FORUMS: list search recent posts

Kona3 - Frame Playback Offset tips?

COW Forums : AJA Video Systems

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
Dave Gorrie
Kona3 - Frame Playback Offset tips?
on Apr 9, 2009 at 10:30:50 pm

Hi All,

We just upgraded to a Kona3 (from an LHe) and are having different Playback offsets then we previously did. Is there a general rule for these offsets, or is it really dependent on our decks/procs/signal flow? The LHe seemed to do fine with no playback offset on all the old layoffs (SD/HD Sony decks mosty). I found that laying off to our SRW5500 required +1, and an SD downconvert to our Digi (DVW-M2000) needed +2 with the Kona3.

We currently run everything SDI (embedded audio), simple patch bay from rooms->decks, legalizer (Harris DL860) and that's about it. Our Avids don't seem to get a throughput delay from the Harris, so I didn't think that was the issue...but maybe FCP is dealing with it differently?

Just thought I would check, I think I've got most of the decks figured out, but just wasn't sure if there was a rule of thumb for offsets (i.e. when downconverting, always add +1 on layback, or SD is always 0, stuff like that?) - and I figured this is the place folks would know!

Thanks in advance,
Dave







Return to posts index

gary adcock
Re: Kona3 - Frame Playback Offset tips?
on Apr 11, 2009 at 1:46:35 pm

[Dave Gorrie] "Just thought I would check, I think I've got most of the decks figured out, but just wasn't sure if there was a rule of thumb for offsets (i.e. when downconverting, always add +1 on layback, or SD is always 0, stuff like that?)"

Dave

I do not see different offsets between cards. I have always had differing offsets for decks.

+2 for an SRW5500 is the same as mine- but I have it set to +1 for the SRW1c (60p) deck and for the -1 for SRW 5800 so go figure. these are the same in dual link as single link and the same on my k3 vs LHe.

FYI- the kona conversion offset is ALWAYS 1 Frame - up/ cross/ down all are unified into the minimum delay possible and because most of those consist of field to frame conversion the delay is 1 frame no matter which frame rate you are passing thru and a one frame delay is considered realtime by SMPTE.



gary adcock
Studio37
HD & Film Consultation
Post and Production Workflows

Inside look at the IoHD
http://library.creativecow.net/articles/adcock_gary/AJAIOHD.php




Return to posts index

Dave Gorrie
Re: Kona3 - Frame Playback Offset tips?
on Apr 11, 2009 at 3:21:18 pm

Hey Gary,

Thanks for the insight! I kind of thought it was a little bit of trial and error based on decks, but just wanted to make sure it wasn't uh..."user error" - because that never happens!!!!

It's been a while since we've done such heavy outputs in FCP so jumping back into the fire so quickly is always fun!

Thanks again,
Dave







Return to posts index

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
© 2017 CreativeCOW.net All Rights Reserved
[TOP]