FORUMS: list search recent posts

JVC HD monitor latency

COW Forums : AJA Video Systems

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
Gordon Gurley
JVC HD monitor latency
on Sep 17, 2007 at 4:07:38 pm

Sorry, off topic. I just got a JVC DT V24L1D, hooked to the second SDI output of my Kona LHe. There is about 1 to 2 frames of latency between audio from Kona and picture on JVC. Output 1 of the Kona (which goes to my machine room) looks fine.

I guess I can try switching the cables, but my suspicion is that it's the monitor. Anyone else notice this?

Thanks,


Return to posts index

walter biscardi
Re: JVC HD monitor latency
on Sep 17, 2007 at 4:18:03 pm

That monitor may require an offset like our Panasonic Pro Plasmas.

In 720p I leave the Playback Offset at 0. In 1080i, I have to change the offset to 2.

So if you have a two frame lag, change that offset.

Walter Biscardi, Jr.
http://www.biscardicreative.com
HD Editorial & Animation for Broadcast and independent productions.

All Things Apple Podcast! http://cowcast.creativecow.net/all_things_apple/index.html

Read my blog! http://blogs.creativecow.net/WalterBiscardi


Return to posts index

Gordon Gurley
Re: JVC HD monitor latency
on Sep 17, 2007 at 4:29:52 pm

Hmm, but that seems a little scary. If I offset to match my monitor, my audio will be out of sync when it hits my deck. I'd hate to have to switch it every time I do a layoff. Is there a way to set up different offsets for each output of the Kona?



Return to posts index


David Roth Weiss
Re: JVC HD monitor latency
on Sep 17, 2007 at 4:35:03 pm

[Gordon Gurley] "I offset to match my monitor, my audio will be out of sync when it hits my deck."

There's nothing really changing, just the apparent relation between video and audio to correct for the monitor latency. Its not really making a shift between the two as in actually slipping audio and video.

David Roth Weiss
Director/Editor
David Weiss Productions, Inc.
Los Angeles

POST-PRODUCTION WITHOUT THE USUAL INSANITY


Return to posts index

Gordon Gurley
Re: JVC HD monitor latency
on Sep 17, 2007 at 4:42:39 pm

OK wait a minute, how will the offset (i'm assuming your talking the playback offset in FCP) make my Kona monitor match my Kona audio? It has no effect.


Return to posts index

walter biscardi
Re: JVC HD monitor latency
on Sep 17, 2007 at 4:46:46 pm

[Gordon Gurley] "OK wait a minute, how will the offset (i'm assuming your talking the playback offset in FCP) make my Kona monitor match my Kona audio? It has no effect."

The offset puts a slight delay in the way the video is received by the monitor so it puts your audio and video back in sync for viewing purposes.

Record to tape is not affected at all.

Walter Biscardi, Jr.
http://www.biscardicreative.com
HD Editorial & Animation for Broadcast and independent productions.

All Things Apple Podcast! http://cowcast.creativecow.net/all_things_apple/index.html

Read my blog! http://blogs.creativecow.net/WalterBiscardi


Return to posts index


Gordon Gurley
Re: JVC HD monitor latency
on Sep 17, 2007 at 4:52:36 pm

I'm missing something here. FCP Playback offset only affects the desktop sync. It doesn't seem to do anything to Kona output (thank god). What offset delays the audio from Kona to match a slow monitor?

Please put me straight if I'm missing something here.


Return to posts index

walter biscardi
Re: JVC HD monitor latency
on Sep 17, 2007 at 5:00:11 pm

[Gordon Gurley] "FCP Playback offset only affects the desktop sync. It doesn't seem to do anything to Kona output (thank god). What offset delays the audio from Kona to match a slow monitor?"

It affects the audio sync to picture. In your case, the JVC monitor sounds like it requires 1 or 2 frames to display the image correctly, just like my Panasonic Plasma requires 2 frames to correctly display 1080i material. So by adjusting the playback offset, you put your external display in sync with audio.

Walter Biscardi, Jr.
http://www.biscardicreative.com
HD Editorial & Animation for Broadcast and independent productions.

