What Are Lumens in Projectors?
There are a number of different statistics that distinguish between projectors. While most people know what a projector's resolution is or what a given weight corresponds to, brightness ratings are a bit more opaque. However, understanding what a projector's lumen rating is, and what it means, is crucial to getting a good quality projected image, especially if your business requires you to present under a number of different conditions.
A lumen is a way of measuring light. Specifically, one lumen is one foot-candle of light falling on an area that is 12 inches on a side. A foot-candle is the amount of light that a candle outputs, as measured from one foot away. While one lumen is not very much light, a 100-watt incandescent light bulb puts out 1,600 lumens. Most business projectors put out at least 2,000 lumens of light, for comparison.
The number of lumens you need depends on two key things -- the size of the image you'll be projecting and the quantity of light in the room that will be competing with your projector's bulb. A 2,000-lumen projector will project a reasonably large image in a dark room, but if you want to keep the room bright, you might need 4,000-lumens of light output. When looking at projectors, don't be overly concerned by small differences. Due to the way that the human eye responds to light, a 2,100 lumen projector will not be significantly dimmer than a 2,300 lumen projector. In fact, the difference might not even be noticeable, although the difference between a 2,000 and a 3,000 lumen projector would be.
Manufacturers rate projectors on the basis of their maximum light output, but most projection modes actually reduce the amount of lumens the projector produces. To get as much brightness as possible out of your projector, turn off the lamp's eco mode, which cuts brightness to save power and extend the lamp's life. Go into the projector's image menu options and look for bright, vivid or conference room modes or something else along those likes. Natural, cinema and movie modes typically cut light output to increase a projector's performance on the dark scenes that are common in many movies and television shows.
In addition to lumens, manufacturers typically rate how different a projector's black looks from its white. The contrast ratio expresses this numerically. While a higher contrast ratio is better than a lower one, since there's no popular standard for rating contrast, it's possible for a 10,000-to-1 projector to actually outperform a 100,000-to-1 projector. Given normal business projection conditions and the type of material that usually gets projected, contrast ratios are much less important. Business projectors with contrast ratios measured in the hundreds, instead of the thousands, are usually more than adequate.
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