QLab on 8 screens.

tirnion

Member
Hello, everyone. I'm hoping you can help me figure out how to run a projection rig.

I have done projections several times before, but never on this scale. The director and scenic designer have asked for one projector and seven television screens, all running different video through the show. Unfortunately, the company does not have nearly enough money to rent a couple of Hippos, so we are looking for a different solution.

I am thinking of suggesting a Mac Pro running QLab, maxed out on video cards, with a USB- to VGA device for the monitor. We would also put at least 10GB ram in it, as well as have 7 PC to Video adaptors to convert DVI or VGA signal to Coax for the television screens. Does this sound like a reasonable setup, or am I completely out of my mind? I would welcome any suggestions you might have.

TL;DR version: Mac Pro running Qlab with 10GB RAM and 4 video cards (+ 1 USB to video for a monitor) + 7 PC to Video convertors (VGA to Coax) + 1 projector. Crazy?
 
Hello, everyone. I'm hoping you can help me figure out how to run a projection rig.

I have done projections several times before, but never on this scale. The director and scenic designer have asked for one projector and seven television screens, all running different video through the show. Unfortunately, the company does not have nearly enough money to rent a couple of Hippos, so we are looking for a different solution.

I am thinking of suggesting a Mac Pro running QLab, maxed out on video cards, with a USB- to VGA device for the monitor. We would also put at least 10GB ram in it, as well as have 7 PC to Video adaptors to convert DVI or VGA signal to Coax for the television screens. Does this sound like a reasonable setup, or am I completely out of my mind? I would welcome any suggestions you might have.

TL;DR version: Mac Pro running Qlab with 10GB RAM and 4 video cards (+ 1 USB to video for a monitor) + 7 PC to Video convertors (VGA to Coax) + 1 projector. Crazy?

[-]I'm not so sure that the mac pro can handle 10 GB of ram.. [/-]Most i know of for a "consumer" grade PC is going to be 8 gigs and thats for a 64 bit system. 32 bit your stuck at 4 gigs. Why not use two separate macs?

(after some research, they can handle up to 16 gigs of ram due to the 256 bit architecture.)

Still though it seems a better use of budget to use two macs linked together for the video since it would cost you about $5700 (from apple) to get max ram in the system.

Since I'm not used to QLab (never used it) How many outputs does it support?
 
[-]I'm not so sure that the mac pro can handle 10 GB of ram.. [/-]Most i know of for a "consumer" grade PC is going to be 8 gigs and thats for a 64 bit system. 32 bit your stuck at 4 gigs. Why not use two separate macs?

(after some research, they can handle up to 16 gigs of ram due to the 256 bit architecture.)

Still though it seems a better use of budget to use two macs linked together for the video since it would cost you about $5700 (from apple) to get max ram in the system.

Since I'm not used to QLab (never used it) How many outputs does it support?

It supports showing video on exactly 8 screens. I'm not sure where you got this 16gb limit/256 bit processor idea, though, windows 7 x64 can handle 192gb of RAM (how you'd fit it in there I'm not sure) and the apple site suggests that 32gb, the most you could fit in 4 DIMM slots easily, is supported by Mac OS.

As for economy, the cheapest way would be to buy the box with the right processor but all other specs at minimum, then upgrade it after the fact without paying the Apple 300% markup on what are commodity components.
 
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It supports showing video on exactly 8 screens. I'm not sure where you got this 16gb limit/256 bit processor idea, though, windows 7 x64 can handle 192gb of RAM (how you'd fit it in there I'm not sure) and the apple site suggests that 32gb, the most you could fit in 4 DIMM slots easily, is supported by Mac OS.

Where are you getting the data for Windows? I was pretty sure it was limited to 8.

Sent from my ADR6300 using Tapatalk
 
And I'm running 24gb in a machine right now.

In this case I think disk access speed would be more important than RAM, depending on how long your videos are, what resolution they are, and how many are playing at once. QLab will preload the start of a video into RAM before it begins to play (so it starts exactly when you want it), but once it starts the rest of the system has to keep up.
 
Before I stopped using QLab for video work, I did this type of thing a few times. I ran a 12 screen show once using 7 Mac Minis (6 driving two outputs each plus one for the op that triggered the others). I would tend to think that multiple computers running a few outputs each is going to be better but you do need to rent or buy additional licenses then. Your proposed Mac Pro setup should work though as long as you have suitable graphics cards.
 
