Switching Projectors

Robert F Jarvis

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Joined
Apr 8, 2017
Location
Sebring, FL, USA
We are going to use two projectors for different cycs during a new show. The animation clips are running on a laptop with MS PowerPoint (works a lot better then anticipated) . But we are having a problem finding a 2nd computer to accommodate the 2nd cyc. As we are using the two cycs at different times it would seem that we could merely remove the HDMI from projector 1 and plug in HMDI from projector 2. But I am nervous that the projector being switched out will report "No HDMI" as the scene changes and then switch off.
So, question: How could I use one computer to feed a PowerPoint presentation to two separate projectors at different times during the show?
 

Robert F Jarvis

Well-Known Member
Joined
Apr 8, 2017
Location
Sebring, FL, USA
Hmm! OK. I have never used one. So I could send from one computer out to to two projectors. Question is we don't want to see both projectors at the same time (different scenes/cycs) other wise we'll get splash from the unwanted guy. The other question would be that having switched from one projector to the other we need say a black image with a little none black are in it to keep the unwanted projector 'alive'. Does that make sense? If I had the time I would make some sort of mechanical masks to drop in front of the projector's lens. They could run all the time but we could obstruct the lens of the unused projector.
 

Amiers

Renting to Corporate One Fixture at a Time.
Joined
May 28, 2009
Location
Phoenix, Az
Active HMDI switchers will only show whatever output you select. The 2nd projector will need to be on and you will have to set the native splash to black or as you said get a douser. No switch is going to give you true black.
These amazon switchers are cheap. So it’s one of the get what you buy. From the list go with one that lets you pick the output.
Alternatively you could get yourself some semi prograde gear and get a Roland switcher. https://www.bhphotovideo.com/c/prod...6h2vivxZAGS1CwaAq8tEALw_wcB&lsft=BI:514&smp=y

Just comes down to what you want to spend and how comfortable you are trying new things. You could hire someone that does this kind of work and then you don’t need to worry about anything but 🤷🏻‍♀️
 
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dbaxter

Well-Known Member
Joined
Mar 10, 2007
Location
Rochester, NY
Something like this USB to video would give you an output for the second projector. You could run two instances of PowerPoint, one for each. CP Plus does control two video outputs directly.
And, yes, there are commercial dousers. I made mine, however, from a radio controlled car servo and a usb interface from Phidget. There's a video on my YouTube.
 
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Robert F Jarvis

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Joined
Apr 8, 2017
Location
Sebring, FL, USA
That's interesting and a lot better than the prices I saw. My problems looping and fading in SCS disappeared when I updated the version on my computer. It can also send each cue to 1 of 4 'screens' (Projectors) though the old question about the keeping the dormant projector alive remains. It will probably be less expensive to run SCS on two computers and intersperse the images with "Black" slides. I put a tiny little purple circle at the bottom which is enough to keep the projector alive.
 

ruinexplorer

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If you have dousers, you could always send the same signal to both projectors and then have the douser blocking the one you don't want used. Fade through black to give the douser the time to close/open.
 

Robert F Jarvis

Well-Known Member
Joined
Apr 8, 2017
Location
Sebring, FL, USA
Not quite right in the case of some projectors. Both our Optoma and ViewSonic seeing a 'black' picture/slide think that means "No signal" and after about 10 minutes turn themselves off. Black means no lamp illumination. Inconvenient to say the least. However, by putting a really, very small circle or square in a bottom corner and coloring it say dark purple so it is not noticeable then the projectors see the none black pixels and stay alive forever!
 

jtweigandt

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Joined
Aug 2, 2013
Location
Moline Il
I've had a couple viewsonics that time out if the picture doesn't change for a period of like 10 minutes... then up comes the bird splash screen.
So moving from one black screen to the next black screen slide seemed to keep them unobtrusively alive and ready for the real projection.
 

almorton

Well-Known Member
Joined
Dec 17, 2014
Location
Caterham, Surrey, UK
Ah, OK. Our NEC doesn't suffer from either of those problems. As long as it has a signal (even a completely black screen), it stays locked to it. We've had shows where there were long periods of no projection, and it wasn't a problem.