Kona 3 Output Major Playback Delay
I was wondering if anyone knows whats going on here. I sent a technical inquiry to AJA support and have not heard back yet but am posting the same problem below.
If anyone knows what the issue is or how I can compensate please let me know.
All the best, Richard
model: Kona 3
I really need some help here:
The problem I am having is that when I am playing down an edited sequence from Final Cut Pro, I (eventually) lose synch in my outputted signal from the Kona 3 to my external monitors by as much as several seconds. The audio ends up preceeding the video.
I edit using the latest version of Final Cut Pro in the Final Cut Studio package on a MacPro.
The computers specs are as follows:
o Two 2.93GHz Quad-Core Intel Xeon
o 32GB (8x4GB)
o 640GB 7200-rpm Serial ATA 3Gb/s
o ATI Radeon HD 4870 512MB
o One 18x SuperDrive
I am setup with a RAID level 5 config as well.
Currently I have 2 x 24” LED Apple monitors I use as my FCP interface workspace. I do not use the Kona for that. Instead, I am going from my graphics processing card to one of these LED monitors via mini display port. The other I had to go from DVI to mini display using the Gefen converter box.
These monitors are working fine, no degradation at all. Also, I have perfect synch in my viewer and canvas windows during playback.
I am using the Kona3 video capture card to output my video signals to the monitors - 2 in total. One for my reference and to do color correction and the other for the client.
One is a 24” HP LP2480zx Dreamcolor monitor LCD that I am going SDI-HD out from the Kona to an AJA HDP2 convertor. This takes SDI-HD in and goes DVI out. I am using a DVI-HDMI cable to go to the monitor as it has an HDMI input.
I use this monitor for color correction and so on.
The other monitor is used for client display. It’s a Samsung 42” LED HDTV with HDMI inputs. Again to get to that tv, because the Kona 3 only outputs SDI, I had to get an AJA HI5, which converts SDI – HDMI.
The mac computer is pretty much maxed out and extremely fast, so I don’t believe the issue is w/ the computer.
The problem I am having still is there seems to be a major lag between what I am seeing on my Apple LED working monitors and what is being output from the Kona.
For example- I have a 30 min documentary I edited recently which we delivered and edited in HD 1080i 60fps proress422. When I would play down an edit with the client and as the show progressed, I would be out of synch. Its like the signal is taking longer to reach my external monitors. Also I would notice that – even when editing an SD program, if I am playing down the sequence and I get to an area of the program where there is no media (black) there, it can lag behind as much 2-3 secs.
I don’t know if there is something I am doing wrong or if there is a setting to adjust this or what.
I have installed the latest drivers for the Kona 3 but the NDD version because my computer would not wake from sleep with the normal driver.
I realize this is a ton of info but I know no other way, other then getting a tech here in our offices.
-Richard Tarantino, EVTV Editor
Yes this can be frustrating. The way to fix this is to put a "slug" on Video track 1 under everything.(Effects/video generators) Any time there is a "black space" on the time line with no media, the Kona gets confused. Just make sure there is a black slug under everything and you will see this go away. A pain I know, but once you get used to working like this, it is not a problem.
Hope this helps.
FrostLine Productions, LLC
[Richard Cooper] "The way to fix this is to put a "slug" on Video track 1 under everything.(Effects/video generators) Any time there is a "black space" on the time line with no media, the Kona gets confused"
This is an wholly an FCP issue,it happens with FW also, especially when your audio has been handled in a compressed manor as is the case when working with HDV or the H.264 originals from DSLRs when using the RTX processing engine in FCP.
When working with compressed audio the engine has to process the audio signal for playback, and when there is nothing in the timeline the processing jumps to the next edit point and begins processing, in this case since the video does not need processing- the audio lags behind because it does.
Post and Production Workflow Consultant
Production and Post Stereographer
"When working with compressed audio the engine has to process the audio signal for playback, and when there is nothing in the timeline the processing jumps to the next edit point and begins processing, in this case since the video does not need processing- the audio lags behind because it does."
This makes sense Gary. The weird thing is that when I leave "holes" in my video time line the video actually starts to "lag behind" and not the audio. Maybe something to do with the audio sample rate and FCP confusion? At any rate, I no longer have these issues once I started working with Slugs to replace the "holes" in the time line.
FrostLine Productions, LLC
Thank you for the response. I filled my gaps w/ a slug and it fixed all issues.
I appreciate your help in this matter.
Thank you so much for the response. Yes, I put the slug in and that did fix the problem.
I really appreciate you taking the time to address this.
All the best,