Also, you would do well to ask this question on the QLab email group as you will get lots of answers from pretty die hard QLabers and often the creator himself.
 
I would get something like this although it does cost $1,800...

And Metti is correct, the QLab listserv is a great place to ask questions. You can find it here
 
This ought to work. Make sure your graphics cards are high enough ended to run video all the time, the ones we have tend to lag if there is video through all of them. Your setup looks reasonable, and I have run a similar one to that which you propose. Just make sure you have enough graphics RAM to keep lag out of the system.
 
I would get something like this although it does cost $1,800..

You definitely do NOT want something like that. That card is specifically designed for data type multi display applications. You will not get the kind of performance for video that you need from those types of cards since they are targeted at an entirely different type of user (financial, transportation, industrial monitoring, etc) and not high performance graphics processing like you need. You would be better off getting a couple higher performance video gaming type cards with tons of VRAM.
 
You definitely do NOT want something like that. That card is specifically designed for data type multi display applications. You will not get the kind of performance for video that you need from those types of cards since they are targeted at an entirely different type of user (financial, transportation, industrial monitoring, etc) and not high performance graphics processing like you need. You would be better off getting a couple higher performance video gaming type cards with tons of VRAM.

I wouldnt be supprised if all it did was treat the aray of 16 monitors as one display in terms of resolution and whatnot. It looks like its for stockbrokers and dispatch centers and command centers of various types, not for a ton of video. Just get 4x 2 output DVI cards with a minimum of 1GB vram on board. Actually, that and a very fast reading hard drive are more important than a ton of RAM sticks.
 
Actually, that and a very fast reading hard drive are more important than a ton of RAM sticks.

You're mostly right. Fast HDs and a lot of VRAM are both really important but so is regular RAM with QLab since it uses it to help start cues immediately upon Go. I would see if you can swing the cost of SSDs for your drives. I just finished building a new 6 output video computer to run Isadora. It has a 128GB system SSD, a 256GB project SSD, and a 2TB 7200RPM drive for storing files that aren't in use on a particular show. Running a show entirely from the two SSDs is proving to provide pretty fantastic performance and it didn't cost an extraordinarily large amount of money compared to what an array of 7200RPM drives would have.
 
As a point of discussion, since the OP has not yet speced a system, does anyone have other suggestions besides Qlab that could accomplish his goals at relatively the same budget (this could also be pulled off into a separate discussion)?

tirnion, maybe you could describe a bit more about the different content that will be displayed on the various monitors an projector so that additional ideas can be discussed. Also, what are the various resolutions of the displays that you are using? Are all the monitors the same resolution or a mixture?
 
As a point of discussion, since the OP has not yet speced a system, does anyone have other suggestions besides Qlab that could accomplish his goals at relatively the same budget (this could also be pulled off into a separate discussion)

Ahhh...if other software is on the table then this discussion changes pretty drastically. My first gut reaction would be to say rent a Watchout system but given the high number of outputs you are looking for, Watchout probably isn't going to be cost effective. Part of it comes down to renting versus buying, a decision that is largely dependent on the type of show and how long it is expected to run, and one that none of us can really decide for you. My current projection design software du jour is either Watchout for shows that are dependent on heavy timeline work and/or mapping that involves complex 3D projection surface or Isadora for everything else. Isadora permits up to 6 video outputs per application instance so you would need to computers running the software but Izzy is also pretty inexpensive and, depending on what you're doing, the hardware might not be so expensive either so it may end up being significantly cheaper and will definitely be more powerful then QLab. Isadora is nice in that it is extremely efficient for simpler stuff and, for more complex work, you have your choice of a CPU processing heavy system or you can use the Core Edition on Macs to offload processing to the graphics card. Isadora also has really nice support for the Matrox Double and TripleHead2Go line which can come in handy for certain applications. The one biggest thing to consider with Izzy is that it is really more of a blank slate then some of these other programs. I am able to work pretty efficiently because I have spent to last couple years building up an extensive selection of plugins and user actors that allow me to make it do what I want without starting from scratch on every show. If you do end up wanting to check out Izzy you can grab many of these tools as a free download from my website.
 
