Projector Brightness and Contrast

Projecting high quality images

Once you have a fairly clear idea what you intend to use your projection system for, you’ll want to evaluate the potential image quality of different projectors. To make that kind of judgment, it’s necessary to understand the terminology used to discuss projector performance and output. This includes brightness and contrast as well as resolution and aspect ratio.

Brightness

Larger projection systems tend to be brighter than smaller projectors, a feature measured in ANSI lumens. Determining how bright a machine you need depends on how large your space is and how much ambient light will be in the projection room. If you need to have some lights on to interact with a larger audience that’s watching your presentation you’ll want a brighter projector, maybe 2000 or 3000 lumens. Conversely, if you plan to watch movies in a darkened home theater, you can get away with 1000 or slightly less (which covers most models).

Lumen counts are less a precise measurement than a general guideline, so don’t get hung up on small brightness differences between different models - and of course, the more lumens you have, the more you pay. Brightness measures also differ between video and data projection, with the figure for data coming out a little higher, so it’s generally data brightness that you’ll find listed in the projector’s specs.

Uniformity of brightness matters as well, since you want the projected image to be equally bright across the entire screen with no dull or darkened patches.

Contrast ratio

A higher contrast ratio indicates a projector’s ability to distinguish well between white and black, thereby producing a better defined picture. For example, DLP (digital light processing) projectors tend to have a higher contrast ratio than LCD (liquid crystal display) projection systems, but what you gain in black and white contrast you may lose in color reproduction. There are two different contrast ratio measurements - full on/full off and ANSI - that produce different results, so when you’re comparing projector models, make sure you’re looking at the same type of ratio for both.

You can compare all the lumen output numbers and contrast ratios you want, but it’s important to understand as many performance measures as possible to make an informed choice. Your local electronic stores won’t have many projector models available for demonstration, so the more you know going into a purchase, the happier you’ll be with what you get.