Buying a Projector?
Ask these 10 essential questions
1. What's my budget?
Even Bill Gates asks the price sometimes; I know I do. Before you can determine an acceptable price range for your projector, you first need to determine what your budget is then stick to it.
A realistic budget helps, of course. You should be able to find plenty of SVGA projectors for about $4,000 and XGA projectors for $7,000. The latest lightweight ultraportables sell for a little more, but if you're willing to wait, they, too, will drop in price. It almost goes without saying that the more performance, features or brightness you want, the more you'll have to pay.
But regardless of your budget, it's likely there is a projector out there for you, so explore all of the options. Even if your budget is frighteningly low, it's often possible to find close-out models and refurbished rental-return units at a considerable discount. Some of these deals even come with decent warranties.
2. What will I use the projector for?
I know this sounds like an obvious question, but you'd be surprised how many people call me up for projector-buying advice who haven't bothered to think about it.
Are you going to be carrying it around every day? If so, weight is a very important consideration. But if you're not going to lug it around much, weight isn't as crucial an issue. For the same price or lower, a sturdier, heavier (and more fully featured) projector will work perfectly well. Once you start looking at projectors, you'll also be amazed how many extra features you can get with just a few extra pounds.
It's also important to determine where you will place the projector and what size screen you're going to use. This is important because there is no standard for projector placement and image size. If you line up several different, similarly priced projectors and turn them on, you'll see a variety of image sizes (and elevations) at the same height and distance to the screen. Some projectors have been designed to work close to the screen and some come with a wide-ranging zoom lens that gives you the option of being close to the screen or farther away.
Then there's the little issue of keystoning, the wider-on-top image distortion caused by projecting at an angle the projector wasn't designed for. Some projectors have "keystone correction," a feature that allows you to adjust the image to compensate for the distortion others don't.
3. How bright should my projector be?
Everyone wants to have the brightest image possible, I suppose it's only natural.
The catch is that a projector's perceived brightness depends largely on the size of the image it is projecting. A 600-lumen projector will look great on a 60-inch-diagonal screen, but the same projector will look fairly dim if you're using it to fill a 120-inch-diagonal screen, which has four times the area.
Projector manufacturers like to brag that even their smallest projectors can be used to fill a 300-inch screen, but to do that effectively you need closer to 6,000 lumens of brightness, or 10 times the light output of the average ultraportable.
In general, ultraportable projectors shoot from 400 to 1,000 ANSI lumens, heavier conference-room projectors from 1,000 to 2,000 lumens and large-venue projectors anywhere from 2,500 to 10,000 lumens.
But remember, manufacturers are prone to fib about brightness, the way most people lie about their body weight or annual income. There can be hundreds of lumens of difference between the brightness a manufacturer claims for the model line and the actual brightness of individual projectors. Try to buy a projector from a reputable, trustworthy salesperson who will be honest with you about these discrepancies.
4. What are the lamp's life and replacement cost?
While you're asking about lumens, also ask about the projector's lamp. Unless you're in the market for a CRT projector, the lamp is your projector's light source and, like any light bulb, lamps burn out. Expensive replacement bulbs are one of the hidden costs of owning a projector, so how often you'll need to replace them should be an important factor in your buying decision.
Indeed, it is sometimes cheaper in the long run to buy a more expensive projector with a longer lamp life than to buy a less expensive projector that burns bulbs faster. If you need your projector to operate at the peak of its capabilities to light up a large screen under harsh ambient lighting, for instance you could end up buying a lot of replacement lamps to keep the projector operating at its optimal level.
To educate yourself, ask how many hours of use you should expect to get from the projector's lamp. Ask how bright the projector will be after the lamp has been run for several hundred hours (it often goes down dramatically), and ask how bright it will be when the lamp is approaching the end of its life.
Also ask about the lamp's rated power in watts. If you're trying to decide between two projectors with equal or similar brightness, but one produces its light with a 500-watt lamp and the other uses only a 100-watt lamp, you should choose the 100-watt-lamp projector for a variety of reasons. Not only will it stay bright longer, produce less heat and require a less noisy cooling fan, it will use less energy and last longer because it is inherently more efficient.
5. What's the resolution?
As I explained earlier, a key factor in a projector's price is its resolution: VGA (480 x 640), SVGA (800 x 600), XGA (1,024 x 768), SXGA (1,280 x 1,024) or higher. Know what you need before you go shopping.
If you're only going to use your projector for simple, bulleted-text PowerPoint slides, you probably don't need the highest resolution. SVGA or even VGA (if you can find it) may work fine. But if you're going to be presenting a circuit design you created on a workstation, you'll need the highest resolution possible: SXGA or better.
