not easily be shifted accurately by less
> than
> > a frame.
> >
> >
> > On Wed, Apr 11, 2012 at 4:41 PM, Nigel Gourley <
> > avid-l@...> wrote:
> >
> > > **
>
> > >
> > >
> > > Hi there,
> > >
> > > Is this a "feature"..
> > >
> > > V6 with AJA card. HD sequence, using the secondary output as
> downconvert to
> > > standard def. embedded audio output. The audio is probably 2 frames
> earlier
> > > than the vision. And even if you switch the project to SD it's still
> out..
> > >
> > > I can understand there is a delay with the downconvert but I would
> expect
> > > the pictures and sound to be the same..
> > >
> > > I can't see this on the web anywhere..
> > >
> > > Thanks
> > >
> > > N
> > >
> > > [Non-text portions of this message have been removed]
> > >
> > >
> > >
> >
> >
> > [Non-text portions of this message have been removed]
> >
>
>
>
[Non-text portions of this message have been removed]
------------------------------------
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