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Reflections: It is common that any light source at a complementary angle to your viewing-angle will result in glare - in particular if unit makes use of a screen-saver (a clear protective material that covers fragile screen itself). Glare can seriously degrade picture quality. The only real solution is to take away offending light source; in some cases situation can improve if one removes screen-saver – BUT remember that an unprotected screen is fragile and expensive to replace if damaged.
Floor-space: Any rear projection TV is literally a large box with a relatively large footprint. It is true that modern slim-type models do exist that are no more than 15 to 18 inches in depth - depending on screen size, yet cheaper CRT-based rear projection TV sets will stand out by at least 24 to even 30 inches to allow for necessary air-space between back of unit and wall.
Remember to take this into your calculations when planning your home theater as these two feet or so will have to be deducted from your available viewing distance.
Rear Projection TV Speakers: Forget all about them! Do not give any weighting to speaker system coming with your rear projection unit. You would not be using them as you will surely want to replace these with your dedicated home theater surround receiver speaker system. Do not even think of using build-in speakers of your rear television set as a center channel replacement. They will just interfere with sound coming out of your dedicated system - hence do not pay anything extra for this as you will surely be switching off your TV sound completely during a movie show.
Aspect ratios: We have already mentioned a number of limitations associated with rear projection television, yet in comparison, these are just minor issues. The real serious limitation with a rear projection TV is aspect ratio management.
This is trickiest of it all. Standard television comes only in 4:3 but rear projection TV systems come in both standard 4:3, and in 16:9 widescreen format. Once you choose your format however, you have to live with it - so once again, you have to choose wisely.
The 4:3 (1.33) or 16:9 (1.78) referred to as aspect ratio, is ratio of screen width with respect to height of image. All standard non-HDTV material is in 4:3 format while most modern films come in one of many widescreen formats - most common being 2.35, which in itself is not compatible with any of fixed aspect ratio TV systems.
There are various ways to deal with this - including:
- Image stretching to fill available screen.
- Use of black or gray bars on top and bottom of a 4:3 screen to show movie in its correct aspect ratio as originally filmed, but then effective film display will be smaller.
- Pan and scan editing where only most important portion of each frame is shown with rest being discarded.
Image stretching and horizontal bars can be extremely irritating while in 'pan and scan' you are giving up film information to have a full screen view. Worst of all, prolonged use of horizontal bars - especially black bars - leads to tube burn-out in CRT based systems at huge costs to you.
The incompatibility between screen formats renders decision on aspect ratio a rather complicated issue when choosing a rear projection TV set. Surely, there is no such dilemma with a front projection setup, but if your only way forward is rear projection, then you will have to choose wisely.
Here no one can help you in your decision - it is simply a matter of preference. The best way to decide on aspect ratio is by first determining what you will be viewing most.
Surely, there is a market for both front and rear projection TVs – it is all a question of knowing what are advantages and limitations of each with respect to your specific needs.
(c) 2004/2005 www.practical-home-theater-guide.com. All rights reserved.
Andrew Ghigo – editor & publisher of http://www.practical-home-theater-guide.com - a comprehensive home theater guide to home theater systems, product reviews and home theater design.
This article is an excerpt from a series of Projection TV Guides published on the same site.