Brightness is the other significant component in the quality equation. Light disperses over distance: The farther your projector will be from the screen, and the larger the image you are trying to project, the brighter the projector you'll want to be using.

The ideal is a projector bright enough to throw visuals that are sharp and easy to see in normal ambient lighting conditions - in other words, your audience can see your visuals without having to have the lights turned down to improve brightness and contrast.

ANSI lumens provide a common scale for determining a projector's brightness. Generally speaking, 1,000 lumens is a minimum for leaving the lights up in a small meeting room - but 2,000 or higher is desirable in smaller presentation venues, and 3,500 and up is a good threshold for larger rooms, or if you're projecting visuals where fine detail is involved.

Don't rely solely on the lumens rating in specifying a projector. The same image projected from two projectors with the same lumens rating can appear markedly different depending on the type of lamp involved (UHP, UHE, metal halide or halogen). Projection lamps dim with age, so brightness declines over the life of the bulb. At 1,000 hours, a lamp rated for 2,000 hours of use might be projecting an image about half as bright as when it was new. At 2,000 hours, newer evolutions of the technology (UHP and UHE) will still retain about 80 percent of their brightness.

TRADE SECRET:
Many projectors have a "life" counter in their Setup menu that will tell you how many operating hours are on the bulb currently in use. While you're checking that, make sure there's a spare lamp available in case something unforeseen happens to the current occupant of the bulb socket during your presentation.

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