Projectors have long been used as a presentation tool in business and commercial entertainment, as well as in some very high-end home theater systems. However, projectors are becoming more available and affordable for the average consumer. If you are looking for one, here are a few things you need to take into consideration when looking for a projector for your business or home setup.
 

Entertainment or Business

The first thing you should take into consideration is the kind of content you want to show on the projector. Most business projectors are going to be used for a series of still images. If you're thinking about PowerPoint presentations and bar charts, then look in the business category. The home projector category is going to handle full motion video a lot better. If you want to play movies or games, make sure that your chosen projector can handle them.
 

Indoor vs. Outdoor

For the most part, if you want to use a projector outdoors, you need better quality all-round. You want the highest brightness, because you have less control over the ambient light, you want a high resolution and contrast ratio to boost your chances of a great picture, and you'll need a good screen or surface, and a decent sound system. One thing that might be more of a concern with an indoor projector is the noise it makes when operating, because that's going to be more noticeable in a small room, but beyond that a good outdoor projector will work well indoors too.
 

Reliability

You should check out the reviews for your prospective projectors carefully and make sure that you get a reliable model. You'll often see a lamp life rating, estimating the maximum hours you'll get before needing to replace the bulb. Obviously the higher that is, the better your chances of it lasting a longer time. You should also check out the cost of replacement bulbs and other parts, and get an idea of how easy it will be to maintain and repair, should you need to.
 

Portability

If you're planning to install your projector in a fixed position, for something like a home theater, then you don't really have to worry about portability at all. If you plan on traveling around, using it for business presentations, then you'll want something that's as small as possible.
 

Technical Specs

Zoom Range and Lens Shift

You should also consider the zoom range and lens shift capabilities carefully if you think you'll be using your projector in a variety of different environments, because these features will allow you to change the throw distance and alter the size and position of what you're projecting. Short throw projectors can be used in tight spaces and small rooms, whereas you'll need a long-throw lens if you want to use a projector in a theater or a very large space.
 

Aspect Ratio

The aspect ratio is the shape of the video image you are projecting and it's really all about the source material. A standard TV has an aspect ratio of 4:3, while HDTV, widescreen DVD, and Blu-Ray content is 16:9 or closer to it. Most modern projectors are 16:9.
 

Resolution

If you're using it for presentations then you can save money by going with a relatively low resolution, for example, SVGA is 800 x 600 pixels and will serve adequately. It really depends on the input material, so if you want to show HD movies and play games, you'll want a resolution of at least 1920 x 1080 pixels. If you're going to mix and match content, don't assume that a higher resolution projector will handle lower resolution content well, you really have to check. You can get 4K projectors, but you'll have to pay a premium, and there's a lack of 4K content right now.
 

Brightness

The brightness you need depends on the environment where you'll be using the projector. The darker the environment is, the lower the brightness you can get away with, but, as a general rule, the brighter your projector is, the better. You'll find that brightness is measured in lumens. A rating of 1,000 lumens or less might be perfectly adequate for a business projector, to be used in small, darkened rooms. For a movie projector in an environment with some ambient light you might want a rating of 5,000 lumens or more.
 

Contrast Ratio

This tells you the difference between the darkest and the brightest parts of the picture. The higher the contrast ratio, the better the picture will look. But lots of other factors, such as ambient light and screen quality will come into play here, so you can't rely on this spec alone.
 

The Right Technology

The vast majority of projectors on the market are going to be DLP (Digital Light Processing) or LCD (Liquid Crystal Display). DLP projectors have more moving parts and can suffer from the rainbow effect, because they use a spinning color wheel. LCD projectors are more reliable, but they tend to be a bit heavier. If you can afford to spend a bit more then another technology, called LCoS (Liquid Crystal on Silicone) will deliver the best quality images, but LCOS projectors tend to be comparatively heavy and expensive.
 

Connectivity

Projectors generally always have VGA ports, and you might find a range of other options, but if you're using it for games and movies then you'll want an HDMI port. A useful option for some people, especially in the business world, is a USB port that can handle a flash drive, because it's a handy way to carry a presentation.

Wi-Fi support can be very useful for streaming from all sorts of modern devices, so you don't have to plug in directly. For fixed projectors, an Ethernet port can be a really good idea, because it allows you to operate the projector online and it will be more reliable than Wi-Fi.