Qlab - Projector 'Blackout'?

someckguy

Member
Hi, I've very recently started using Qlab, and currently I use a blank white or black image to 'black out' the projector when I don't have a video/projection up, but this is very impractical and creates more to do. Is there an easier feature within qlab? I don't currently have access to a theatre so I use an external monitor to act as the projector for learning qlab, but when I don't have any image or video cues running, it shows my desktop (which is why I use a blank image). I'd like to change this so that it actually shows just white, or preferably nothing at all.

Sorry if the question is a bit confusing. Additionally, I am only running the free version of qlab.
 
I don't know if there is a way to set up Qlab to default to that. I'm recalling reading something where the guys at Figure 53 recommend making your desktop black anyway.

Alternatively you could always build or buy a projector dowser. Even when black screened, your projector will continue to output a reasonable amount of light which will be obvious during a blackout.

Here's the document I was thinking of- http://figure53.com/notes/2013-10-29-prepare-execute-troubleshoot/ I skimmed but didn't see anything about the desktop background.
 
I don't know if there is a way to set up Qlab to default to that. I'm recalling reading something where the guys at Figure 53 recommend making your desktop black anyway.

Alternatively you could always build or buy a projector dowser. Even when black screened, your projector will continue to output a reasonable amount of light which will be obvious during a blackout.

Here's the document I was thinking of- http://figure53.com/notes/2013-10-29-prepare-execute-troubleshoot/ I skimmed but didn't see anything about the desktop background.
Thanks for your reply. Unfortunately if I black out my desktop my toolbar at the top still appears. And the projector is hanging on the roof above the center of the stage behind a divider, and projects on a screen on the cyclorama, so I can't access it physically.
 
If you set up the projector as a second monitor, then you can set that desktop as black and then you can avoid toolbars and still retain your desktop image/all the files on it. We always keep the desktop image to the logo of our theater/whatever act has come through just in case. Admittedly, it has saved my careless ass a couple times.
 
Qlab has an option in the "tools" menu to also "Black out" desktop, and "restore desktop"..... I think this might be what you are looking for.

[EDIT] In addition and like Petercav17 said, if we have a group or sometimes the school doing something, I will set a Jpeg of the group/show/venue logo or black as my "whoopsie' background, depending on what makes most sense.

Black JPG is easy. Create an Powerpoint file, take your master slide, set to black. One of the save options for Powerpoint is to save/export each slide as an image (jpeg), and your got your black image to use. Because annoyingly enough you can't choose "black desktop" from any of hte Mac OS default sources :p

[Edit 2] Many projectors in the last 5 years all have a Shutter, or Blank out, function. Mostly because turning projectors off and on is not great for lamp life if you just need the projector "off" for a short time.
 
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If you set up the projector as a second monitor, then you can set that desktop as black and then you can avoid toolbars and still retain your desktop image/all the files on it. We always keep the desktop image to the logo of our theater/whatever act has come through just in case. Admittedly, it has saved my careless ass a couple times.
The problem is, I have my monitor set up the same way the projector will be set up, as a secondary display, but since I'm running OS X Yosemite, the toolbar is always there, even on an extended display. That's the problem.
 
This was what Google came back with. I pulled out an answer that seemed to fit what you needed. Should solve your toolbar/ menu problem.

https://discussions.apple.com/thread/6635429


This gets a bit involved. The "each screen has its own space" option in the mission control control panel is turned on by default in Yosemite. (I don't know about earlier versions). Turning it off will remove the second menubar after reboot. I tried this before but I think I didn't notice the little blurb about having to log out to make the changes. At this point, if you only have one user login, the menu issue is resolved. But if you have multiple users, as I do, you need to go to each user and turn off the "each screen has its own space" option for all of them. Otherwise you can develop really strange issues. If I have the option turned on in some users and turned off in others every time you switch users the Mac will lose all its display settings background, screensaver, etc. This problem may be specific to my late 2009 Mac Pro.
If you're using the multiple screens with the "each screen has its own space" option turned on and want to prevent the dock from leaping from screen to screen you can pin the dock the right or left side. That seems to keep it in place, even if it's not the precise place where you'd like it kept. I have yet to see the dock change screen with the "each screen has its own space" option turned off. I doubt it will.
So for me it seems that turning off the "each screen has its own space" option in the mission control control panel for all user accounts and rebooting resolves my issues. Your results may vary.
 
