Kona 3 downconversion timecode slip

[Gary Adcock]

[Joey Burnham] “Working with 1080sf23.98 uncompressed 10 bit material.
When I downconvert to digibeta ntsc my video is not frame accurate… Usually my video/audio comes in about 4 frames earlier than it should, but this number can vary.”

All 23.98 content is Non-Drop.
Standard def footage is usually drop frame.

you need to compensate for the time difference.

gary adcock
Studio37
HD & Film Consultation
Post and Production Workflow for the Digitally Inclined
Chicago, IL

[Joey Burnham]

I wish it were that simple. We work NDF here so that’s not it. I talked to Jerry @ AJA and he said to switch my device control preset in my HD setup to 29.97. I tried that but then I was coming in 2 frames late.
stumped.

[Gary Adcock]

[Joey Burnham] ” tried that but then I was coming in 2 frames late.”

All conversions takes one frame ( 2 fields) to complete and that is considered realtime.

you can change the timecode offset in the FCP’s AV prefs > device control

[Joey Burnham] “We work NDF here so that’s not it. “

confirming that you lay SD to tape as NDF also

gary adcock
Studio37
HD & Film Consultation
Post and Production Workflow for the Digitally Inclined
Chicago, IL

[Joey Burnham]

[gary adcock] ”
confirming that you lay SD to tape as NDF also”

Confirmed.

Does this mean that I need to change my offset every time I do a downconversion? Laying back HD is fine.

[Joey Burnham]

If I set my device control preset to 29.97 and my offset to +2 it’s getting as close as I can get. It’s coming in on though on the 2nd field though, and my offset won’t let me put in +1.5 (even though my capture is 1.5)

[Jesse Coane]

is this documented anywhere? I called aja about this when we first got the LHI and they acted like they never heard of this and that something was wrong with out setup. I’ve done test after test trying to isolate the issue.

thanks

jesse

Jesse Coane
Director / Editor
The Concept Farm

[Joey Burnham]

I just reread the manual and found nothing. Ever since I installed the latest drivers I’ve had to make changes to my workflow. I no longer can work in the 1080p23.98 preset but have to work in the 1080sf23.98. Also when downconverting I made an easy setup which switches my device control preset to AJA 525i 29.97 with a playback offset of +2.
Seems to do the trick but not perfect.
Joey

[Gary Adcock]

[Joey Burnham] “Ever since I installed the latest drivers I’ve had to make changes to my workflow. I no longer can work in the 1080p23.98 preset but have to work in the 1080sf23.98”

What’s the issue? the default for all post in 1080 is PsF, cameras shoot progressive, but the playback is interlaced.

And Yes, installing new drivers or a new version of FCP would trash all your old pref files,

[Joey Burnham] “Also when downconverting I made an easy setup which switches my device control preset to AJA 525i 29.97 with a playback offset of +2. “

thats a lot, but I have even had offsets up to 5 frames.

As before, the conversion process takes one frame, and having a deck offset by one frame is not that out of the ordinary so I do not see what the issue is, other than you had to retune your capture playback settings and yes this setting would have been in those trashed prefs also.

gary adcock
Studio37
HD & Film Consultation
Post and Production Workflow for the Digitally Inclined
Chicago, IL