# Zero Latency Video of Conductor



## neergmas (Jan 13, 2015)

I work at a college and my day-to-day is managing the video studio and equipment for the communication department, but my undergrad was in theatre, so when the theatre dept. puts on a musical and wants video monitors for the conductor & cast, I get to cross the street and play in the space I want to be in. 

The usual set up that they've gone with since I've been here (this is my 4th year) is the band not in the pit, but rather upstage center, hidden quite a bit by the set. The conductor faces the back wall of the stage, so cueing the actors is impossible without video intervention. The trouble is that there's latency between the conductor's hands coming down on stage vs. what's seen on the monitor. 

The set up that they had in place before I was hired and that I've been replicating since is as follows:
There is a flat screen tv mounted over the house, accessible from a catwalk. There is an RCA cable to the TV, which we run through a BNC connector into a Phat Cat system. The 500' cat5 (the length specified by the Phat cat unit) from that runs to the phat cat transmitter which is in the orchestra area, and there is a canon FS300 videocamera, with composite out, connected to the transmitter via another female RCA to M BNC connector. I have also had to split this signal via an RCA splitter to have a video monitor in the wings for supporting singers huddled around a mic in the wings.

Then for the conductor, I've got the same sort of system in reverse. The camera is up in the catwalk over the house near the TV, offering a birds eye view of the stage, and it all has the same cables, save that I have a small CRT monitor (cast offs from our TV studio's recent HDMI monitor upgrade) so from the Phat Cat receiver to the conductor's monitor, the connection is a BNC cable, no adaptor needed/used.

I'm working on memory from years past, and I believe there was no latency with the run from the camera of the conductor to the back stage monitors, nor any trouble with the conductor's monitor from the catwalk camera feed.

From what I piece together, the latency trouble is there because of the new TV we're using, am I correct? My predecessor had them rent the tv the first time he set it up, and then they bought it, as they assumed they'd want to use it each semester.

I anecdotally recall during my undergrad that we bought a security camera system from walmart and set that up, using long RCA cables, like 100' or more (i think) and they worked great, no trouble with the white balance with lights at full or blackout, perhaps it was a system made for looking in the dark, I recall we needed it for blackouts so that they would know actors were in place. This was over 10 years ago, so perhaps the reason I remember it working so well is that it was all "old" tvs?

So are there any suggestions, ideas, reading materials, etc on what I can do so that when the conductor gives a down beat, it's in real time on the monitor for the actors? Is it the panel tv, and should I be thinking of a way to stick some sort of "older" tv somewhere? I can take pictures of the space if it helps, because I cannot think of a place to stick a monitor where it isn't in sightlines and easily visible for actors. If you've done this and have or can take pictures, I'm wide open for suggestion!


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## robartsd (Jan 13, 2015)

My guess is that it is the analog to digital conversion in the panel TV that is causing the latency as it sounds like the rest of your system is all analog.


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## Morte615 (Jan 13, 2015)

Yep the biggest problem here is the Analog to Digital conversion. My suggestion (if possible) would be to use BNC Coax cables as much as possible. Look into security style systems that can have BNC out of the cameras and look for a decent size monitor that has BNC (or RCA, adapters for BNC to RCA are easy to find) input. You can still get high def picture and the latency will be a lot less.
Though getting to 0 latency will cost a lot of money, cable lengths and any devices in the way will cause latency. The trick is mitigating that latency to something manageable.


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## AlexDonkle (Jan 13, 2015)

Is the Phat Cat system an active transmitter (i.e. requiring power) or just a passive balun (i.e. no power needed)? If it's just a passive box, then it's that's likely fine as-is and not causing any latency.

As mentioned, any analog-to-digital conversion is a potential issue. With CRT's, an all analog system works fine, including with passive baluns. Flat panel TVs always require a digital signal, including if you feed analog composite BNC/RCA video directly into the display, the TV will just convert the analog video into digital internally before it appears on-screen. If the TV's conversion is fast enough, this might work for you, but if not you'll need to convert the signal to digital with an outboard box somewhere, rated for zero latency.

If you have flat panel TV's, the best solution is using an all digital system starting with digital cameras outputting SDI or HDMI, and then transmitting that digital signal to the displays without using any analog. Professional monitors with SDI inputs typically have zero latency, but consumer flat panels using HDMI may depending on the model. displaylag.com actually measures and posts the latency of various displays when fed a digital signal, it's gotten better over the past few years. There's no data I know of for measuring the latency of displays when fed an analog signal though.


