# One Image/Vid on more than one screen



## TupeloTechie (Jun 26, 2007)

How do you split an image or video from a source such as a dvd or computer to fit more than one screen or projector? I am wanting to know this because I am wanting to use two projectors to display one image, and also switch between dual and single. I do not want to use the dual monitor option on windows.

also, just for fun is it possible to split an image between many different sources? It would be cool to have a bunch of old televisions stacked side by side and on top of each other, like a wall, all different, but still combining to create one image.


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## avkid (Jun 26, 2007)

This type of device is good for the old TV situation.
All you need is one RF modulator for the source, and a bunch of cables for the tv's.
http://worldofcables.com/store/viewItem.asp?idProduct=4887


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## mbenonis (Jun 26, 2007)

RF is definitely one way to do it, but you may see artifacts in the signal. You can also get baseband video splitters which will split a composite signal as many as four ways and amplify it to compensate for the split. You probably shouldn't pay more than $30 for one of these.

BTW, be sure to use quality cable for your video - RG6 50Ω coax or better, especially for runs over 10 ft or so. The best and cheapest way to do this is to buy a reel of coax cable and terminate it yourself with either F or RCA connectors (using an adaptor in the former case). I've used Tri-State Electronic in the past, but there are plenty of other vendors as well with competitive prices.


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## SHARYNF (Jun 26, 2007)

Your title and your posting seem to imply two very different solutions

IF you want to take a single source and have it duplicated on multiple monitors ie the SAME image on each display they you need as indicated in the above posts a distribution amp, I would suggest NOT using RF but look at composite or Svideo. BTW |RG6 for video is 75 ohm NOT 50 ohm (for coax ethernet)

IF on the other hand what you want is the flexibility to split an image across a number of display devices you are looking at a very different solution, typically referred to as VIDEO WALL (you can do a google search and see all the options)
http://www.m-media.com/videowall/index.php

Typically these are for a SINGLE source, multiple display

IF you want to have multiple sources across different options on multiple displays then you are looking at a very high end system/server like you see at concerts these systems are in the 25grand and up

The cheapest way for a simple solution is infact back to the multi output graphics card in the pc Matrox for instance, then you can set up split spanning or multiple windows, creating a huge desktop and assigning it to the various outputs of the card, typically working with a dual output dvi card
http://www.matrox.com/graphics/en/gxm/news/pr/2007/th2go_digital.php

so you have triple head to go, beyond this you can also use a video dj type system http://www.arkaos.net/


Sharyn


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## Footer (Jun 26, 2007)

TupeloTechieKid said:


> How do you split an image or video from a source such as a dvd or computer to fit more than one screen or projector? I am wanting to know this because I am wanting to use two projectors to display one image, and also switch between dual and single. I do not want to use the dual monitor option on windows.
> also, just for fun is it possible to split an image between many different sources? It would be cool to have a bunch of old televisions stacked side by side and on top of each other, like a wall, all different, but still combining to create one image.



I think what he is wanting to do is to take 1 picture and take multiple projectors to produce one image. This is an extremely common thing to do, but it can get very expensive very very fast. Watchout system does this, but it can cost around 10-15 grand for a full system, not including the projectors. The triple head to go is my #1 pick if you need three images. With nvidia cards you can get a 2 projector span very easy. The catalyst system and DL2's do this seamlessly including gradient changes with perfect overlays. Arkaos also does it extremely well. As far at the taking 24 tv's and making one big one, yes that gear does exist, but I have no clue where to get it. I remember best buys all having them years back. 

http://www.controlbooth.com/forums/showthread.php?t=4478&highlight=watchout

edit... well I know where to get it. always keep in mind with video, this stuff isn't cheap.


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## Thomas (Jun 30, 2007)

Everyone stop smoking crack.

You'll need a few scaler/switchers, and depending on which type maybe some VDAs (being VGA splitters) as well.

First, you can get away with doing two different screens with one top-line scaler easily- but you lose the preview option then. Take one projector's feed from the program output and the other's from the preview. We did an awesome function on Tuesday with a Kramer VP727 where we had two 9x12 screens next to each other behind the stage and did panoramic backdrops for titles. Obviously, we needed two laptops running two powerpoint slide shows independently.

Otherwise, and the more hardcore approach, is to run two scaler/switchers into each other- so one's output goes to a projector and to the other scaler, so you can do single images distributed, or two different images. The more different images you have more more scaler/switchers you'll need. Depending on which scaler/switcher you're using, you may need to split before feeding projector and the other scaler/switcher. 
I'll post a block diagram if anyone needs?

If you just want one image get a VDA with however many outputs you need and away you go. I've got a 3-way, 4 way and 8 way. Fun fun fun.

