Projector Screen Size Selection Tips

Public School classrooms generally order a projector screen that is 60" x 60" or 70" x 70", matte white surface no matter what.

Trade show presenters usually buy the largest screen they can carry (or fit in their booth display). That is generally either 80" diagonal or 100" diagonal, matte white surface.

If this is you, get a straight answer from your sales rep about the carrying size and weight of the screen. And get a sturdy plastic carrying case if your travel plans involve checking a projector screen at the air port.

For everybody else, there are rules of proportion to help determine the screen size that will both look and work best in a room. Naturally, if an ideal screen costs too much or looks too big for the room, it's OK to go smaller.

When determining what size screen to put in any room you will want to answer a few questions first.

Projector Screen Size Questions

1. Projector Native Resolution lets you know which aspect ratio to select for your screen . What is the native resolution of the projector that you have?



2. Ceiling Height allows you to determine the screen height that will fit gracefully into a room. What is the ceiling height of the room that you are outfitting?



3. Distance from Screen to Audience. The people sitting farthest away from the screen determine the minimum screen width. A screen should be at least as wide as 1/6 of the distance between the screen and the viewer farthest from the screen. How far away will the viewer be sitting?

Find out the answers to these questions and you can use a few simple rule of thumb techniques to determine the appropriate screen size.

Illustration of Letterbox Effect and Projector Native Resolution



Projector Native Resolution

First, we want to look at the native resolution (aspect ratio) of the projector being used in the room. This will help you determine what screen format you should go with. Most all projectors nowadays will do both 4:3 and 16:9 aspect ratios. As shown above, a projector with a native 16:9 aspect ratio can letterbox to show a smaller image in 4:3 format. You will want to go by the native aspect ratio in order to get the biggest and best picture.

Ceiling Height

Second, we will want to look at the ceiling height in the room. A screen should be at least 1 ft. down from the ceiling and 3 ft. up from the floor. For example, in an 8 ft. room, a screen should be 4 ft. high at the most. If the room has a slanted ceiling, the screen should be placed at least 1 ft below the ceiling at the point where the screen is going to be installed. This rule of thumb gives you a screen that is gracefully proportionate to the wall and the room. This is especially true for classrooms, boardrooms, and conference rooms where people will be sitting in front of one another.

A home theater application can be a little more liberal with this rule of thumb, unless you have a tiered seating arrangement in a dedicated home theater environment, but I would still think its a good idea to keep it 3 ft. off of the floor. You will be glad you did. If you are mounting your projector to the ceiling, you want the projector to be even with the top of the the screen. Now this rule of thumb is for a maximum screen size. It is OK to go smaller. People focus on what they can see in the center of their field of vision. A person's gaze follows the action from one portion of the screen to the next when the screen is too big (or the person is sitting too close) instead of seeing t all at once. You don't want your audience to get tennis neck.

Distance from Screen to Audience

Finally, we need to look at the distance the audience will be sitting from the screen. For auditoriums, conference, and boardrooms the width of the screen should be no less that 1/6 the distance of the farthest spectator in the audience. For example if the back row of an auditorium is 48 ft. away then the width of the screen should be at least 8 ft. wide. This rule of thumb is for minimum screen size. It is OK to go larger. The important thing is to get a screen that is large enough for the audience in the back row to view comfortably.

How To Apply the Screen Size Rules of Thumb

1. Projector Resolution. I will pretend I have an Infocus IN72 projector, 16:9 aspect ratio for playing Hi-Def movies in a home theater. That means I should use a 16:9 HDTV format screen to get the biggest and best picture.



2. Ceiling Height. My ceilings are 8 ft. high. So my screen should be 48 in. high at the most. That means the largest screen I can fit in my small home theater is 92 in. diagonal 16:9 HDTV format (45 in. H x 80 in W).



3. Distance from Screen to Audience. If I prefer a smaller screen, the rule of thumb that screen width is based on the distance between viewer and screen offers some guidance. For example, if I set up the couch 10 ft. or 120 in. away, then the screen should be at least 20 in. wide (1/6 of 120 in.). That means a screen that is anywhere between 20 in. and 80 in. wide with a 16:9 aspect ratio will fit in my home theater.

Let common sense be your guide. Math can only take you so far. It's more important to like the way your projector screen looks in your installation. If you think the screen is going to be too big for your room, go and measure the space. In general, 120" diagonal is about the largest screen that just feels right in a home theater space. In apartment living rooms, you'd be lucky if a screen that big even fit. Really the recommended size for your basic home theater is in the 100" diagonal range. This will typically give you your best viewing image.