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## neergmas (Jan 14, 2015)

Thanks for the help so far, it's helping me process ideas. The phat cat system is powered. Caused me some headache last year as one of the power supplies went missing and it uses the oddest thing, 4 pin cable like a color scroller power supply...

As the flat panel tv that's hung is in a great spot, easy for actors to see and out of audience sight, i think I'd like to be able to stick with that. In theory, I can stick to analog cameras for the conductor's small monitor of what's going on onstage, and perhaps get them to invest in a small panel tv monitor for backstage (and dare i suggest another downstairs in the green room?) 

The trouble I see then is running the signal from the camera pointed at the conductor to all my other monitors. I know hdmi cable really doesn't like more than about 25/50 feet, and in our classroom tech installs, we use hdmi over cat 5. As we set this up each semester, perhaps I can get it to where I can leave permanent runs for the tvs and just need to plug in some cables.

Thank you for the link, @AlexDonkle I'll check out the panel they have up there. Though I'm really hoping they have the manual or something accessible, because I don't fancy needing to go up 20 feet in the air to squint for a model number on the back of this thing!


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## robartsd (Jan 15, 2015)

Digital equipment is much more likely to add latency than analog equipment. A major reason for this is that digital signals are much easier to buffer. So as you develop an all digital path, you'll want to keep latency in mind for every piece of equipment. Converting between ditigal and analog (either direction) tends to be among the highest latency processing.


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## leistico (Jan 27, 2015)

I use a video assist for the conductor and for the performers onstage at my theatre. Usually there's a wall between the two onstage (for set and/or sound purposes - we're a small community theatre, 150-seat house) so I have two independent systems.

For the performers: an old Sony Handicam with "night vision" on a tripod aimed at the conductor - composite video into an rf-modulator type of thing that converts it to ch.3 video - down about 150' of coax cable - to an old VCR set to ch.3 converting it to composite video out - to a Vivitek consumer-type video projector shooting on the wall above and behind the top row of the audience. We call it "Big Martha," as Martha is our music director that uses it the most and, well, it's a big bright picture, easy enough to see looking over the audience and below the front lights, and it keeps performers who need the cues facing out and up, which makes a nice stage picture.

For the conductor: a $40 Win-something security camera with infrared positioned so that it gets a great look at the whole stage from one side of the house - down about 100' of whatever cable it uses (has composite video and camera power all in one cable) - to an old CRT TV on a school-type AV cart usually just on the other side of the drums in the backstage "pit" facing the conductor. I set up the shortened camera tripod for the conductor on the same cart right next to the TV (bless you, gaff tape), so it's almost like local area video conferencing - one can see the other seeing the other.

For mostly found-in-a-closet parts and a quick prayer to St. MacGyver, it's worked pretty well for a few years now.


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## ElGusto (Jan 28, 2015)

I used to work at a conservatory that did quite a bit of opera, and the conductor monitoring system was always a pretty big head ache once we moved into digital/ flat screen displays. All digital systems have some degree of latency by their very nature. In order to get the system to acceptable levels all signal distribution was done via composite analogue (bnc) cable run through a composite video amp/splitter every couple hundred feet. Basically using the same cctv tech from the 90s @neergmas mentioned above. Any camera with an analogue out will serve, but your tv monitor will have some degree of latency as long as it is digital. Check out the Wikipedia page on display lag. Www.En.wikipedia.org/wiki/display_lag


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## Amiers (Jan 29, 2015)

leistico said:


> I use a video assist for the conductor and for the performers onstage at my theatre. Usually there's a wall between the two onstage (for set and/or sound purposes - we're a small community theatre, 150-seat house) so I have two independent systems.
> 
> For the performers: an old Sony Handicam with "night vision" on a tripod aimed at the conductor - composite video into an rf-modulator type of thing that converts it to ch.3 video - down about 150' of coax cable - to an old VCR set to ch.3 converting it to composite video out - to a Vivitek consumer-type video projector shooting on the wall above and behind the top row of the audience. We call it "Big Martha," as Martha is our music director that uses it the most and, well, it's a big bright picture, easy enough to see looking over the audience and below the front lights, and it keeps performers who need the cues facing out and up, which makes a nice stage picture.
> 
> ...




I would love to see pictures of it, as it sounds quite interesting.


