Synchronising different video pathways

[FL K]

Hi there,

Chasing some experience from the community around synchronising content across vastly different signal paths and devices; Any hints/suggestions welcome. Here the scenario:

1x on-Stage TV, 

1x projector doing some projection mapping,

both running 1080P50/60, both at times showing the same content (and sometimes different content)

Source is a Mac Studio M2 Ultra;

Signal path options I am considering:

For the Projector (Panasonic RZ690):

Either

HDMI > BMD HDMI to SDI 3G Micro Converter > 3G-SDI cable > Projector 3G-SDI in

or

TB > BMD UltraStudio Monitor 3G > > 3G-SDI cable > Projector 3G-SDI in

or 

TB > adapter USB-C to HDMI > BMD HDMI to SDI 3G Micro Converter > 3GSDI cable > Projector 3G-SDI in

For the TV:

TB > adapter USB-C to HDMI > BMD HDMI to SDI 3G Micro Converter > 3GSDI cable > BMD SDI to HDMI 3G Micro Converter > HDMI port of TV

or 

HDMI > BMD HDMI to SDI 3G Micro Converter > 3G-SDI cable > BMD SDI to HDMI 3G Micro Converter > HDMI port of TV

or

TB > BMD UltraStudio Monitor 3G > > 3G-SDI cable > BMD SDI to HDMI 3G Micro Converter > HDMI port of TV

Since there is only 1x HDMI port on the MacStudio, there will be at the very least that difference if I were to use it, but of course also the input processing time of the signal at their destination, as I can go straight 3G-SDI into the projector but not the TV;

There is also the option of using

HDMI > AJA https://www.aja.com/products/ha5-4k > 2x 3G-SDI > 2x BMD SDI to HDMI 3G Micro Converter > both HDMI ports of TV and projector,

For while that might not be the lowest latency pathway, at least it would be consistent bar the signal processing inside the two outputs.

What do folks do out there in similar situations? And, if I find noticeable differences in latency in the 2 outputs, is there a way to do something similar than delaying audio for video in QLab, on a per-output-basis? (I guess alternatively one could do it on a per-cue-basis if I were to replicate cues that appear on both outputs, a bit more busy work).

Thanks for your help in advance, if I had my hands on all the gear already, I'd just run tests, but part of this is about buying decisions, so if there are insights influencing those, that would be incredibly helpful.

Appreciated!

Freddy 

[christopher....@gmail.com]

I’ve always used USB C to HDMI adapter> HDMI over network (Cat 6 works well)> HDMI out to the TV or projector. Never had any latency issues. Always used the exact same adapters. Differences in the Cat 6 cable up to 50’ without issue. 

I would suggest staying away from using different adapters or different cables. Those are times I’ve seen noticeable differences in latency. 

Also considering content is important. Are you syncing visuals with audio? Especially showing someone’s face while speaking. Our brains are fine tuned for that and so even the smallest amount is perceptible. I wouldn’t worry too much about having noticeable latency issues between different video outputs unless you use different cables. 

Use the HDMI out on the Mac as your control monitor. 

Chris

Sent from my iPhone

On Jan 25, 2026, at 5:03 PM, FL K <busy...@gmail.com> wrote:

Hi there,

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[Sam Kusnetz]

Unless the projector and the TV can be genlocked together, true 100% sync between them is impossible.

Given that, using a display divider like the AJA HA-5 will give you the best chance of sync, because as far as the Mac is concerned, it’s rendering a single display, which is of course always in sync with itself.

Best

Sam

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[FL K]

Thanks Sam and Christopher,

I think I'll go with the AJA and replicate the signal flow as much as possible across the entire chain;

Lipsync wise (which, yes, is going to be a thing), I'm looking at using Voxengo Sound delay on the audio output as a whole - so as long as I only need to sync to one video source (or they are at least close, and I'll go "in between"), we should be fine, assuming that it would be very unlikely for the vision to have less latency than the sound :).

Cheers,

Freddy