Many times overlooked and probably one of the most important things to get right! In order to fully emerge into the virtual world, it's important for your senses to recognize it as what you would normally see when sitting in the driver seat of a real car. This should be as close to real life as possible. Another misunderstanding is that you need to tweak the FOV (Field Of View) per car/track – nope, there is only one right FOV for your sim rig setup.
Field of View determines how wide your view into the virtual world is represented in the game. It’s the measure of the angle from the left to the right edge of the screen (in the illustration on the right it's being depicted as the bottom to top, the principle stays the same), describing a circular motion around your head. Make it big and you will get a fish-eye view, small and you end up looking at a post stamp in the distance. The trick is to get it as close as real life as possible. For obvious reasons, it's what you are used to seeing in everyday life. This applies directly on what you see on the screen when attacking Eau Rouge in your virtual vehicle, you want it to look as much as it would in real life as possible. In this way, your senses can more easily process the cues you need for braking and hit apexes.
The benefit of a smaller Field Of View becomes apparent when dealing with small changes in your car's balance. Take for example the situation where you are developing a small slip angle when exiting a turn. Relative to a fish-eye view, you will notice a bigger rotation with a small FOV, exactly what you want to see when trying to correct it with minute wheel inputs.
"The field of view (also the field of vision, abbreviated FOV) is the extent of the observable world that is seen at any given moment" Wiki.
Another important factor is the distance to your monitor. In order to get the most out of your screens, or in other words to have the biggest FOV, you need to get your monitors as close as possible. It often means having to position them right behind your wheel.
Here a good example of how it’s done right:
Unfortunately, it's often done like this:
Some simulators like iRacing have an onboard FOV calculator. For those who don't, here is a link to an online tool: http://www.projectimmersion.com/fov/ which let you calculate the right FOV for your situation.
In the case of a triple screen setup, there are a few things to consider. One is if the sim supports separate rendering of screens. If not it means the picture will be looking warped and stretched out. Basically, it only supports a screen setup where the two side screens are mounted parallel to each other. When it does support separate rendering, the screens should be rotated to have your line of sight perpendicular to the screen for undistorted viewing. See below, the distance to each center should be the same.