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## om4eccv (Jan 29, 2015)

I've purchased a bunch of stuff off of eBay, and repurposed a lot of stuff from my day job, when we replaced older cameras with newer ones. Yay community theatre. 
I've got a video rack we roll into the 1100' space we rent. It's got switchers and Distribution Amps and Quadframers and everything we need. Everything is analog because of the latency issues. 

Standard setup is:

FOH cam in the lighting booth. It's an Extreme CCTV EX-82, now owned by Bosch. It's analog, with a pretty powerful IR flood built into it. Designed for up to 400' outdoors, it washes the entire stage/room in IR light.
Conductor cam is a Fisheye cam that was designed to be an aftermarket backup camera in a vehicle. We've put this behind the conductor (18" behind their head) and it shows from the conductor's knees up to the first electric. Lately we've been putting it on the front edge of the stage, facing the conductor. 
SR Cam - sits on top of the SR speaker stack. Small bullet-style cam, but does have it's own (weak) IR illumination. Shows from SR proscenium to OSL wall. 
SL Cam - sits on top of the SL speaker stack. Small bullet-style cam, but does have it's own (weak) IR illumination. Shows from SL proscenium to OSR wall. 

Upstage wing cameras as-needed, showing aerial fly crew, or anything the SM needs to watch. 
We've got a triple LCD Marshall rack, each with 2 inputs. We can only view 3 cameras at once, but can A/B between inputs for a total of 6 cameras. 
We've got a couple other monitors we can toss up, if needed. All have BNC. 
We've got a bunch of RGBHV BNC cable, which allows 5 composite signals. Rental houses are selling it off in favor of CAT5 solutions. You can get 100' chunks pretty cheap. 

We'll always use the FOH cam. Sometimes we've got no SM, so the LX Op is calling the show. They get a monitor up in the booth, and simply use the camera to watch the stage during blackouts. These shows have little to no set pieces, maybe a drop, and some props. 
Conductor and SL/SR cams get used if there's an orchestra and many set pieces.

If there's a bunch of off-stage choral parts, I'll bounce a projector off a wall OSL for the choir. (The venue's OSL is a wing, with an 8' wide x 20' tall opening to the stage.) Said wall is hidden from audience view. 

We can quad-frame any combination of the cameras, and route them to the house's green room/makeup room. It adds latency, but those displays don't matter. 
If there's a crazy amount of kids offstage (Aladdin Jr, etc) they're in another room 60' from the green room, so I throw up a 42" LCD and let them watch the show from there.


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## Jay Ashworth (Jan 29, 2015)

I assume you're not using IR for hearing-impaired?


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## JFutty90 (Jan 29, 2015)

So, I am slightly confused here. If there is any latency, it should only be a few ms. So much so that it shouldn't really be that much of a problem unless the actors are having that much of a reaction time issue. Even allowing for the physics of sound to reach the actor. That time would be longer than the delay of the video system. So there must be some delay in the Phat Cat system not just the monitor.

To get rid of this issue, you could go to an all digital system. The less expensive system would use Cat5e or Cat6 cable, but would require two separate runs that have to be plugged into the correct jack every time. Easy to get around by labels or leaving it permanently together. The other, and definitely more expensive option would be using HDMI to SDI via mini converters like BlackMagic or AJA. We use them for IMAG and video systems for large conferences and I can't say that I have seen lag, at least not noticeable. Max run for SDI however for this signal is 250' I believe. You can put a re-clocker for the SDI in the middle if you need a longer run, but from what it seems, 250' might be enough. You would however need power for these converters as well where there are Cat5/6 converters that I think don't require power (not actually sure how that works though) but the ones Monoprice has is a max length of 98' from what I have read. I am not sure how you would extend that to be the distance you need, but I am sure there is a method to do that.


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## om4eccv (Feb 2, 2015)

Jay Ashworth said:


> I assume you're not using IR for hearing-impaired?


Nope. 49Mhz FM system.


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## om4eccv (Feb 2, 2015)

The most recent video I saw where this was evident, was a lip sync battle on Jimmy Fallon. Watch the IMAG behind everyone.

Lip Sync Battle with Will Ferrell, Kevin Hart and Jimmy Fallon:


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## themuzicman (Feb 2, 2015)

JFutty90 said:


> So, I am slightly confused here. If there is any latency, it should only be a few ms. So much so that it shouldn't really be that much of a problem unless the actors are having that much of a reaction time issue. Even allowing for the physics of sound to reach the actor. That time would be longer than the delay of the video system. So there must be some delay in the Phat Cat system not just the monitor.