All Things Apple Podcast! http://cowcast.creativecow.net/all_things_apple/index.html

Read my blog! http://blogs.creativecow.net/WalterBiscardi


Return to posts index

David Roth Weiss
Re: JVC HD monitor latency
on Sep 17, 2007 at 5:11:41 pm

Gordon,

Here's the deal...

The Frame Offset setting in the System Settings--Playback Control doesn't really change sync between audio and video, it just changes "apparent" relationship bewteen the two when monitoring through FCP both on the FCP desktop and through the Kona card. Unfortunately, some monitors require a setting that is not perfect for for both. In that situation you must chose which is more important to you, perfect sync on your client monitor or perfect sync on your FCP desktop. Does this make sense???

David

David Roth Weiss
Director/Editor
David Weiss Productions, Inc.
Los Angeles

POST-PRODUCTION WITHOUT THE USUAL INSANITY


Return to posts index


Gordon Gurley
Re: JVC HD monitor latency
on Sep 17, 2007 at 5:24:07 pm

Yes, thank you.


Return to posts index

Bob Zelin
Re: JVC HD monitor latency
on Sep 17, 2007 at 10:20:23 pm

Hi Gordon -
the 24" JVC is a great monitor. All the LCD's and Plasma's have delay issues like you are seeing. The people that say "I don't have any problems" can't see a 1-2 frame delay error. CRT's never had propogation delay issues.

bob Zelin


Return to posts index

Gordon Gurley
Re: JVC HD monitor latency
on Sep 17, 2007 at 10:26:07 pm

Thanks Bob. I think my only way around this is to use the embedded SDI audio and use the rca audio out jacks on the monitor. The audio coming out of the monitor at least seems to be in sync with the picture.

A little wrinkle that nobody seems to be talking about.


Return to posts index


Bob Zelin
Re: JVC HD monitor latency
on Sep 17, 2007 at 10:35:08 pm

I just did this with the Panasonic 42" Plasma at Brighthouse Networks in Florida. I sent video into the monitor, and take the audio out from the monitor to get a "non delayed" audio signal. (Cheaper than buying the RANE AV22d delay line).

Bob Zelin


Return to posts index

jesenko
Re: JVC HD monitor latency
on Oct 7, 2007 at 6:47:06 pm

Does this mean that the Panasonic Plasma has a delay in processing the audio as well as video? It would seem so.

I have a FCP/Kona3 setup with Sony CRT broadcast monitor (in perfect sync with Kona audio) and a Pany Plasma client monitor which is about 2 frames late. Adjusting the Playback Offset can get my desktop monitor in sync with the Plasma but it's still out of sync with Kona audio and it makes it impossible to edit like that.

What would you suggest I do in my setup? I am thinking about putting in an audio delay unit and engaging it only when a client needs to review a cut.

Thanks for any feedback.

//Jesenko @ eclipse in Atlanta


Return to posts index

Bob Zelin
Re: JVC HD monitor latency
on Oct 8, 2007 at 12:43:44 am

you can't have EVERYTHING in sync, no matter what you do. There are inherent propogation delays in the LCD monitors and Plasma monitors that are all different. So you can setup audio delays (like the RANE AD 22d) to make the Panasonic Plasma correct, but then the audio out of the RANE will be out of sync with your CRT. YOU CANT HAVE EVERYTHING. Don't think that if you bought "brand x" instead of "brand y" your problems would be gone. Everyone faces these issues, and all the products have slightly different delays. Those that say "gee, I don't have any of these issues" don't know what to look for. (Ignorance is bliss).

Some of the Panasonic Plamsa displays have audio outputs. If you let the embedded audio go into the monitors, the audio outputs have the correct delayed signal (so you dont' need the RANE delay, for example) - but remember, when you monitor the straight output of your AJA or Blackmagic product, it won't be in sync - and neither will your Apple 23" cinema display.

Bob Zelin


Return to posts index


John Pale
Re: JVC HD monitor latency
on Sep 18, 2007 at 4:20:46 pm

An Avid based facility that I freelance in frequently has digital delays installed on their audio monitor outs from the mixer to compensate for this lag.


Return to posts index

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