# Need help with architectural video installation



## bbigelow666666 (Feb 10, 2012)

Greetings, 

I'm a newbie to this forum...it looks like a great place with some like minded folk! I'm planning to do a projection on a large wall outside and need some help getting started in my research. Thanks a bunch in advance!

I need advice on what kind of projector to use and the appropriate video hardware and software necessary. But first...

*Site information:*

-The wall I'm projecting on is: 1249"W x 184" H. 104ft by 14 ft.
-Where I'm planning on installing the projectors is a 96 foot throw distance from wall to lens. The projector location would also be approximately 19 feet high (installed on a roof of an opposing building).
-I will be projecting at night, and there is a moderate amount of ambient light (is there a way to accurately measure this if necessary?). And a streetlight makes the right side of the building brighter. This does not worry me too much, as I might either block that light or incorporate it into the design of the video content. Still, it should be noted that the ambient light across the wall is not consistent.


*Projectors?*

From my research thus far it seems I need to use multiple projectors with edge blend them. Using 4 projectors with 16x9 aspect ratio, the vertical of the video would fit the vertical of the wall with appropriate overlap. (Image attached). In this scenario each projector would be throwing a 375" diagonal. (note: If you look at my image you can see the overlap I anticipated...is that about how much overlap is typically required for edge blending?)

However I think using 4 projectors is going to become too complicated, and I'm thinking of limiting it to 3. In this case each projector would need to throw a 500' diagonal. The image projected would be letterboxed, and I would loose about 33% resolution, which is OK with me. Image attached.

(note: I mocked this up by using after effects to create a composition of my wall in pixels to inches)

So what kind of projector do I need? Is there a projector calculator out there that works backwards? (Meaning I input the throw distance and screen size and it suggests an appropriate projector)

The question some may be wondering now is "what is this dude's budget?". As of now, I'm hoping to get these projectors loaned to me for free by a company. I'm a graduate student at a university that I'm hoping has some good technology hookups in the A/V world. So far, companies that I think I might have an in with are Panasonic, Epson and Optoma...but open to other suggestions. I'm in Palo Alto CA if anyone knows other projector manufacturers out here.

So I need something high lumen and with a lens capable of that throw distance. Also lens shift seems crucial to install it.

_(sorry this is so long! but more always seems to be better than less in these forums)_

*Video Hardware:

*For the video hardware and software I was planning on purchasing it myself and spending around $2,000-3,000. Is that appropriate? If there is a solution that is much more expensive I would still like to hear it, maybe the university can pull some strings. But I would prefer to avoid this and purchase within my budget.

I've never done work with edge blending projections. One thing I'm confused by overall: do the projectors need to have edge blending technology or is this something projection software on the computer can do? Or does both my computer software AND projector need to have edge blending technology?

The computer I will most likely have access to run the video is a Mac Pro. I don't have the exact specs on me, but I believe it's a quad core with 8gigs ram. Not sure of the graphics card, but I can get more info if necessary.

So one option for hardware I saw was this Matrox device: Matrox Graphics - Products - Graphics Cards - M-Series - M9138 LP PCIe x16

However it seems this ^ is only for PC?

Matrox also offers this: Multi Monitor Adapter for Maximum Performance | TripleHead2Go

But this ^ sounds dubious because it's using the existing GPU to render the graphics (I'm assuming the former Matrox product helps with added video RAM?). From my calculations, using 3 projectors at full HD (minus the 33% from letter box) I have to output a 5760x720 image. Is this even possible? Do I need to split up the projection onto multiple computers? If that high of a resolution becomes impossible, maybe I should use 720p projectors? This would also make creating the graphics easier too. (I will be creating the content on Aftereffects CS 5, which I know doesn't like big resolutions). But man do I like the look of big resolutions!

If a application for the PC platform is much easier, I may be able to acquire a PC for this project. However, I would prefer to stay Mac. 
_
(my brain is really hurting, sorry if yours is too!)


_*Finally, what projection software do I need? 

*-Seems like I need video software that supports edge blending (unless the projectors take care of this?). 
-I will also need something that allows for masking and projection mapping. The wall I'm projecting on actually slopes along the bottom with a difference of 10" on either side, so I'll need to adjust the image to fit the wall on site.
-I'm planning on having this running every night for a month. Would be great if the software could start and stop the projection at certain times. However I could automate this with other controlling software, I believe, so it's not a deal breaker.
-Again, I will be running OS X, unless a PC solution is preferred. 

I've looked at Qlab, Isadora, Dataon and Green hippo, but it's all very confusing to me.

I think that's it.

Hopefully this wasn't to wordy. THANK YOU SO MUCH in advance for any advice you may have. 

