by BHawthorne » Wed Mar 29, 2017 3:28 am
I really don't like to go over 90 degrees per projector. What happens if you do the projection begins to have depth focus issues. Projectors are designed for a flat surface to project on. When we re-purpose them for a curved surface, we now have to take into account that the length of the projection is different at the edges and the center now. That is the depth of the projection. Projectors are designed with a focus range. Doing a bit of math, here are common designs:
Common screen designs (Nthusim Plus):
180 degrees / 2 projectors = 90 degrees per projector + 15% overlap for edge blending (This is the most extreme I suggest per projector)
180 degrees / 3 projectors = 60 degrees per projector + 15% overlap for edge blending (The most common design of screen)
225 degrees / 3 projectors = 75 degrees per projector + 15% overlap for edge blending (Anything over 180 degrees is typically P3D, X-Plane, DCS World or FSX flight simulation only)
Exotic screen designs (IImmersaView SimVisuals)
270 degrees / 4 projectors = 90 degrees per projector + 15% overlap for edge blending (Specific to flight simulation only)
360 degrees / 5 projectors = 72 degrees per projector + 15% overlap for edge blending (Specific to flight simulation only)
360 degrees / 4 projectors = 90 degrees per projector + 15% overlap for edge blending (Specific to flight simulation only)
If you have a niche case where you need over 3 projectors we can sell you a license of ImmersaView SimVisuals for the cost of Nthusim Plus to ensure your hardware calibration needs are met. We offer this option only on a case by case basis depending upon your project needs. 99% of the time Nthusim Plus does everything needed.
In general, you need to configure the vertical and horizontal aspect ratio correct to each other for your screen design. If it's not locked in uniform when you roll the camera of the visuals it'll be noticeable. Any non-uniformity or compression within areas of the calibrated screen will behave oddly.
Below is an example of an incorrectly calibrated screen using Nthusim Plus. The calibration was "eyeballed" and not measured out the calibration points in a uniform manner. This caused odd distortion within P3D. It's important to get the screen design uniform and then calibrate it uniformly. The easiest way is to use a "cross-line" laser level. Typically, you can get one for around $50. You can also just manually measure out the grid with a steel measuring tape and use painters tape to tape off the grid to calibrate to. I have done both ways over the last few years with good results.