You'll find that actors seem to notice the latency on a flat-panel display when the conductor is also visible in the pit - they can see the real downbeat in person and also the video downbeat on the screens and it doesn't line up and there are complaints. 

It may be shocking, but the Broadway and Off-Broadway markets are still using analog systems and a lot of them still use huge CRT monitors hung in the house for the conductor shots. We see a lot of cameras like the Panasonic WV-CP500 for FOH shot and the Vitek VTC-EBV49/24H for Conductor (they are simply ordinary analog cameras with standard composite output) all connected via RG59 BNC or Cat5 via a BNC to Cat5 Balun with some boring BNC VDA's thrown in the mix to power the signals. Latency is in fact in the flat panel displays - the more costly the display traditionally the lower the latency. I still prefer hanging large CRT monitors everywhere just because they are inexpensive and work just fine.


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## AlexDonkle (Feb 3, 2015)

themuzicman said:


> Latency is in fact in the flat panel displays - the more costly the display traditionally the lower the latency. I still prefer hanging large CRT monitors everywhere just because they are inexpensive and work just fine.



The high latency problems for flat panels mostly occur when feeding an analog signal into a flat panel TV and it gets converted to digital before displaying, or if the display's internal processing or scaling are activated. Unfortunately using a 100% digital signal from camera to TV is still much more expensive than Cat5 Baluns and analog VDA's, so it tends to be impractical in many cases. 

The display latency of many gaming monitors when fed a digital signal is around 10ms which is essentially imperceptible. There's been a decent amount of research over the past few years about maximum latency values for live music at it relates to music performance over video-teleconferencing systems, which is similar to a remote orchestra. For real-time music a max latency of 25ms was generally agreed to work well with most musicians. For reference a single frame of video is 33ms.


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## Chris15 (Feb 3, 2015)

The problem is that in many cases one cannot turn off the internal processing, scaling etc...


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## Jay Ashworth (Feb 4, 2015)

AlexDonkle said:


> For real-time music a max latency of 25ms was generally agreed to work well with most musicians. For reference a single frame of video is 33ms.



Except that we're talking about NTSC analog here. And while we *call that* 480i30, what it is in the real world is 240p60. So what matters is the field time, and that's half, or 16ms.


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## ruinexplorer (Feb 4, 2015)

Although you usually can't turn off internal scaling, you can minimize its effect on latency by sending the display its native resolution. Once it discovers that it doesn't need to process the signal in that fashion, it will usually not process the signal.


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## Gambino (Mar 6, 2020)

Morte615 said:


> Yep the biggest problem here is the Analog to Digital conversion. My suggestion (if possible) would be to use BNC Coax cables as much as possible. Look into security style systems that can have BNC out of the cameras and look for a decent size monitor that has BNC (or RCA, adapters for BNC to RCA are easy to find) input. You can still get high def picture and the latency will be a lot less.
> Though getting to 0 latency will cost a lot of money, cable lengths and any devices in the way will cause latency. The trick is mitigating that latency to something manageable.


Hey sorry to interrupt! But how much money would cost to have 0 latency? What kind of equipment?


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## macsound (Mar 6, 2020)

SDI has the lowest latency of digital video but each device still has to process the video to some extent.
LCD TVs now have game mode which reduces processing and processing time and BlackMagic studio cameras have (I believe) the lowest latency.
Overall with something like a $500 vizio tv in game mode and a $1200 BM studio camera, you should have about 5 total frames of latency. At 60fps, that's fairly small. 
Otherwise, analog.


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## Jay Ashworth (Mar 6, 2020)

The only way you can have "zero" latency (actually, a line or two), is to go all-analog NTSC.

If you go digital at *all*, you are at the encoding latency of the MPEG hardware encoder, and the *theoretical* minimum latency there is 1 frame or 2, depending on how you do the math; it is *impossible* to get "zero" latency if anything is digital.

There's a decent likliehood that *any* flat-panel display is going to introduce at least one additional frame of latency, as it has to digitize entire frames of incoming NTSC/analog, as well.


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## Gambino (Mar 6, 2020)

I’ve been searching for zero latency for ages knowing that zero latency is something impossible to achieve, but all the topics are a bit misleading and I started to believe there was a zero latency holy grail. But soon reality kicked in! I’m doing this show with 2 cameras live in a play, so latency is a big issue between live sound from the actors and the live feed from the cameras being projected. We are rehearsing at the moment and instead of anprojection we’re using a big screen tv to see what we shoot and the latency that the tv adds is mindblowingly huge! I haven’t tested the actual projector we’re going to use but i’m crossing my fingers that the latency doesn’t become a problem. We’re using SDI from cameras to a blackmagic atem tv studio, the output is also sdi!