Best, 
Ben

IMAGES:

(3 projector example)
View attachment 6266



(4 projector example)
View attachment 6265


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## museav (Feb 10, 2012)

Several aspects to address...

A 10% to 15% overlap is pretty typical for edge blending.

You could measure the ambient light levels and that would be the optimal approach but will the situation realistically be more that of taking what you can get as far as projectors.

There are various hardware and software options. Some projectors directly support edge blending or there are dedicated video processors that support edge blending. Some software will handle the edge bending on the source machine(s) if used with appropriate video cards. The edge blending itself need only be addressed in one place, however that may require having an appropriate image to start with. One factor in this may be whether you would always have one image or if you may want to have multiple images or windows and if those are then static or dynamic. Capabilities such as image warping may also be factors in what approach works best for the application.

The Matrox TripleHead2Go is essentially making three displays appear to the computer as one large display. It is also limited in the resolutions supported, not only do all three displays have to have the same resolution but there is a somewhat limited list of supported resolutions. In other words, a good option for some situations but not necessarily a good option for edge blending.

What type of environment would the projectors experience? This is outdoors and if the projectors are also outdoors for a month then that means environmental enclosures, especially if you are going to borrow or rent the projectors. Probably some significant power draw as well. The there's getting the signal from the source to all of the projectors as well as any control if you want to remote control their power function.

This also starts to get into the practical considerations. You seem to be assuming having companies donating much of equipment but I would confirm that and what is possible before going too far. Projector manufacturers probably have numerous requests for 'donating' the use of their projectors and a month plus is a long time, so what makes this use special? I can also see them wanting to see some evidence of a proper plan or even a sample of the video as it is reasonable that they would want the result to be something that provides a positive impression of their products. They may also want some recognition, so consider whether something like "Projectors provided by XYZ" signage would be possible. And keep in mind that manufacturers may not want to cut out their local dealers and users. And even if the projectors were donated, there will probably still be cabling and signal distribution, power, possibly projector housings, etc. to address. And you'd probably want some spare lamps as those may not be donated with the projectors (if the projectors are multiple lamp models you may even want to consider running them off half the lamps so if a lamp does fail you could switch to the other lamp(s) rather than having to stop and replace lamps).


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## bbigelow666666 (Feb 10, 2012)

Thanks for your help, Brad!

Some responses...

Edge blending:

The image I'm projecting needs to be seamless across all three projectors, and the imagery is dynamic across the entire projection. I will not be needing separate windows. 

I believe I need image warping, is this the same as projection mapping? Basically what I need to do is make minor adjustments on the edges of the entire image to fit inside the building. But it's a flat surface, not a sphere or anything like that.

I guess edge blending on the projectors itself would be the least processing intensive way to go if I can get them. For example, in a projectors such as these: Pro Z Large Room Installation Projectors, software is then not necessary to do the edge blending?

If I cannot get edge blending projectors, then from my understanding the software needs to do this. One solution I've been researching is Triple Head to Go with Resolume 4 Arena. From the Arena forums, my research suggests that edge blending with 3 projectors is possible here...

As you said though the resolutions are limiting. Using OS X I'm limited to 4080x768. That starts to get really low considering my image will be cropped another 33% resolution from the height.

However using a PC I can hit my target resolution of 5760x1080.

The nice thing about the above solution is the price. The Triple head to go is around $350, and with a student rate I can get Resolume 4 Arena for $460. But again, I would have to go PC, which is a bummer (but not necessarily a deal breaker).

Is there a solution in a similar price range, or at most around 2-3 grand for OS X? 

One thing that still concerns me is buffering a 5760x1080 or even 4080x768 video file from the computer. I still have to get the specs on my available computers, however in your experience what is the minimum requirements for a graphics card/processing power? I will not need to mix the video or apply any real-time FX, it will just be looping.


Yeah I hear you on the installation in an outdoor environment. It's part of my considerations, but right now I'm first trying to get a sense of the technology necessary. And most definitely, when I approach the companies, I will have a detailed plan discussing my project and the benefits etc you mention.

THANK YOU!


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## bbigelow666666 (Feb 11, 2012)

I'm thinking I might try and do this with 2 projectors instead. This way I could just use the 2 DVI out ports already in the Mac Pro's video card. I could also use one of the Matrox products to have a control screen. And loaning/installing 2 projectors is more manageable. However this makes a diagonal of 650" which I need to found out if it's possible. With a 96ft throw distance it should be though...

Also this helps because I can then reduce the resolution of my content, which will really save me in editing. The new comp would be 540x3072, which turns out to be less pixels than a 1920x1080 frame, which After Effects will thank me for.