If course, you'll need mountains of VGA. Don't be tempted with composite options. Just say no. And don't think of Y-splits, it's practically impossible to make VGA cable as it is. 

AV is fun stuff. Especially when you get into VJing. Just bought Motion Dive Toyko Console Edition, with MDP-1. Awesome!


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## SHARYNF (Jun 30, 2007)

the stacked scalers can do a basic effect like this but it will be either static or very difficult to alter it on the fly without the audience seeing your moving and selecting, so for a fixed setup typically with two displays it is possible and workable, but for instance why go this route with the graphics cards with dual outputs can accomplish the same thing.

Sharyn


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## Footer (Jun 30, 2007)

SHARYNF said:


> the stacked scalers can do a basic effect like this but it will be either static or very difficult to alter it on the fly without the audience seeing your moving and selecting, so for a fixed setup typically with two displays it is possible and workable, but for instance why go this route with the graphics cards with dual outputs can accomplish the same thing.
> Sharyn



Fully agree. There is software out there to do this MUCH easier then anything else. Also, scalers are not at all cheap.


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## TupeloTechie (Jul 1, 2007)

ok, if I was to use the 2 graphics card idea is there any way to run it so that I can use a third monitor to control what goes on the 2 monitors so that it wont appear to be a computer, might there be some type of software?


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## Footer (Jul 1, 2007)

TupeloTechieKid said:


> ok, if I was to use the 2 graphics card idea is there any way to run it so that I can use a third monitor to control what goes on the 2 monitors so that it wont appear to be a computer, might there be some type of software?



Look for a product called mediashout, it does a preview screen. You will need one card of an NVIDIA flavor for the output to the two projectors and another card for the output to the control monitor. What will your content be? Mediashout works great for still and decent for video.


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## TupeloTechie (Jul 1, 2007)

hmmm, that seems like it will work, now the only problem is the price, any other software thats not as expensive?

Edit: It will be a mix between video and stills


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## SHARYNF (Jul 2, 2007)

You might want to check with someone actually using Mediashout. AFAIK it does NOT support multiple display windows for program, it supports a display and control window.

I'd look around at the various VJ solutions on the low end
http://www.numark.com/nuvj

I am NOT sure if it will support multiple displays, it believe it does NOT but the higher end software product from ArKaos does
http://www.arkaos.net/software/vj_features.php the Midi version sells for about 279 dollars

Here is a link to a discussion
http://vjglitch.tribe.net/thread/4fbfa4ba-2ec7-4812-811f-a40a84889c37

Sharyn


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## TupeloTechie (Jul 2, 2007)

The Arkaos software looks more like what I want, this picture from there site is pretty much what I would like to achieve


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## SHARYNF (Jul 2, 2007)

That would be my recommendation, the interface is a bit odd as you can see from the links for the discussion. They do have a DMX version but it is about 3x the price.

Let us know how you get on with it, pay attention to the graphics card requirements if you want to do some effects

Sharyn


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## Footer (Jul 2, 2007)

SHARYNF said:


> You might want to check with someone actually using Mediashout. AFAIK it does NOT support multiple display windows for program, it supports a display and control window.
> I'd look around at the various VJ solutions on the low end
> http://www.numark.com/nuvj
> I am NOT sure if it will support multiple displays, it believe it does NOT but the higher end software product from ArKaos does
> ...



It does have two different outputs, one for the program out another for control. 
http://www.mediashout.com/about/v3/control.cfm

however, it will not split your display accross multiple projectors. You will need other hardware to do that. Arkaos is a great choice, if you can afford it. If you are trying to get one seamless display, arkaos is your answer, if you can get away with a hard line, go with hardware splitters such as an NVIDIA "dualview" card or the triple head line of products.


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## Oldman (Jul 4, 2007)

Another piece of software that allows previewing the program material is Freepath from Grass Roots Software http://www.freepath.com/. The price is $149.00. I have used a matrix switch with driver amps for choosing a single or multiple program sources on a single or multiple displays in a VGA environment. Thee product I used was for a classsroom situation where there is a desktop computer that the instructor may use but often they prefer to bring in their laptop to use instead. I needed a selector switch to chose the source computer and then a splitter amplifier to driuve the desktop monitor and the video projector located on the ceiling. I selected a 2 X 2 matrix switch made by StarTech which allows you to chose which source goes to each of the display devices. This is the model http://www.startech.com/Product/ItemDetail.aspx?productid=ST222MX&c=US and I believe that I purchased them for somewhat less than the price listed here. The switching is done electronically (which avoids the intermittent operation that the mechanical switches all displayed with some use) and is controlled by a simple pushbutton for each output that steps through source one, source two and no signal while showing the source chosen by LEDs. This approach would let you display the same signal on two screens and very simply switch between two sources for each display.