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## macsound (Mar 6, 2020)

Projectors will generally have a far higher latency than tvs. Even though they can have a "game" mode, which will always be the low latency mode, Sony and Epson projectors have about 25ms of latency, compared to your tvs which could be around 5ms. 

Also consider the speed of sound, which is why even though "professional" products are typically better, like the ATEM with its 1ms of latency, large venues have delay built in by nature of how far away the viewer is from the screen. If someone is sitting 100 feet away, that might be 90ms of audio delay, so reducing delay caused by the digital video is a waste of time since their lips will never match anyway. 

The conductor example is great because someone comparing large arm movements in person with the monitor behind them is super obvious.


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## Gambino (Mar 7, 2020)

macsound said:


> Projectors will generally have a far higher latency than tvs. Even though they can have a "game" mode, which will always be the low latency mode, Sony and Epson projectors have about 25ms of latency, compared to your tvs which could be around 5ms.
> 
> Also consider the speed of sound, which is why even though "professional" products are typically better, like the ATEM with its 1ms of latency, large venues have delay built in by nature of how far away the viewer is from the screen. If someone is sitting 100 feet away, that might be 90ms of audio delay, so reducing delay caused by the digital video is a waste of time since their lips will never match anyway.
> 
> The conductor example is great because someone comparing large arm movements in person with the monitor behind them is super obvious.


The actors will be miced (is that how its spelled?! I’m thinking about mice now) so my main concern will be syncing the audio with video. But definitely latency is still an issue. Do you think that pro projectors with SDI IN will cause a lot of latency still?


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## FMEng (Mar 8, 2020)

Is there an SDI to HDMI conversion going on to drive the TV? That would add latency on top of the others in the system. Also, run the entire system at the TV or projector's native resolution and frame rate Any down conversion will add latency.


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## Gambino (Mar 9, 2020)

FMEng said:


> Is there an SDI to HDMI conversion going on to drive the TV? That would add latency on top of the others in the system. Also, run the entire system at the TV or projector's native resolution and frame rate Any down conversion will add latency.


Now that we're rehearsing with Flat screen tv I'm running a good quality SDI to HDMI converter, but on the actual show It'll be SDI directly from my video switcher to the projector. The projector native resolution is 1920x1200 and I can only work on native video resolutions, so I'm working in 1080i signal. Don't know if there is a significant downconversion/latency issue with such a small difference in pixels. What do you guys think?


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## macsound (Mar 9, 2020)

How does the latency feel now with the TV? I presume the reduced latency of the tv vs projector, plus the added latency of the sdi->HDMI would be about the same as the inherent latency of the projector.

1920x1200 is unfortunately not a native video resolution, its a native computer resolution.
Good news though, the projector doesn't scale 1920x1080 to 1920x1200, it just has 60 pixels of black on the top and bottom.

Did you say your switcher is a black magic ATEM? Or did I imagine that part?


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## Gambino (Mar 9, 2020)

macsound said:


> How does the latency feel now with the TV? I presume the reduced latency of the tv vs projector, plus the added latency of the sdi->HDMI would be about the same as the inherent latency of the projector.
> 
> 1920x1200 is unfortunately not a native video resolution, its a native computer resolution.
> Good news though, the projector doesn't scale 1920x1080 to 1920x1200, it just has 60 pixels of black on the top and bottom.
> ...


Yes it's a ATEM tv studio HD.
The latency in the TV is HUGE maybe because of this particular tv, but you're saying that the SDI ->HDMI conversion + the TV is about the same as the projetor is making me a liitle (panic) nervous I would assume that a SDI direct to the projetor would have less latency than the set up we're using for rehearsals.
Please say it ain't so!!!
Thanks


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## Calc (Mar 9, 2020)

In the current setup you're describing, the TV is your largest source of latency (unless it's a commercial-grade display). TV's add delay doing 'Motion Smoothing' and gimmicks like that. Turn everything you can off to speed it up, or look for a "Gaming mode," which is marketing-speak to reduce delay.
Projectors usually try to do all the same image processing that the TV's are doing, plus keystoning, digital scaling/shifting, etc. It's good that the projector has SDI in- you'll do away with any conversions. Still, turn off as many features as you can- the less processing the image needs the faster the projector will be able to do it.