But would still love to hear solutions for 3 projectors too.

Thanks!


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## museav (Feb 12, 2012)

bbigelow666666 said:


> I'm thinking I might try and do this with 2 projectors instead. This way I could just use the 2 DVI out ports already in the Mac Pro's video card. I could also use one of the Matrox products to have a control screen. And loaning/installing 2 projectors is more manageable. However this makes a diagonal of 650" which I need to found out if it's possible. With a 96ft throw distance it should be though...
> 
> Also this helps because I can then reduce the resolution of my content, which will really save me in editing. The new comp would be 540x3072, which turns out to be less pixels than a 1920x1080 frame, which After Effects will thank me for.
> 
> But would still love to hear solutions for 3 projectors too.


Your projectors will be whatever resolution and format they are. For example, if you had two 1024x768 native resolution projectors with a 10% overlap for edge blending then the total image resolution would be 1946x768, that is what would be displayed and anything else sent to the projectors, assuming it were a compatible signal, would be scaled to that. For your image you would then use only a portion of the overall vertical image and for a 104'x14' image that would equate to a 1946x262 resolution.

Also think of how that affects the image each projector actually creates. For a 104' wide overall image with 10% overlap then each 1024x768 projector would need to create a 656.84" or 54.74' wide image, with which the 4:3 format of the projector relates to a 492.63" or 41.05' image height. That's a 821.05" or 68.42' diagonal image and even at night probably relating to needing 20,000+ lumens.

So for a 104'x14' image with two, edge blended, 1024x768 projectors you would have two 54.74'x41.05' images with a total resolution of 1946x768, of which the portion related to the building would be 1946x262.

With the 104'x14' image you desire, then widescreen projectors and/or a larger number of projectors could increase both the usable resolution and the percentage of the overall image that is actually used. But this is why it is important to know what you plan or can use for the projectors as their native resolution drives both the usable resolution and the overall image size.

As far as throw distance, you are talking about being in the range where the projector may not even have a standard lens and you select the lens to fit the application. That's great if you were purchasing but makes it difficult to predict for rental or loaner equipment as you have to know what lenses are being provided with the projectors.


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## SHARYNF (Feb 13, 2012)

The chances of getting anyone to lend you 2 or 3 20k lumen projectors to put outside for a month is probably very very unlikely. Each projector is about a hundred grand without any special lens. Is it possible for you project to scale back the size and the outdoor requirement? 

Sharyn


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## bbigelow666666 (Feb 13, 2012)

Thanks for the info, all...

Yes scaling back may be necessary...I'm going to shoot for the stars and see what happens. If anyone has more info about hardware or software that would be great. Thanks!


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## Esoteric (Feb 17, 2012)

One question that makes all the difference in the world. Are you trying to see this during the day or doing it at night?

At night I have projected a 60'x45' image with 2 2000 lumen projectors and a laptop running Pro Presenter with an output to a Matrox DH2G.

We do installations like this all the time (haven't done an outdoor one yet). You are making it too complicated.

The only problem I see is the size ratio. You have a 7:1 width to height ratio.

So for me, you would need to be producing your own content because you are going to be losing the top 1/4 of the projection.

If you do custom content, you could do it with 3 2500-3000 lumen 16:9 projectors with a PC running Pro Presenter and a Matrox TripleHead2Go.


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## museav (Feb 17, 2012)

Esoteric said:


> One question that makes all the difference in the world. Are you trying to see this during the day or doing it at night?
> 
> At night I have projected a 60'x45' image with 2 2000 lumen projectors and a laptop running Pro Presenter with an output to a Matrox DH2G.
> 
> ...


I know ProPresenter on a PC and a DH2G/TH2G support multi screen presentations, but I thought the edge blending module for ProPresenter only worked with Macs and only with ProPresenter 4, not with the latest ProPresenter 5. This somewhat gets into the general issue of the desired quality. Having what appears as one continuous image takes more than having one image broken up into multiple projected images arranged side-by-side with some gap or transition between them. And the latter may be quite acceptable for your application, it all depends on what you are trying to do and what is important to you.

A 104' wide image with three projectors and no overlap for edge blending is a 34'-8" wide image per projector. With 16:9 format projectors that's 34.667' x 19.5' per projector. That's 676 square feet of image area per projector, so 2,500 to 3,000 lumens is 3.7 to 4.4 ftL. And that is assuming you get the full rated output, lens optics, lamp life, etc. could reduce what you actually get. With that projected image brightness street or walkway lights, lights from nearby traffic, nearby building lights, etc. could wash out the image. So it's not just an issue of being at night but also of what other ambient light sources may be present.


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