How to Determine Projection Needs
for Houses of Worship
We are seeing many churches reaching end-of-life on their current projection systems and looking to upgrade or replace. But beyond just settling for a newer version of what they have, most churches are unsure of how to move forward. How do you know what improvements can be made with today's technology? What are realistic expectations to have from a new projection system? How do you future-proof the church while keeping costs reasonable? These and many other questions plague church staff, and sometimes paralyze them to the point where nothing is done for months, sometimes years!
This article will shed some light on how to go about answering these questions and help you determine what your needs are. From there, I'll show you how to use that information to narrow down your options. Here we will deal primarily with the issues of screen size, placement, viewing angle, and materials. Once those things are settled, you can go about figuring out how many lumens you'll need from your projector, which is a subject I'll tackle next month.
When I encounter new church clients, I always start with the simple question: "What's not working in the current system?" This will usually generate responses ranging from, "We can't see the image because it's too dim," all the way to, "The system only works about half the time and we don't know why." We must start with the most obvious pain points and work from that foundation because those have to be addressed with any new system. Sometimes, the image is too dim because the projector doesn't have enough lumens to provide an adequate image at the desired size; other times the ambient light in the space is overwhelming the image on the screen. Many times, it is a combination of these and other issues. Bottom line: write down a list of what is not working and what complaints there are with the current system. Make sure to include in the discussion not only those people who operate the system, but those who sit in the congregation week in and week out, as they will likely have a valuable perspective and insights you may not think of!
Screen Placement & Viewing Angle
Another common complaint, particularly in rooms that have a wide seating layout, is that the screen cannot be seen properly from all viewing areas. This is due to the "viewing cone" being narrower than the seating. The viewing cone is an angular measurement for a projection screen material in which the image retains at least 50% of its brightness. For example, a screen material with a 70 degree viewing cone will serve a much wider seating arrangement than a material with a 30 degree cone. However, there is generally a tradeoff between viewing cone and gain. Gain is a measurement of how much of the light being projected will be reflected back to the viewer. Materials with narrower viewing cones sometimes have the benefit of higher gain, where those with wider viewing cones usually have a more uniform gain.
The general consensus for projection in a public space like a church is that it's better to have a lower gain with a wider viewing cone —unless your space is long and narrow, where a wider viewing cone becomes unnecessary. The lower gain with a wide viewing-cone material can be compensated for with a brighter projector and, fortunately, the number of high brightness projectors on the market that can provide the right amount of lumens (brightness) for your screen size has increased dramatically in the last few years.
For wide rooms, it is important to establish whether you want one large screen or two smaller screens; the side screens usually sit at a slight angle to better accommodate the sides of the seating area. Wide viewing cones combined with this slight mounting angle means the best of both worlds for all viewers. However, having a single, large screen can also be the right call if there is sufficient viewing distance between where the projection screen is mounted and the seats. In my experience, the large center screen is best utilized when you have a deep stage area. This is because you don't want people in a shallow room to crane their heads at a steep angle to see the screen when they sit in the front rows. Increased depth (distance to the screen) allows this angle to decrease, and provides a far more comfortable experience for everyone. Of course, you may want one large center screen and two smaller size screens that can handle separate content. There is nothing wrong with this, but be sure that you can handle that configuration! While it is an awesome system to run, it does require additional hardware and personnel to run that smoothly every weekend.
Viewing Distance & Screen Size
Another important determining factor to discuss in detail is screen size. This topic can get quite convoluted very, very quickly. The general standard is that the maximum viewing distance should be between 3x and 6x the screen width. This means that if the seat furthest away from your screen is 75 feet, the recommended screen width would be a maximum of 25 feet (3x) and a minimum of 12.5 feet (6x)! Assuming you are going to either transition to, or continue with, a 16:9 aspect ratio, your diagonal measurement for those sizes would be 344 inches (3x) and 172 inches (6x), which is likely much larger than you thought!
In my experience, these numbers can be fudged a bit, especially if you are not showing fine detail on the screen (like spreadsheets). Most churches are showing lyrics, videos, and images, so you can get away with smaller screens that would otherwise not be recommended. Of course, some churches want that impact factor of huge screens, but if you are simply asking how big the screens need to be, know that the way to get into the right ballpark is to measure the distance from the screen to the furthest viewing seat and divide that by 6, and that will give you the suggested screen width. For a smaller church with a shallow room, you can probably get away with dividing by 8, but you don't want to go past that. A quick way to check on your numbers is to grab some painter's tape and measure out the horizontal on the wall where your screen needs to go. Then go and stand or sit in that furthest away seat and see what you think. Generally speaking, you'll find that even a 75-inch TV is not going to cut it, despite how inexpensive they are these days.
The last topic I am going to cover is the screen material. I have mentioned ambient light-rejecting (ALR) screen materials in my previous articles, but what we haven't covered is when they are critical and when they are a luxury. While I am a firm believer that most projection systems can receive significant benefit from an ALR screen, there are some spaces where they are absolutely critical. Rooms with high amounts of ambient light that cannot be controlled are prime candidates for ALR screen materials. While ALR screens do carry a higher price tag than traditional matte white screens, the difference in price is fairly negligible and the cost-to-benefit ratio falls fairly high on the side of the benefit, which makes it well worth the small up-charge.
How do ALR screens work? Well, the exact science each manufacturer uses is highly guarded, but one aspect is that with a matte white screen, you will never get true black from your images because of the surface color. Similarly, traditional high contrast screens (grey in color) mean that you are not going to get true whites because of the surface color. Along with playing with the color of the material, manufacturers may also integrate some form of optical elements into the screen material to help control the behavior of light coming from different angles. So, an ALR screen helps increase your contrast ratio (difference between white and black) by giving you brighter whites and darker blacks, while also using proprietary technology built into the materials to reject off-axis light. What does that mean? If light hits the screen from an angle that is different than that coming from the projector, it will not be reflected back at the viewer and show up on the final image. This is an exciting and awesome technology that has taken projected imagery to an entirely new level. As a system integrator and designer working in public spaces, I can worry a lot less about light spilling onto the screens from my lighting system and from windows, skylights, etc.
Is ALR right for you? The best answer I can give you is to find a system integrator or consultant who can bring in samples of different screen materials so you can see exactly how different materials react in your space. Some screen manufacturers will even provide samples of their materials to you for a small charge. Da-Lite, Draper, Screen Innovations, dnp, and Stumpfl all have ALR products, and I strongly encourage you to start your research so you can experience the added depth, contrast and color saturation available now with projection systems!
Tim Adams is president and chief systems designer for Timato Systems, an audio/video integration company specializing in servicing the sound, lighting, video, projection and live-streaming needs of churches and other houses of worship. He can be reached at firstname.lastname@example.org.