Thu, 12/15/2011 - 07:03
I am designing a 360° curved projections screen.
Important for me to know is the maximum angle that the software can correct.
In other words, could you specify the smallest possible diameter of the circle of the screens ?
We would like it to be a circle of 3 meter diameter, if that is possible of course.
A am planning to use 6 projectors for this.
Could you also advise on good projectors for this matter ?
Thank you.
Kind regards,
Griet Vercruysse
Thu, 12/15/2011 - 18:44
#3
With a 6-projector configuration the shorter throw the better. Look for a projector that is between 0.49:1 and 0.52:1 lens throw. There are several 720p 1280x800 projectors on the market that fit those specs. Even that being said the projectors will dictate the screen size. You can't merely state the screen will be 3 meters then ask what projectors to use. That's going about it backwards. You need to arrange the projectors in a circluar mounting configuration with proper clearance around them for ventallation at the screen centerpoint and work the math on how far the screen should need to be to achieve 15% projection overlap at 360 degrees. When designing multi-projector you're at the mercy of whatever the lens throw is when it comes to screen configuration. First surface mirrors can negate a bit of that issue, but that adds yet another level of complexity and calibration into the mix.
I'm not used to working in meters. I just did the math on that. That would be a 9.8 foot diameter? At that size you would have to use rear projection not front projection. Also, you would probably be able to do it with 4 or 5 projectors not 6. At issue is the depth of the curve you're projecting onto will probably give you focus issues. I suggest no tighter than 12 foot diameter on screens with front projection. The smaller the diameter the greater the variation in distance between the center and the edge of the projections, which will lead to focus problems. When projecting on a circular screen, the surface of the projection is not flat. You have to account for focus depth.
At this time, NTHUSIM only does 3 projectors. You might contact Immersaview for 6-projector options. At issue is not what FOV NTHUSIM can correct, but rather what the game applications you use will allow for maximum FOV. 99% of the games out there will simply not allow for over 180 FOV. The only exceptions being a couple of flight sims. NTHUSIM is not limited by FOV at all. The content you use is the limitation, not the pre-warping software itself.
Independant of the pre-warping utility solution you end up using, 5x1L Eyefinity is your only real COTS solution to 360 degrees. There is no 6x1L Eyefinity or NVIDIA Surround. An alternate option is three Matrox DH2G and either NVIDIA Surround or Eyefinity in combination to push 6 projectors. No single solution can do 6x1L, but a combination should work. At issue with the combination solution is the DH2G does not maintain DHCP capability for video content. Not sure what your end use is for this setup, so I can't make too detailed of a suggestion on hardware.