So you’re getting ready to enjoy the awesomeness that is a big old projection screen in your home theater, which is excellent. There is nothing like the lights going down, and your show starting up on your screen.
Of course, while you are designing your theater, there are many screen related questions like, What should the viewing distance be for my seats? What kind of screen should I get? And, what are viewing angles anyway?
The shortest answer is this image below, the viewing angle is shown on this picture:
On a high level, this is how ‘wide’ the image is to your eyes, when you are watching the screen.
But, you want more than that, and you should. A properly designed home theater will take into account the viewing angle – and not just put the largest possible screen that can fit onto the wall.
To explain this more, we need to discuss something called Field-of-view.
Field-of-view is basically the visual area you can see, when your eyes are fixed on a point (meaning, you are not looking around at things, you are staring at one point). The more of your field-of-view that is taken up by your screen, the more immersive the image will be.
While you can technically see nearly 180 degrees, from left to right, you can’t really see that large of an angle with any clarity or with any resolution. What you see on your far peripheral vision is very hard for your brain to concentrate on, so instead you focus on what is in front of you.
You want your screen to be inside that comfortable field of view, and you want a viewing angle that will give you the amount of immersion that you desire. Now, even though that level of immersion is a personal preference, there are some standards to work with .
The Society of Motion Picture and Television Engineers (SMPTE) define the ideal viewing angle at 30 degrees or more. THX defines the ideal viewing angle at 40 degrees or more.
Now that 40 degree or more number, that THX recommends, is based on a 16×9 Screen Ratio. However, since more and more home theaters are using a 2.39:1 ratio for their screen, we really need to discuss that ratio more than the big screen TV ratio.
The THX recommendation for a cinemascope (2.39:1) screen is that the farthest seat, in the center of the theater, has a viewing angle of 36 degrees.
So in your theater, you are likely going to want to have a minimum viewing angle of 36 degrees.
To add onto this discussion is the issue of image resolution.
As the resolution of displays keeps increasing, the comfortable viewing angle will also increase. This means that with a higher resolution display, such as a 4K display, you can comfortably enjoy a larger viewing angle that you can with an old 480p display.
With this increase in resolution, with the use of CinemaScope ratio screens, many theater owners are creating theaters with 60 to 70 degree viewing angles, or even higher.
There is no perfect answer here, there is no ‘exact’ viewing angle that you should use in your theater. As a general rule though you will, most likely, end up with a viewing angle that is greater than 40 degrees.
Ultimately, as is the case with most of the decisions you will make about your theater, it comes down to your own personal preference.