Crossing the 5,000 Lumen Barrier

By Will Craig

People want brighter projectors for a lot of reasons, not all of which are good. For example, I am sometimes told by end-users that I need to specify a bright projector because of a long “throw” distance from the back of the room to the front. This is not usually a “good” reason. Having a large screen to illuminate is a good reason – and here’s why:

A 120” diagonal 4:3 aspect projected image has an area of 48 square feet. With a typical classroom projector in the 3000- to 4000-ANSI lumen range, this appears to most people to be pretty good, assuming that ambient light is not falling excessively across the screen surface. In larger classrooms, when you’re looking at a 12- to 15-foot ceiling height and a space of 50-75 feet to the back rows, a larger screen is often necessary. A 170” diagonal 4:3 aspect screen, for example, has an area of 96 square feet.

So, how much brighter would a projector need to be to look “as good” in a room with a 170” screen as it d'es in a room with a 120” screen? One valid response could be, “It d'esn’t matter – if the screens are in different rooms, nobody will ever compare them side-by-side. As long as the image on the larger screen is reasonably bright, they don’t have to be identical.” An equally valid response would be, “About twice as bright.” So where do these two answers leave the campus technologist, trying to evaluate their available options?

One option, which I’ll get out of the way first, is to double-stack two 3000-ANSI lumen projectors. This can work in certain limited applications, such as where you have a rear-projection area with plenty of space, or where there is a projection room in the back of a classroom where the projectors and their associated mountings can be hidden. This d'es not work as well where the projectors need super-wide throw lenses (which are not typically compatible with the lens-shift feature necessary to converge the pixels in a double-stack configuration) or where the projectors are mounted from the ceiling in an exposed fashion. The main benefits from double stacking are cost (two 3000-ANSI projectors often cost significantly less than a single 6000-ANSI projector) and redundancy – even if one projector completely fails, you still will have an image on the screen.

Evaluating projector choices in the 5000-6000 ANSI Lumen brightness range requires careful analysis for several reasons:

  1. These projectors are expensive. They typically cost 2-4 times what you are paying for 3000-ANSI lumen projectors.
  2. The rooms that they go into tend to be high-profile, high-use rooms. Performance, reliability, and maintainability are all important.
  3. Given that they are probably different from your campus-standard projector, there are cost-of-ownership issues in terms of maintenance and lamp replacement.
  4. There is a wide range of performance in regard to factors other than brightness, such as noise, lamp life, and contrast. Some of these directly affect the learning environment (distracting fan noise, accurate color representation), while others impact the bottom line (lamp replacement, warranty period).

Looking at the current available choices for XGA-native resolution projectors from the standpoint of the person who has to maintain them over their lifespan, there is one obvious criteria that needs to be given ample priority: number of lamps. While most projectors in this category have two lamps, there are some with only one. Having two lamps may be beneficial from a redundancy standpoint – but only if the projector is designed to operate with one lamp off (or blown), and not all 2-lamp projectors are designed this way. The immediate impact of a 2-lamp projector versus a single lamp unit is a doubling of the lamp replacement cost.

The Sanyo PLC-XP56 (and its Canon and Christie cousins) offers a single lamp and 5000 ANSI lumens of brightness. The main issue when comparing these projectors to the alternatives is of reading what is (and is not) printed on the specification sheet. For example, the specifications indicate that the brightness is 5000 ANSI lumens and the noise output is 35 dB in “Eco Mode.” D'es this mean that the unit will project 5000 lumens and emit 35 dB? Not at the same time, but try finding on the specification sheet how much noise it gives off at full-power mode, or how bright it is in “Eco-Mode.”

Likewise, comparing lamp life can be difficult. Sanyo d'esn’t rate the lamp life expectancy for their model, but Canon and Christie put theirs at 1500 hours. How long should the lamp last in “Eco-Mode?” No ratings are given.

Sony’s VPL-FX52 offers 6000 ANSI lumens (on “Lamp Mode High”) with a single lamp. With a noise output of 36 dB (high mode) and 34 dB (normal mode), it is reasonably quiet, especially for a projector of this brightness. What to look for, however, is the lamp life: while Sony provides this for some of their projectors, they do not disclose it for this one.

Epson’s PowerLite 8300i and Mitsubishi’s XL5980U ( both provide brightness in the mid-5000s, lamp life in the 1500-2000 range, and noise in the mid-30s (dB). Both should probably be considered if you need 5500 or fewer ANSI lumens and want to stick with a single-lamp projector.

There are a bunch of projectors that fall into a “2-lamp & loud” category: Eiki LC-X6A, Barco iQ G500, NEC GT5000, Panasonic PT-D5500U, and the Sanyo PLC-XF31. These probably should not be hanging 6 feet above a student’s head in a large classroom due to the 38-45 dB of fan noise they emit. For other applications, they’ll probably be fine if you don’t mind replacing two lamps instead of one each maintenance cycle.

The outlier from this 2-lamp group in terms of noise and lamp performance is Digital Projection dVision 30XG. Projecting 5500 ANSI at full-power, while emitting 35 dB of noise and with 2000 hours lamp life, it appears to represent a reasonable balance of performance characteristics.

Budget-conscious users can successfully cross the 5,000 lumen barrier – by reading the specifications carefully for what they say (and don’t say) and by asking tough questions of the vendor. There may not be a perfect balance of price and desired performance for your application, but by approaching the problem carefully, you can usually find a good fit.

Will Craig, CTS-D, is a consultant with Elert & Associates, a nationwide independent technology consulting firm working with college, university & K-12 institutions around the United States.

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