Avi Greengart is the Research Director for Consumer Devices at Current Analysis (Mobile Phones, Connected Devices, and Digital Home). He also regularly writes for Slashgear, sporadically blogs at Home Theater View and Tweets far too often as @greengartAvi's expertise lies in understanding consumer electronics marketing, consumer behavior, and technology adoption patterns: where new technologies meet the mass market. 



Avi Greengart is an expert on the convergence of technology and entertainment: video, audio, computing, and wireless, how these are coming together, and what's likely to survive long enough to make a difference in your life.

Column #15                                                                       December 2, 2001

PowerPoint or Peckinpath: Business Projectors For Home Theater

Question: I use a projector at work for PowerPoint presentations. Could I use this projector at home for watching movies on a really big screen?

AskAvi responds:

In most cases, you could. The question is whether you would want to.

The biggest part of the theater experience is the big screen. When an image takes up more than 30% of your view, your brain starts visually interpreting the image as “real.” When the image takes up the majority of your view, your brain really starts playing tricks on you – for example, at an IMAX theater, you might feel that you are on the rollercoaster or under the water with the actors on screen. So a big image is critical for big impact. Certainly, if you want to project a large image, and your data projector can display video (most can), you can have an extremely enjoyable experience. Just bring the projector home, hook up your DVD player, turn out the lights, and press “play.”

The great thing about business projectors is that business people buy them to project things. There are a lot of business people out there, and it doesn’t take too much handholding to sell a business projector, so the prices have dropped accordingly. Business projectors that can throw a bright, colorful 100” image start at only $1,500 – much less than a decent big screen TV that can display an image only half the size. Plus, the projector is tiny, portable, and digital, so the image is always converged and stable. What’s not to like?

Well… if you’re designing a home theater incorporating a projector, there are good reasons to go with a projector designed specifically for home theater. Most digital business projectors:


Don’t have the adjustments needed to get the best color, black level, and picture


Don’t have the circuitry required to produce the best looking motion with interlaced sources


Are intended for 4:3 (square) presentations, and may not provide a complete range of controls for dealing with 16:9 (rectangular) program material, such as widescreen movies


May be optimized for maximum brightness, which allows presenting with the lights on, but can cause eyestrain in a darkened theater


May not be optimized for maximum contrast, which provides ‘black’ blacks (as opposed to ‘dark grey’ blacks) and the best image quality


May be based on technologies with significant video limitations:

For instance, with many LCD business projectors, everything looks like you’re looking at it through a screen door. LCD home theater projectors may have more pixels, staggered pixels, or oddly shaped pixels, all of which mitigate or eliminate the “screen door effect.”


With many DLP business projectors, there is the dreaded “rainbow effect,” where fast moving objects and bright objects on dark backgrounds appear to have rainbows following them around. Exact statistics are hard to verify, but the estimate is that 10% of people can see them, and a few of those folks get headaches from them. Newer DLP home theater projectors use quad-speed six-segment color wheels, which mitigate or eliminate the problem.


Digital home theater projectors cost between $3,000 and $15,000. And, if you’re knowledgeable enough (or use the collective expertise of the folks on http://www.avsforum.com), there are ways of getting the most out of certain business projectors, and ending up with an image comparable to home theater projectors costing – literally – ten times as much. If home theater is your hobby, using one of these specific business projectors is certainly the most economical route to go, and researching / buying / configuring it can be great fun. For specific recommendations, check out http://www.projectorcentral.com.

But if you want a knowledgeable sales person to help determine your needs, demonstrate the projector with video, and offer installation services, you should stick with home theater projectors sold by home theater dealers. I cannot underestimate the corollary to  this: if the home theater store you go to isn’t providing expert advice, don’t buy from them – expertise is a large part of what you’re paying for when you buy home theater-specific gear.

Oh, One More Thing...

There is one other option to consider, directly related to the digital business projectors we’ve been talking about: used CRTs. Projectors using traditional cathode ray tubes (the same technology in most big screen TVs) offer near perfect color and truly black blacks; many models using 9” CRTs can resolve full HDTV. They are extremely expensive ($10,000 – 60,000), but as industrial users are switching to digital projectors in droves, they’re dumping their used CRTs. You can find truly incredible deals on lightly used models for $3000 – 5000. However, a CRT is large, heavy, requires professional installation, requires professional setup, and requires regular maintenance (at least every six months). They are also not appropriate for all rooms: CRTs tend not to be very bright. This means you’ll need total control of all light in the room, and you can’t use them on screens more than five or six wide.


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© 2001, 2002 Avi Greengart