Our beautiful sanctuary was designed for speaking... and not much else, things are very different today. For a few years after we got the place we used a common portable projector and set it on a board on top of the pews to project onto one of the side walls. This was a crude setup with low quality results and a major pain to setup for the random 3 minute video used during a church service or midweek.
Due to the challenge and low quality of this setup we opted for a more permanent setup. The solution was to mount a projector from the back and put a screen in the center above the stage. Having a screen up there all the time would be a bit of an eyesore so we opted for an electrically operated roll up screen. The screen we got was a 150" 4:3 screen, was about 63 feet from the projector giving a throw ratio of 6.3 feet per 1 foot of screen width. This throw ratio is large for a common projector.
Fortunately (kind of) I found a used projector and special long throw lens on ebay in Febuary of 2012. Enter Epson PowerLite 8300i with ELPLL04 lens it cost us a total of $917 which seemed like a really good deal at the time. The projector worked decently while 'new', however, we found that during bright days the screen would be washed out and barely visible. 2 years after installing, the image was barely visible unless completely dark in the room. A new lamp didn't seem to do much so we had to accept it was time to kick it to the curb...
Optics, Calculations, and shopping
Before asking for some serious cash for a new projector I decided to spend some time doing research on projectors. Some important considerations whenever bying projectors:
- Brightness: In lumens of output at the projector
- Candlepower/lux: light measured at the screen (what we ultimately care about)
- Lens F-stop: An optics measurement, an increase of 1 results an a power of 2 decrease in output
This time I really wanted to know what kind of light to expect at the screen. Dad got a lux meter back when we worked on sanctuary lighting so this allowed measurement of light at the screen and room light.
The Old
To measure the 'current' setup I turned the projector on and measured the light at the screen at 80-85lux or about 8 footcandles. I calculated the expected light at the screen (5200 lumens reduced to 2977lumens from the long throw lens). Then using the actually measured light at the screen suggested 700lumens (not the supposed 2977 lumens)! My best guess is the LCD panels were worn out.
The New
After quite a bit of research I came up with three options: new projector in back, new projector mounted on the ceiling, or add blinds to the windows. I ruled out the blinds as they wouldn't reduce all room light, were expensive, would stick out from the wall, and operate slowly.
I was leaning towards keeping the current position for simplicity of installation and maintenance but this required an expensive long throw lens and was kind of ugly. While looking into an optional video over ethernet option I got interested in mounting from the ceiling which was something I had considered the first time around...
After much research into projectors which included figuring out how to adjust for the light reduction due to lens f-stop I settled on a Panasonic PT-EX510U which has a rated lumen output of 5300 which reduces to 4821 when adjusting the lens. It had all the necessary features including motorized lens shift, zoom, and focus. Motorized controls were required since I can't physically adjust it.
Ceiling Mount
With such a high ceiling using a ladder from below to mount the projector wasn't an option. So after measuring carefully with a laser level I found that mounting it to the front facing wall of the attic organ room was the correct spot. It is mounted with a winch and has 3 redundant safeties that would all need to fail at the same time for it to fall on some poor soul.
HDMI/HDBaseT/Signal Hades
The main challenge other than actually mounting the projector on the ceiling is to get the video signal to it. Enter HDBaseT which is a protocol to transmit HDMI, IR, ethernet and other signals over a single CAT6 cable. This is a protocol supported by multiple manufacturers and seemed like a good option. Cable routing went from the back of the sanctuary, under the stage, up to the attic and finally to the attic center where the new projector is mounted from. A long run of over 100' but within the HDBaseT spec.
Being the digital age I decided to have all signals go over HDMI it is pretty ubiquitous and straightforward to use... or so I thought. I used an HDMI matrix to allow multiple inputs to be connected to the projector and to be able to preview a mirror of the signal going to the projector at the back. Now as probably everyone noticed to my dismay the signal was not stable. My first guess was the HDBaseT was getting interference so I upgraded from HTBastT Lite to the full HDBaseT with a 330feet limit. I re-seated the ethernet connector checked the cabling, bypassed the HDMI matrix, read about the many woes of working with HDMI, tried different inputs, different software... pretty much anything I could think of. After multiple months of frustration we found a few changes that seemed to have fixed the problem:
1. We put the power adapter for the HDBaseT receiver on a power strip with good noise filtering
2. Updated the video card drivers on the sound board computer and switched the refresh rate
The last one seemed to fix the problem that always seems to happen only with that computer. While it seems obvious now and i'm sure I tried it before, previous updates mayhave failed. I also added a couple of HDMI ghosters which keep a signal going to the computer even if the projector is switched to a different device.
So it was quite a long process but our setup has been working well for months now without any issues. Our new setup works and looks much better than before.
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