Projectors—like consumer TV sets—are all expanding, moving to widescreen formats. Yes, you will still find 4x3 XGA (1024x768) models out there, but everyone wants widescreen. All new notebook and tablet computers are widescreen, with the notable exception being Apple's iPad 3. But even that product plays video back at 720p HD resolution.
Now would probably be a good time to point out that the term “video projector” is basically obsolete. All projectors can show video, and a growing number of projectors support at least one HDTV format (1280x720p) natively.
So what you want is simply a new projector. What you'll want to focus on more closely is what resolution and aspect ratio you need to support.
The most common widescreen aspect ratio is 16:9, or 1.77:1 to be exact. This is the screen height and width for 720p and 1080i/p video content. The thing is, 1280x720 and 1920x1080 are video formats, not computer display resolutions. Examples of the latter would include 1280x800 (Wide XGA), 1366x768 (also Wide XGA), 1680x1050 (Mac), and 1920x1200 (Mac, WUXGA).
Here's the rub. If you are showing 16:9 video on a 16:10 screen, you'll have unused, thin, black “letterboxed” bars running horizontally across the top and bottom of the projected image. But if you try to project 16:10 graphics on a 16:9 screen, you'll wind up with thin, “pillarboxed,” vertical black bars at the left and right edge of the screen.
There's no easy answer here, except that you should pick the projection aspect ratio that matches a majority of your projection needs. If that is playback of live and recorded media video content, then go 16:9 and format your PowerPoint and other graphics to the same aspect ratio.
Light me up!
The next question concerns how much brightness you'll need. The fact is, it takes a lot of horsepower to overcome relatively low levels of ambient light and still produce “contrasty” images on a projection screen.
A better question might involve just how bright you want the images to appear on screen. The SMPTE (Society of Motion Picture and Television Engineers) luminance target for motion picture screens is about 16 foot-Lamberts, but to get that from a large screen—say, 20-feet wide—requires about 3,500 lumens to start with. And the SMPTE specification is for a darkened room.
In your case, you may need 2x or even 3x that level of brightness to overcome ambient light spill from house lighting, stage lighting and windows. Let's say you are showing IMAG video on a 16x9, 12-foot-wide projection screen with unity gain (1.0), and you need about 60 foot-Lamberts for a bright enough image under full lighting.
Doing the math, that 16x9 screen measures 6.75 feet tall by 12 feet wide, for a total of 81 square feet. To calculate the required lumens, multiply 60 (ft-L) by 81 (ft2) and you wind up with 4,860. So 5,000 lumens is the minimum for your application.
If you plan on using long projection throws and long-throw lenses, that number's gotta go up as these lenses have smaller apertures and pass less light. Projector manufacturers should be able to give you the aperture ratio for a given lens so you can calculate the decrease in screen brightness and make up for it (possibly with higher-gain screens).
Hook me up!
?Pay careful attention to the connector complement on your new projector. Analog signal interfaces are on the decline, while digital interfaces like HDMI are de rigueur now. Even the 10-year-old DVI interface is on its way to retirement, to be replaced by DisplayPort in the next few years.
For any installation projector, you should have at least one if not more digital display inputs (HDMI and or DVI), plus a USB port (useful for software upgrades and automatic playback of certain file formats) and an Ethernet connection (for remote operation and diagnostics).
Computer manufacturer support for the 15-pin VGA jack is phasing out. Newer notebooks and ultrabooks will only offer DisplayPort and/or HDMI, and you'll need adapters to use MacBooks, iPads, and other tablets with VGA. Might as well start using HDMI and DVI.
Here's another compelling reason to go digital: Analog video connections are fast disappearing from DVD and Blu-ray players. Current-model Blu-ray players offer only an HDMI output jack and a composite (480i) analog video jack.
What's more, copy-protected content played back through DVD and Blu-ray players, as well as set-top boxes and game consoles, can disable existing analog component video connections. So you can't even rely on older Blu-ray or DVD players to do the job.
Make sure you have enough digital video inputs. USB ports are also handy, as are Ethernet connections for remote monitoring. Lens shift is a plus and will make your life easier. And by all means, go widescreen—there's no reason to sit on the sidelines any more.
Even so, do your homework. There are plenty of projector guide websites that are ready to help you, like projectorcentral.com. Figure out your total cost of ownership, including lamp changes, and come up with a realistic amortization schedule (three to five years).
Today, you can get four times the brightness, twice the resolution, better optics, digital interfaces, Ethernet connectivity, compact profiles, lighter weight, and lens shift; all for 20%-25% of the 1990s pricing. It's hard to go wrong.
Image courtesy of Clair Nashville and First Baptist Church Hattiesburg, Mississippi.
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