This was what Google came back with. I pulled out an answer that seemed to fit what you needed. Should solve your toolbar/ menu problem.

https://discussions.apple.com/thread/6635429


This gets a bit involved. The "each screen has its own space" option in the mission control control panel is turned on by default in Yosemite. (I don't know about earlier versions). Turning it off will remove the second menubar after reboot. I tried this before but I think I didn't notice the little blurb about having to log out to make the changes. At this point, if you only have one user login, the menu issue is resolved. But if you have multiple users, as I do, you need to go to each user and turn off the "each screen has its own space" option for all of them. Otherwise you can develop really strange issues. If I have the option turned on in some users and turned off in others every time you switch users the Mac will lose all its display settings background, screensaver, etc. This problem may be specific to my late 2009 Mac Pro.
If you're using the multiple screens with the "each screen has its own space" option turned on and want to prevent the dock from leaping from screen to screen you can pin the dock the right or left side. That seems to keep it in place, even if it's not the precise place where you'd like it kept. I have yet to see the dock change screen with the "each screen has its own space" option turned off. I doubt it will.
So for me it seems that turning off the "each screen has its own space" option in the mission control control panel for all user accounts and rebooting resolves my issues. Your results may vary.
I'll play with these settings next time I have qlab open. Thank you so much!
 
This isn't qlab related. It is all in the OS.
 
This computer setup checklist covers all of the above and may be helpful.
 

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This computer setup checklist covers all of the above and may be helpful.

Wow, thank you so much man. Quick question, do I necessarily need an external sound card? I was planning on just connecting the laptop to the desk using an aux-xlr cable or similar (which is how other people have ran small shows from that theatre in the past, not sure how it's set up, as I don't have theatre access).

A little bit of background for those interested,it's a small musical run in a tiny theatre, since we can't afford to hire the main hall. I'm actually head tech, and am assigned to lighting, but my role is also to help out my "team" which consists of a sound operator and a followspot operator. We're going to go into the theatre for the first tech rehearsal in about 3 weeks, which we are doing unconventionally, as we are going to do multiple runs through and are going to be programming "on the fly". We start performances in 8 weeks but its valuable to have physical access to start bringing everything together.
 
Well, this response is coming a bit late, but may be valuable nonetheless. As far as I'm concerned, yes, you need an external sound card, also called an audio interface. Because:

1. Your audio quality will be better, sometimes significantly better, than outputting from the headphone jack.
2. You can't accidentally play system sounds through the sound system because only QLab, and not OS X itself, can access the card (assuming your system prefs are set right).
3. The system volume on the computer is irrelevant. You can set the computer to silent to avoid unwanted sounds and QLab's levels will be fine.
4. An external sound card allows you to do things like use Mic cues in QLab (without aggregate devices).
5. Those 1/8 in to dual 1/4 cables that people use to connect their laptops to consoles are often very badly made and will flake out on you and make terrible noises. An audio interface is much more reliable.

And, the most fun reason:

6. You need an interface if you ever want to output more than two channels. Which sound designers usually do.

Hope this helps!
 
Back to the topic of blacking out your screen...

I generally make a black jpeg in photoshop and have it as the first cue on my cue list, play it as soon as I turn the projector on and leave it playing; all your other projection material will just go over the top and once they finish it will simply return to black. Just ensure that it is on the bottom layer in the display and geometry tab.

Only issue I have with this method is using the panic button fades it out...
 

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