Screens for Worship Facilities
By: Jim Hoodlebrink
Here are some commonly asked questions by church leaders regarding projection screens.
What do I need to think about when planning for a projection screen?
There seem to be so many technical terms relating to projection screens. What do they mean?
Contrast is the surface's ability to accurately reproduce and differentiate light and dark characters and backgrounds, or light and dark areas of an image. A front-projected image is created by a pattern of light on a light-colored surface. Naturally, the white areas are generally very bright. The dark areas, on the other hand, are simply the absence of projected light on a light-colored background—not solid dark objects like the opaque inks we see on a printed page. A projection screen that preserves strong dark tones actually makes the light-colored areas look brighter by comparison.
Ambient Light is the light present in the room where the image is projected. A projection screen that rejects ambient light will retain better dark areas when the lights are on in the audience area—hence, it will have better contrast under those conditions. This quality is very important for situations where the audience members are active participants in the presentation, or where the speaker wishes to move through the audience area, and whenever notes are likely to be taken.
Resolution is the clarity of the projected image. Resolution obviously depends primarily on the projector's output, but the smoother the projection surface, the less likely it is to create a distracting moiré pattern when a high-resolution video or data image is projected on it.
Uniformity refers to the consistency of the screen's performance when viewed from various points off the projection axis (both horizontally and vertically), and when the brightness of the center of the image is compared to the corners. Typically, screens with low gain, or brightness, provide the most uniform images.
Projection Format refers to the screen's size and shape. This depends on height and width of the projected image. 4:3, 16:9 and Cinemascope are the main formats for projecting video. Computer power point may mean that 16:10 is the best way to go.
How can I figure out what size I'll need?
One mistake we see involves screen size in comparison to font size. You have to consider how the screen is going to be used. Many times, it is to use for projecting song lyrics and other text. You need to consider the legibility of the text—make sure it can be easily read from the last seat. If video is the primary content, then you have to place more importance on those distant seats, as opposed to the optimum seat locations.
While we're on the subject of screen size, also consider having more than one screen in sanctuaries or other large rooms. This might allow you to better reach everyone in the room and might allow for smaller screens.
Should we use front or rear projection?
This sounds a bit complicated. Isn't it really just a case of shining a light on the wall? Or, do I need to bring in a professional to help?
Jim Hoodlebrink (CTS) is product manager of Information Display Systems for Draper, Inc. Draper manufactures projection screens for any venue or use, along with related products, such as motorized lifts for video projectors, www.draperinc.com.