Oldman.


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## Oldman (Jul 4, 2007)

Another piece of software that allows previewing the program material is Freepath from Grass Roots Software http://www.freepath.com/. The price is $149.00. I have used a matrix switch with driver amps for choosing a single or multiple program sources on a single or multiple displays in a VGA environment. Thee product I used was for a classsroom situation where there is a desktop computer that the instructor may use but often they prefer to bring in their laptop to use instead. I needed a selector switch to chose the source computer and then a splitter amplifier to driuve the desktop monitor and the video projector located on the ceiling. I selected a 2 X 2 matrix switch made by StarTech which allows you to chose which source goes to each of the display devices. This is the model http://www.startech.com/Product/ItemDetail.aspx?productid=ST222MX&c=US and I believe that I purchased them for somewhat less than the price listed here. The switching is done electronically (which avoids the intermittent operation that the mechanical switches all displayed with some use) and is controlled by a simple pushbutton for each output that steps through source one, source two and no signal while showing the source chosen by LEDs. This approach would let you display the same signal on two screens and very simply switch between two sources for each display.

Oldman.


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## SHARYNF (Jul 4, 2007)

The key point needed if I read the request correctly is to be able to take a single image, and spread it across two displays. AFAIK freepath will not do this. It is great for a preview of a presentation, and using a DA for putting the same image on multiple displays but not for the "video wall effect"
Sharyn


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## Footer (Jul 4, 2007)

SHARYNF said:


> The key point needed if I read the request correctly is to be able to take a single image, and spread it across two displays. AFAIK freepath will not do this. It is great for a preview of a presentation, and using a DA for putting the same image on multiple displays but not for the "video wall effect"
> Sharyn



yes, but a 70 dollar video card will do it.


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## TupeloTechie (Jul 29, 2007)

What I am trying to do is project images on a cyc with cheap projectors, Using one image/video to be displayed on the cyc with two projectors carefully aligned and keystoned. 

Will a program such as powerpoint or the open office version of powerpoint spread across the two screens, or can I only asign the slideshow to one output?

Also, any cheap slideshow/presentation programs that work well with video?


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## Footer (Jul 29, 2007)

TupeloTechieKid said:


> What I am trying to do is project images on a cyc with cheap projectors, Using one image/video to be displayed on the cyc with two projectors carefully aligned and keystoned.
> Will a program such as powerpoint or the open office version of powerpoint spread across the two screens, or can I only asign the slideshow to one output?
> Also, any cheap slideshow/presentation programs that work well with video?



Your going to get a hard line enless you get a piece of software/hardware that divides and dithers the image so it can be merged. If you just want a cheap and dirty split, get a cheap nvidia card that has two outputs and set it up to do duelview. Powerpoint 2007 handles video pretty well, keynote does a better job. Otherwise, you question has been answered in the the above posts.


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## museav (Jul 30, 2007)

Using multiple projectors to project one larger image is called edge blending and for it to work correctly the images have to overlap to some degree and quite lterally have the image blend across the two. Some projectors incorporate this capability, but it likely won't be included in cheap projectors. There are also external processors that will provide this functionality as well as it likely being accommodated in some software packages. I would be a little wary of the ability for 'cheap' projectors to provide the image geometry adjustments necessary to truly align the two images.

Otherwise, I agree with teh others that the best approach is probably to use a dual video card and live with whatever compromises and issues exist where the images come together.


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## wadeace (Aug 24, 2008)

i just wanted to have you all keep in mind aspect ratios. that if you were looking to project movies or pictures of people that unless it was edit to be shown on an extra wide screen everyone will look fat in the sense that your keeping the hight the same, but doubling the width. even pictures ppt presentations, and normal text and slides will look this way unless the content was built to be shown that way. there are some articles on the cow that ill find and post a link to about building a project for digital signage, but the principals the same.


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## ruinexplorer (Aug 27, 2008)

Footer4321 said:


> Your going to get a hard line enless you get a piece of software/hardware that divides and dithers the image so it can be merged. If you just want a cheap and dirty split, get a cheap nvidia card that has two outputs and set it up to do duelview. Powerpoint 2007 handles video pretty well, keynote does a better job. Otherwise, you question has been answered in the the above posts.



Also, without edgeblending software (either on the projector end or the source end), where the image overlaps will be brighter than the rest (which can spoil the effect). No matter what, you are going to have to make compromises. Big production companies get the coolest effects because their clients have the money to spend on the gear, that's why you aren't finding a cheaper way to do it the same way.


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