Ahhh...if other software is on the table then this discussion changes pretty drastically. My first gut reaction would be to say rent a Watchout system but given the high number of outputs you are looking for, Watchout probably isn't going to be cost effective. Part of it comes down to renting versus buying, a decision that is largely dependent on the type of show and how long it is expected to run, and one that none of us can really decide for you. My current projection design software du jour is either Watchout for shows that are dependent on heavy timeline work and/or mapping that involves complex 3D projection surface or Isadora for everything else. Isadora permits up to 6 video outputs per application instance so you would need to computers running the software but Izzy is also pretty inexpensive and, depending on what you're doing, the hardware might not be so expensive either so it may end up being significantly cheaper and will definitely be more powerful then QLab. Isadora is nice in that it is extremely efficient for simpler stuff and, for more complex work, you have your choice of a CPU processing heavy system or you can use the Core Edition on Macs to offload processing to the graphics card. Isadora also has really nice support for the Matrox Double and TripleHead2Go line which can come in handy for certain applications. The one biggest thing to consider with Izzy is that it is really more of a blank slate then some of these other programs. I am able to work pretty efficiently because I have spent to last couple years building up an extensive selection of plugins and user actors that allow me to make it do what I want without starting from scratch on every show. If you do end up wanting to check out Izzy you can grab many of these tools as a free download from my website.

I would definately not reccomend Isadora for a begining user, I had 3 people with me trying to figure it out and we hammered at it for a week before we gave up and started using cue lab. Its so extremely flexible that it takes some time to learn, and for simple, cue lab is my choice. If someone was able to sit down and teach me izzie, I would probably want to use it, but We were just unable to make it do what we wanted it to do in a reasonable amount of time.
 
I would definately not reccomend Isadora for a begining user, I had 3 people with me trying to figure it out and we hammered at it for a week before we gave up and started using cue lab. Its so extremely flexible that it takes some time to learn, and for simple, cue lab is my choice. If someone was able to sit down and teach me izzie, I would probably want to use it, but We were just unable to make it do what we wanted it to do in a reasonable amount of time.

I completely agree that Isadora isn't the best choice for someone who has never worked with these types of programs before but the OP was offering QLab as an alternative to a Hippotizer which also has something of a learning curve. Yes, QLab is really easy to use but its video capabilities are, ultimately, pretty simplistic and not very powerful unless you are willing to start using Quartz Composer, which is somewhat more difficult than Isadora and definitely brings us back to a not-for-beginners place. If you were in Boston or NYC I would offer to give you an Izzy 101 but, alas, you are not. That offer does extend to anyone else who is interested though. In the end though, Isadora really isn't all that complicated once you get the basic hang of how you need to think to make it do what you want.
 
I completely agree that Isadora isn't the best choice for someone who has never worked with these types of programs before but the OP was offering QLab as an alternative to a Hippotizer which also has something of a learning curve. Yes, QLab is really easy to use but its video capabilities are, ultimately, pretty simplistic and not very powerful unless you are willing to start using Quartz Composer, which is somewhat more difficult than Isadora and definitely brings us back to a not-for-beginners place. If you were in Boston or NYC I would offer to give you an Izzy 101 but, alas, you are not. That offer does extend to anyone else who is interested though. In the end though, Isadora really isn't all that complicated once you get the basic hang of how you need to think to make it do what you want.

This is true, I had missed the hippotizer bit. Who knows, maybe ill come visit boston for unrelated business, I would love to figure out how it works, we own a licence for it but I cant figure out how to use it right...
 
Who knows, maybe ill come visit boston for unrelated business, I would love to figure out how it works, we own a licence for it but I cant figure out how to use it right...
I'm often in Manhattan as well so I can meet there. Anyway, if you end up in either and you want an intro to Izzy, you know how to reach me.
 
Christopher Ashworth said:
I'd just add that 8 streams is going to be pushing your hardware VERY hard. You'll need a monster machine to make it work, and probably not use high resolution video.

It may be more feasible to do it with a few independent machines all playing back at the same time. For example 2 driving 4 displays each.

And

Dominic said:
I have literally just completed a project like this running 5 video sources from a single Mac Pro.

I used 2 dual head graphics cards which then spilt as follows:

1) Local Operator (Res 1600x1200)
2) TV output 1 (Res 800x600) then through scaler to composite
3) Matrox Triple Head (Res 2400x600)
4) TV output 2 (Res 800x600) then through scaler to composite

We opted for 800 x 600 as the source content was bounced down to standard PAL definition. The images being presented on CRT TV's meant that this resolution was more than adequate and lowered our overheads on the graphics cards and internal buses.

Multiple slave machines with a master sending MIDI commands is your best bet.
 

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