If your church is anything like mine, then you have a volunteer AV staff. Maybe one or two people run sound. Someone else designs and runs whatever programs are used on the PC. Someone else handles the screen (when is it up, down, on, off, etc.). The key is we are all lay people, volunteers. So how do lay people develop a system that works seamlessly and looks good enough that everyone in the congregation will accept it? My first response is…consult with a professional. But you can and should be an educated customer. I’ll start by giving you some suggestions when it comes to your projection screens, which are the most visible parts of your system. If you pick the wrong screen, everyone notices. Hopefully these tips will save you some time and future grumbling!
So what do I need to think about when planning for a projection screen in a worship facility? There are several questions you need to address. What should be the proper size of the screen for the size of the church? Seating arrangement and floor to ceiling height may affect this. Also, what is the layout of the church? Where can the projector be mounted? What type of surface is best suited for the lighting? What kind of content will be projected onto the screen? There seem to be so many technical terms relating to projection screens. What do they mean? Let’s start with the basics.
Gain is a relative measure of a screen’s reflectivity. Gain is a measure of brightness as compared to a block of magnesium carbonate, which serves as a standard for gain of 1.0. Gain is the statistic most frequently cited and charted to compare projection screen surfaces. A gain chart can also help in judging uniformity (see below). The flatter the curve in the area where viewers are seated, the more consistent the image they will perceive.
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 powerpoint may mean that 16:10 is the best way to go. How can I figure out what size I’ll need? Base it off the room size, ceiling height and type of screen preferred—roll down, fixed or rear projection. Consider its use—is it primarily for following a powerpoint, displaying hymn lyrics or showing video? 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 intended 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 could allow you to better reach everyone in the room, and might allow for smaller screens.
Should we use front or rear projection? For new construction, or renovations where dedicated space for a rear projection room is possible—rear projection is ideal, because there are no ambient light issues.
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? While anyone can plan and implement projection strategies, we always recommend bringing in a professional—an AV consultant or dealer. They have the experience to see potential problems and come up with the best and most cost-effective solutions.
I will get in to more specific options in part 2…stay tuned!