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reuben.ahmed wrote:Also,

Posted: 10 Feb 2012, 18:17
by BHawthorne
Also, what's your throw distance for the 2 projectors and the projected image size?

Just trying to get the sense of the amount of room we need to do this.


My personal setups lately have been 6 foot radius arc on the screen 180 degree arc. My GT720's are ceiling mounted approximately 10 foot back. They project a 72" projection height. The screen is 220" linear run. This sort of setup 100% requires a pre-warping utility though. You can't achieve proper setup without it.

Aviation Xtreme uses two of my screens in that configuration.
https://aviationxtreme.com/

The 2x1L 180 degree screen can be scaled down uniformly as needed.

Just the post I was looking

Posted: 30 Apr 2012, 10:55
by Ghetto
Just the post I was looking for,as some may know I have been using 3x 750's on an nvidia card. All in all Iam happy with the setup which gives me 3 flat panels at 1200 by 720 mm ..
But there is a down side,
1, to get the projectors in the correct position they are stacked one on top of the other meaning I have to play with the keystone angles which in turn cause focus issues between the top of the screen and the bottom on the 2 outer screens..
2, I fly mostly helicopter sims which means I am really missing the projection on the lower half of the cockpit, my screens show a good wide aspect but I need more height..
Solutions?
1, I was considering going rear projection but this will mean a lot of space needed behind the screen.I also thought about going portrait with the 3 projectors to gain a higher (taller)FOV ..
2, to get a much taller screen I could only think of using another 3 projectors for the lower half giving me 6 projectors in all, downsides would be the cost, the extra card power needed, 3d goes out the window (I really love the 3D), and FSX will probably run like a pig at that high a resolution..

So to here that using 2 projectors can created a much larger FOV is of great interest.. So basically by increasing the throw on the projectors we can get a much larger screen area covered.. Simple but briliant.. The only thing with my set up is that I really like to be close to the screen which means I will need a fairly tight radius when it comes to achieving 160 to 180 deg POV..Looking at the Aviation extreme vid the pilot seems to be a fair way back from the screen but It looks like the screens themselves are based on a promotional display product as seen here. http://www.displaywizard.co.uk/quick-pop-up-display-stands-curved-frame-5-sizes.html Im sure they could be altered to get a tighter curve and can be picked up fairly cheap with a plain white covering that could then be pained with screen goo.

My end project will be building some sort of cockpit like seen here http://www.flyit.com/component/content/article/1/3-professional-helicopter-simulator.html Ill probably build it out of MDF or something like that.. But Im guessing that the closer the screen is to the cockpit the more chance I will get of the cockpit getting in the way of the projected image.. Maybe rear projection would allow me to get the screen closer not sure which would be the best route to go.. which brings another question on how extreme can the curve be before focusing the image in the centre will create distortion on the left and right? You mention 6ft arc is that optimum? can I get away with maybe 4to 5 ft arc?

FSX display? For now I simply set FSX to wide screen mode in the .cfg file and set a resolution of 3840x720, this gives a wide view but just the forward view.. If I want true 180deg FOV without everything being distorted how is that setup in FSX , for example if I look to the left I want to see the view out of the door not just the left side of the forward view, If I look down I want to see the lower cockpit bubble window and pedals etc (if that makes any sense?) just zooming out makes everything go all distorded.

In regards to motion, I too had seen the dbox and other expensive motion units and in the end opted for a stage 1 kit from Simxperience, basically uses 2 scn5 actuators to push your seat 2dof it was designed for car racing games and works a charm for them but I needed to get it working with FSX which it does not support.. I then came across this site http://buggies.builtforfun.co.uk/Sim/index.html where a guy has created a bit of software to control the actuators via fusipc from FSX.. Got it up and running over the weekend and it works like a charm..So this got me 2dof motion for $2000 quite a saving on the dbox setup and if you study the BFF site you will see he also has plans on a more DIY approach so you could get the price down even further using wiper motors and the such..

Anyway chime in if you have any tips oct ideas and Ill crack on with putting it together..

Great post!

Posted: 18 May 2012, 19:17
by rich0550
Wow, I never thought could do this with 2 projectors.

Can anyone chime in on the benifits of 3 versus 2 projectors for surround gaming. Currently I have a cockpit with a 1024 x 768 projector, 3000 ansi lum, and 7' high (wall sized display) i think about 9' diagnol. The image is not good enough for todays games really.

can 2 projectors achieve simiar results to 3?

Hey all, hows your setup

Posted: 16 Oct 2012, 12:28
by OmniAtlas
Hey all, hows your setup coming along?

I am also planning to build a 180 degree screen with 2 projectors. Thanks for the inspiration!

Is the Optima GT720 still the recommended projector, or are there better or more affordable ones in the market?

The DisplayPort to Dual HDMI adapter is out by Zotac so that means no more TH2GO, and that now we can do dual screen/projector setups on one nvidia card. http://www.zotacusa.com/zotac-displayport-to-dual-hdmi-adaptor.html

Could you not do dual screens

Posted: 17 Oct 2012, 20:52
by benjimoron
Could you not do dual screens on an Nvidia card before?

Also, not sure that you'll get 180 degrees from 2 PJ's. I've not got enough experience to say for sure but I would've thought it'd be limited to less than that realisticly.

I've read that the Nvidia

Posted: 18 Oct 2012, 10:16
by OmniAtlas
I've read that the Nvidia cards can only output to 3 or more, not 2.

