Send us Feedback Buyer's Guide to Business Projectors: Key Features

Once you have your short list of projectors, you can narrow it further by checking the manufacturer's specifications and thinking about the following items:

Zoom lens: A zoom lens gives you the ability to set the projector at a convenient location, and adjust the projected image size. Many of the micro-portables have zoom lenses with limited range. A unit with a zoom factor of 1.2:1 will only let you adjust picture size by 20%. You can often move the projector a foot or two either way and accomplish the same adjustment. If you have a fixed screen size you are trying to fill, even a limited range zoom will make it easier to fine tune the image size to the screen. If you plan on projecting in many different environments, you may wish to invest in a projector with a more versatile zoom range, which will allow for more placement flexibility. Zoom lenses range from 1.1:1 up to 2.0:1 or more. The higher the number, the greater the zoom range.

Keystone Correction: In addition to the zoom lens feature, mobile users should consider the benefits of keystone correction. The keystone effect happens when you project an image from any angle other than straight onto the projection surface and results in an image that is not completely square. Most projectors now include a feature that corrects vertical keystone, which occurs when you are projecting downward or upward. Others go a step further and provide additional correction for horizontal keystone, which occurs when you are projecting from either side of the screen. Keep in mind that applying keystone correction typically results in a slight loss of detail and sharpness, but it can be invaluable when your projector cannot be set up perfectly square with the screen

Contrast: Contrast is the ratio between the brightest and darkest areas of the image. Contrast ratios should be high (1500:1 or higher) to get the best video or photo image. For computer graphics and data presentation, 400:1 is usually ample. However, room light substantially impacts contrast ratios by rendering blacks less black. With moderate room lighting, a projector with 400:1 contrast and one with 1500:1 contrast will look almost identical, all other factors being equal. If you are using your projector in a room with a good deal of ambient light, lumen output will be more important than contrast. However, in a darkened room, contrast will become more important for accurate display of graphics and video.

Video Signal Standards: Most business projectors accept composite video, S-video, and computer/RGB signals as three types of signal transmission. Most projectors also recognize YPbPr/YCbCr component video as well. However, there are two all-digital standards known as DVI and HDMI. Many new computer video cards feature DVI or HDMI output, which allow the user to keep the signal in the digital domain and eliminate analog to digital conversions. If you are interested in optimizing video performance and you have a video source that offers DVI or HDMI output, check to see which of the projectors on your list possess a digital input. The spec sheet may say HDMI, DVI-I, or DVI-D.

Multiple Computer Ports: If you want to connect multiple computers or video sources to the projector simultaneously, you will need multiple input jacks to accommodate this. For example, you may want to connect a notebook computer and a desktop computer to support two consecutive presentations, or two different presenters. If your projector only has one computer source, you'll have to unplug the notebook and plug in the desktop between presentations. Check to make sure the projector has enough connections to support your typical use.