Syncing audio with Cinema Display

Can someone explain how to deal with lag time when trying to sync audio and video?
I have a 23" apple HD cinema display hooked up to a G5 through a DVI connection.

Apple says this display has a response time of 16ms. Is this the same as lag time?

Will there be trouble down the road if I sync my clips using the 23" display or is that lag time imperceptible?

Is there considerable lag time going from through a firewire 400 to a Canopus box and then to a CRT television?

Thanks in advance!

-RG

Each television frame takes 33 milliseconds to complete in NTSC, 1/30 sec = .033. You need at least that much of an error to be one frame off lip sync. One frame is where the really good people can tell. You need two or three for the average viewer to tell.

Broadcast Digital Television is frequently that far off right out of the antenna into your living room due to studio, distribution, and transmitter effects. This drives friends of mine who worry about that sort of thing nuts.

<<<Will there be trouble down the road if I sync my clips using the 23" display or is that lag time imperceptible? >>>

You'll get a lot more error having the "External Video" setting wrong under the "View" header.

<<<Is there considerable lag time going from through a firewire 400 to a Canopus box and then to a CRT television? >>>

There shouldn't be. There is always a very slight delay when you go from digital to analog because of how they designed the signal in 1941, but that's really small fractions of a frame. Again, you're far ahead by just making sure your settings are correct. Final cut will either sync the external/layoff signals or the internal user monitor, timeline, and sound. You never get both.

Koz

Thank you for the response.

What if we have (2) 23" cinema displays connected. On the right display, we drag the Canvas for checking sync. The audio is coming out through the Mac's headphone jack.

Should the External Video setting be turned to off?

Will I be able to accurately check sync using this method?

-RG

Here's some info from the FAQ that might help : Sync problems

It helps but not much in this case. I am combining the actions in the first 2 sentences and that is what I'm trying to figure out. I'm viewing the video on the Canvas but the Canvas is on a 40-inch LCD tv connected through the 2nd DVI port.

"If you're playing back to an external monitor, you must also listen to the sound with an external playback device. If you're watching the image on the Viewer or Canvas, then you must listen to the sound on the computer's Built-In Audio option under Audio/Video Settings, or by turning View - External Video off (at which point Built-In Audio will kick in). If you're watching external video, for example FireWire from the computer to a deck to a monitor/TV, then you must monitor sound from the deck or the monitor/TV."