As for 180 degrees, BHawthorne has his setup with 2 projectors --http://www.wsgf.org/forum/15158/multi-projector-build-20?page=2

I thought that 3 screen was

Posted: 18 Oct 2012, 13:36
by benjimoron
I thought that 3 screen was for 3d only, ie if you want 3d then you have to use 3 screens. 2d can do two screens I think. You may want 3d though.

I'm not sure that BHawthorne got 180 degrees from 2 PJ's, you'd have to ask him. I'd imagine the image would start to get awkward at some point.

This thread and his links to

Posted: 19 Oct 2012, 11:24
by OmniAtlas
This thread and his links to his commercial projects indicates he has setup 180 degrees with 2 projectors. Why would the image get awkward?

The reason I am going for a 2 projector setup is reduce the startup cost. I'm also looking at setting it up specifically for a 1 seater trainer such as the Jetmax trainer from Flight Deck Solutions, so I don't need such a wide radius (I'm only looking at something around ~ 1 m).

I'm just surprised there aren't more setups like these, I could see someone easily commercializing this for the gamer/simulation market. With short-throw 720 projectors coming down to ~ 500 USD each and if someone could bring out a setup with 2 projectors and a 180 degree screen warp with an easy to setup hardware and configure system, a ~ 1500 USD complete solution visual system would be an instance buy from me.

Update on my setup, I tried 3

Posted: 22 Oct 2012, 09:24
by Ghetto
Update on my setup, I tried 3 projectors on a curved screen, but found a few issues, When I wrap the screen around me so its about 2 meters wide with steep arc, the amount of light reflecting around from those projectors completely washes out the image, I have purchased some screengoo in a grey so that this might fix the issue, but for now I have opened up the arc of the screen to counter the reflections.. I am also finding that 3 projectors at 16x10 is just too wide at present, I have currently settled for the centre screen @ 16x10 with the 2 outer projectors in 4x3 II mode, then using immersive display pro software i overlap the 2 outer projectors 25% over the centre image which gives me an image 3.5 meters by 2 meters high roughly...
Just a sub note, the gt750 projectors I am using have no zoom fuction so it was always a major pain alligning them up even when I used 3 flat screens, trying to allign them up so the images were the correct distance from the screen and them butting the images up together was a nightmare.. It wasnt until I got the elise warping software that I realised I no longer needed to worry so much about getting the projectors lined up, I now just get them fairly close but make sure my projected image is bigger than the screens I am using and then use the software to size the images where I want them, kind of like have fine zoom adjustment and positioning on the projectors.. That being said, I just did a quick warping on a curved screen for windows descktop, and after the correction you can see a noticible drop in quality of the imagefor wxample with the warp off I can read fine text in the shortcuts on the descktop or in the dropdowns on menus in windows but with the warping on those same items are barely readable. Maybe someone can chime in if they know a way around this, maybe I am just overwarping the image?

Ghetto wrote: That being

Posted: 29 Oct 2012, 12:47
by OmniAtlas
That being said, I just did a quick warping on a curved screen for windows descktop, and after the correction you can see a noticible drop in quality of the imagefor wxample with the warp off I can read fine text in the shortcuts on the descktop or in the dropdowns on menus in windows but with the warping on those same items are barely readable. Maybe someone can chime in if they know a way around this, maybe I am just overwarping the image?


Is this a software limitation? I tried out the demo of Immersive Display Lite 2 and it was pretty blurry with it enabled. Have you tried the other software out in the market?

ScreenGoo has reflective

Posted: 31 Oct 2012, 19:07
by rdqlus
ScreenGoo has reflective particles in the mix so it probably isn't what you're looking for. I tried it for my screen and it was way too bright. You probably want a neutral grey paint. Go to Home Theatre Shack and ask the DIY screen guys what you should use (it'll also be cheaper).

HTS DIY

The drop in image quality that you're experiencing is due to the warping function. You're effectively taking a 1280x800 image and compressing all the information in that picture into a lower resolution (yes, that's really what you're doing). Will work fine for games/video but fine features such as small font text will suffer.

Perhaps take a look

Posted: 01 Nov 2012, 14:46
by chrisbrackenbury
Perhaps take a look here

Regards chris
Pixelwix.inc

Re: 3 Projector Build

Posted: 30 Nov 2012, 07:27
by Iceking007
I'm wondering how this Optoma GT720 projector does with the DLP rainbow effect; I was steering clear looking at LCD. I did watch the YouTube video you posted however it's not the same as being there; does this projector produce that rainbow effect at all?

If not I will be sold on two for my 120 deg fov. .. Just haven't decided on front or rear projection.

Thank you for your input.

Re: 3 Projector Build

Posted: 30 Nov 2012, 10:28
by benjimoron
From what I've read, it's people that can see the rainbow effect, rather than the projector producing it or not. I've never seen it, but someone else with their eyes could look at the same projector and see it if you see what I mean?

Re: 3 Projector Build

Posted: 12 Dec 2012, 22:16
by rdqlus
Iceking007 wrote:I'm wondering how this Optoma GT720 projector does with the DLP rainbow effect; I was steering clear looking at LCD. I did watch the YouTube video you posted however it's not the same as being there; does this projector produce that rainbow effect at all?

If not I will be sold on two for my 120 deg fov. .. Just haven't decided on front or rear projection.

Thank you for your input.


I can see the "rainbow effect" if I take a white window and quickly move it around over a black background while blink my eyes quickly. I've never noticed it any other way so it hasn't been a problem for me.