Lip Sync way off for imag

Here's our setup

INPUT Side:
ATEM 1M/E
2-3 Panasonic AG-AC160 Camcorders via SDI @ 1080i 59.94
1 TVOne 1T-VS-658 Video Scaler for VGA conversion via HDMI @1080i 60

OUTPUT: 1080i 59.94
40" Samsung LED LCD panel for MultiView via HDMI
2 Eiki LC-80 projectors (1024x768) via Component through Extron Component DA

Audio is coming from a Yamaha LS-9. We have tried running audio through the switcher and completely separate. Neither way seems to be any better. When we run through the switcher we get a nasty hum(audio, switcher and PA are all on the same power).

The problem that we are seeing is that the lip sync on the imag projectors is WAY off, not just a frame or two but very noticeable. From what I am reading it seems that we should only be 2-3 frames off. 1 frame for the frame sync since all of our sources are not able to take sync. Depending on who you talk to we may be losing a frame on the component out. We are not using any DVE's or USK's so we should not be losing any time there.

We have delayed the audio by .85milliseconds and that gets us very close, the problem with doing that in a live situation is that you can actually hear the delay between the person speaking on stage and the sound coming from the PA.

Anyone see where we might be getting the extra delay?

[Sarah Jones]

You might look into how much delay the TVOne scaler introduces as that's an analog to digital conversion as well as an upconversion, and those types of conversions can add in extra delay on the front end. However, if you're delaying .85 milliseconds and getting really close to sync, that sounds about right for 3 frames of delay (29.97fps = roughly 33 milliseconds per frame).

Not so strange:
2-3 Panasonic AG-AC160 Camcorders via SDI @ 1080i 59.94 into ATEM 1M/E without ref =1 frame
1 TVOne 1T-VS-658 Video Scaler for VGA conversion via HDMI @1080i 60 for the powerpoint? If so not an issue.

OUTPUT: 1080i 59.94
ATEM to Extron Component DA might be again one frame
2 Eiki LC-80 projectors (1024x768) Will be scaled down so that takes time again.

If you want to do this right you need to ref the cameras to the atem, then go from the ATEM to a professional projector like a Christie/DP that can take the ATEM signal and can project the image with minimal latency.

My bet is the ATEM actually is the fastest device within your signal path at this moment.
The cameras you use have no genlock input, so they are not the best choice for this sort of a job.

1 TVOne 1T-VS-658 Video Scaler for VGA conversion via HDMI @1080i 60 for the powerpoint? If so not an issue.

We actually use ProPresenter but for slides and still images this is not an issue but sometimes we roll playback from ProPresenter through this so I will need to check on what delay it may introduce.

2 Eiki LC-80 projectors (1024x768) Will be scaled down so that takes time again.

Would we do better to come out of cameras and switcher in 720 so that the projectors are not scaling as much?

BTW, we know the best way to do this but we do not have an unlimited pool of resources and neither do our clients. Sometimes sacrifices have to be made. We are just trying to make the best of them!

My suggestion is to test with other projector options where you do not have to scale at all and they have native 1920X1080 resolution. (like the optima hd20) and see if this helps.

Sharyn

We have found that using 720p throughout our system gives noticeably less latency than 1080i.

On the newer Sayno PLC XM series of projectors there is an option to reduce the latency, at the expense of keystoning and other functions.

I am not sure if the Sanyo XP100 (same as your Eiki) had this but may be worth checking.

Tim

hey, we found out that the panasonic recorder has an extra delay on the sdi output with about 160ms. Panasonic tested it and confirmed it to us. we found this out when we where using the panasonic and jvc gy-hm750 at the same time. the panasonic was always behind.

and yes shure the atem also adds a delay.

for this reason we'll sell all our panasonic recorders

We have found that using 720p throughout our system gives noticeably less latency than 1080i.

This turned out to be the best solution.

Buying new projectors is not an option so for now we will just do 720, 99.9% of our audience can't tell the difference anyway.

Its worth noting that 720p is generally faster due to the higher frame rates, one frame of delay @ 50FPS = 20MS @25FPS it would be 40MS.

I have XP200s here and have also found that the performance with 720p sources is the best. We are running at around 80-100MS latency (depending on the precise signal path) - pretty acceptable really. One thing i did find when testing all this is that the sanyo digital inputs have fractionally less latency than the VGA / RGBHV inputs. We still run VGA though as we have legacy routers and won't bother upgrading all the cable to fibre until we have better projectors.

When we upgrade to widescreen projectors with native 720p capabilities I expect the latency to improve once more.