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## Gambino (Mar 9, 2020)

Calc said:


> In the current setup you're describing, the TV is your largest source of latency (unless it's a commercial-grade display). TV's add delay doing 'Motion Smoothing' and gimmicks like that. Turn everything you can off to speed it up, or look for a "Gaming mode," which is marketing-speak to reduce delay.
> Projectors usually try to do all the same image processing that the TV's are doing, plus keystoning, digital scaling/shifting, etc. It's good that the projector has SDI in- you'll do away with any conversions. Still, turn off as many features as you can- the less processing the image needs the faster the projector will be able to do it.


Alright! That sounds spot on! I turned that gaming mode on but didn't notice any significant improvement. Sounds like manufacturer bullshit! And for me "motion smoothing" is always off!
Thanks


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## josh88 (Mar 10, 2020)

Gambino said:


> Alright! That sounds spot on! I turned that gaming mode on but didn't notice any significant improvement. Sounds like manufacturer bullshit! And for me "motion smoothing" is always off!
> Thanks


It's not bullshit... per say, but calling gaming mode a solution isn't really true. In my experience it makes a negligible difference, especially when it comes to conducting. It just doesn't help when the video is still a half beat behind.


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## Ancient Engineer (Mar 10, 2020)

There is a very low (~1ms) latency solution that we use here: https://www.teradek.com/collections/bolt-family

We have this in place for the clean range more than the latency, but it is a bonus with a real-time display for the public to watch.

If you went: HDSDI camera (like an inexpensive Marshall) direct to the Teradek Transmitter then Teradek RX direct to the display, you would have about the least delay possible in the transmission system aside from analog.

We don't have need of the 4K variant here and the street cost is a few thousand dollars. The RX has HDSDI and HDMI out on the same timetable.

I have used the 4K rig for monitoring of steadicam systems on set and it is pretty amazing...

Your mileage may vary.


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## macsound (Mar 10, 2020)

I'm not sure how the teradek can somehow induce less latency than SDI over a cable.
Adding components to the signal chain like video switchers and converters will add negligibly more latency, but even a string of converters won't have as much latency as the tv or projector itself and I'm saying projectors inherently have more latency than TVs.


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## Ancient Engineer (Mar 10, 2020)

I agree. For reasons unknown, projectors are pretty awful. Barco's are not as vigorous with the internal processing, but are EXPENSIVE...


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## EdSavoie (Mar 10, 2020)

Gambino said:


> Hey sorry to interrupt! But how much money would cost to have 0 latency? What kind of equipment?



Well, if you dust the cobwebs off some old analog gear, free!

Ignoring the technicality that nothing has true "zero" latency, analog included, a digital system really depends on the weakest link, any one given piece of gear across many price ranges could buffer and / or incur a processing delay that induces more latency as already mentioned. Trial and error, and not commiting to anything expensive without testing it is pretty well.

In theory, a network NDI setup can have latency counted in lines when implemented correctly, but given how framebuffers work, they admit you're generally looking at one frame minimum, which mind you is only 16.7ms at 60 frames per second.

an SDI based setup (no converter boxes, everything outputting to / directly accepting SDI) would be likely to yield good results.

(Dumb question, assuming audio is mixed digitally, or you have a some form of outboard gear that can add delay, could you fudge the mix enough such that the monitors and house mix line up with what is being seen by the actors on screen?)


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## Ancient Engineer (Mar 10, 2020)

It is not a dumb question at all. Perfectly possible... but you end up with a slapback kind of delay to the ears of the performers that is difficult to talk against, much less sing against.

Until we get quantum computers that can violate the laws of physics... we are going to be late.

The trick is to minimize the lateness in the critical paths...


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## MRW Lights (Mar 10, 2020)

Well.... zero latency is going to be relative as mentioned above. However you can certainly come close to making it a negligible drift, but you need the budget that allows for it. A majority of my time is now spent Engineering for Film/TV and the integration of Live Performance to the Screen... but in order to get the least amount of lag, with the highest quality of picture and audio we have a team of 5 full time engineers, plus show crew, plus tv crew with a mountain of Video Servers, Fiber Optics, frame syncs, encoders and decoders. You might look into an NDI solution which is a sort of hybrid signal that lives between SDI and Fiber, but does work for 4k video.... 

It's all about the tools and the budget. You can get darn close enough. For me as long as I live at or below actor response time than it's a part of the production and it will likely work. Good Luck!


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