Ask your salesperson what the projector's native resolution is. Most new projectors can resize (shrink or expand) a computer's image to fit the projector's fixed matrix of pixels. If this resizing is done skillfully, it is hard to tell exactly what the projector's native resolution is with most images. Some SVGA projectors can make an XGA or even SXGA signal look decent. But if you try to project a detailed CAD drawing on that same SVGA projector in full 1,280 x 1,024 resolution, you'll see that some of the lines are missing and other lines are fuzzy. These resizing artifacts will not exist if you project the same image with a projector that has a native SXGA resolution.
6. What are the lens specifications?
Besides knowing whether you need a motorized-zoom lens (only a few projectors are zoom-less these days), what else is there to know? Plenty. Anyone who has ever shopped for an SLR camera knows the importance of an f-stop or f-number the smaller the number, the more light transmitted (brighter the image).
Besides the zoom range (the amount of change you can get in image size), look for a lens in which the f-number doesn't change much with the zoom setting. This will ensure that your projector produces a bright, high-contrast image no matter how you position a zoom lens.
If you're shopping for a conference-room unit and weight is not important, look for a lens with all-glass elements. To save weight, many projector lenses are made of plastic or a plastic composite, but the onscreen image from a good glass lens cannot be beaten; it will be sharp and in focus, even in the corners.
In the conference-room arena, another important thing to consider is an optional projection lens. Many manufacturers are starting to offer a range of lens options that allow their projectors much greater flexibility to "throw" images far and wide. If conference-room flexibility is important, ask about optional lenses. If the manufacturer doesn't provide one, a third-party lens company such as Buhl Optical Co. probably will.
7. What about contrast and color saturation?
Color and contrast are a bit like Mom and apple pie: Everyone loves them, but few people can say exactly why.
Regarding contrast, most projectors have plenty for the vast majority of applications. Unless you're very picky about video quality, which looks better with lower black levels, contrast won't be much of an issue.
Surprisingly, color or color saturation is rarely defined with any specificity by people in the projector industry. If great color is what you're after, though, it's not difficult to make a few accurate generalizations.
Today, a three-panel LCD projector or a three-chip DLP projector gives the best color saturation. One-panel-LCD and one-chip-DLP units generally provide less color saturation than three-chip units, and their reds and blues are sometimes weak. The big light-valve projectors are close behind the LCD and DLP units but have more color variation across their images. CRT projectors deliver a level of color saturation somewhere between the three-panel and one-panel projectors.
For general purposes, however, most projectors produce acceptable colors. If you like what you see, there's no need to quibble. Just be sure to check the color intensity under different lighting conditions to see how the projector performs in the real world.
8. How much does it weigh and what else can it do?
Such a wide range of features exist in the projector world that I usually have to make a chart to compare two projectors' features. At a minimum, find out how many inputs, outputs and onboard speakers the projector has. Add to that list any of the projector's other capabilities, such as motorized zoom, focus and lens shift.
Other features I like to see are easily operated elevator feet, comfortable and sturdy carrying handles, easy-to-use onscreen menus and, for ultraportables and portables, a lightweight carrying case.
If weight is important to you, don't just find out how much the projector itself weighs ask about the total carrying weight of the unit, case and accessories. You'd be surprised how quickly different projectors' carrying weights are equalized when the required cables and accessories are added. In addition to the carrying case's weight, the signal cables and remote-control unit usually add about two pounds to a projector's overall heft.
9. What sort of warranty and service can I expect?
Let's say you've ponied up the cash for your new projector. Now, suppose you're out in the field and the thing suddenly stops working. What if the lamp blows up or some circuitry fries? What do you do? That's when your service warranty kicks in and you'd better have one.
Fortunately, because projectors' overall quality is now so good, many manufacturers are competing to provide the best possible warranty and service options. Some manufacturers now even offer free overnight replacement of a dead unit, no questions asked. If you're a road warrior, that's the kind of service you want.
Otherwise, one-, two- and three-year warranties are the norm. Still, a wide range of service plans exist to choose from, depending on the manufacturer and dealer, so read the fine print carefully. In particular, find out how long the lamp is covered under warranty; sometimes it's only for a few months.
As always, get everything in writing, and keep a projector file so when you need to use that warranty, you know where it is.
10. Can I see a demonstration?
Nothing will inform you more about a projector than seeing it perform. So ask for a demo or better yet, a number of demos.
To make sure that I see a full range of image-quality parameters, I usually bring a disk of professional test patterns and images to a demo. Sonera Technologies' DisplayMate (www.sonera.com) is one of my favorites, but there are a number of others on the market. If a professional test pattern isn't available, just slip a disk of your favorite images into a computer and see what that new projector can do.
If you're trying to decide between two competing models, ask your salesperson to arrange a "shoot-out," so you can view both projectors with the same image at the same time. In my experience, practically every projector looks good by itself; you won't see its warts until you make a direct comparison.
* William Bohannon