|NEC HT1100 DLP Video Projector|
|Home Theater Front Projectors DLP Projectors|
|Written by Michael Levy|
|Tuesday, 01 February 2005|
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The home theater universe has been expanding geometrically ever since the video projector broke onto the scene, and it took another leap when digital projectors became available. The newer models gave us much higher brightness, easy installation and lower cost, but lagged behind on black level and smoothness of image. Since black level is crucial to a quality home theater display, the CRT projector remained the system of choice for affluent, tech-savvy enthusiasts. However, in the past year, digital video technology has advanced to the point that I decided to look for a digital replacement for the venerable CRT projector that has been heart and soul of my living room AV system.
About 10 years ago, I designed a custom 100-inch rear-projection system for my living room, using a lenticular-freznel (rear-oriented) screen, driven by a DWIN HD-500 CRT projector. Thousands of hours of use now calls for a replacement. Searching through the products that might fit the specification I was looking for, my interest was piqued by the NEC HT1100 DLP projector. All of its features and specifications fit my needs, including an exceptionally high (reported) contrast ratio of 3,500 to 1. So I requested one for review to see how it would compare.
NEC is a major Japanese manufacturer, catering to both the professional and consumer electronics industry. They pioneered the video projection market with fine CRT projectors and were among the first to adapt the Texas Instruments DLP imaging system. They are a major OEM source of projectors to the industry and you have probably already unknowingly watched one of their projectors create a video image. Industry insiders have long known of NEC as a state of the art manufacturer and many more consumers are becoming aware of NEC Visual Systems as they expand in the market.
The HT1100 is the top of the line of NEC’s home theater projectors and sports the 1024 x 768 Texas instruments chip. It has several useful features that improve image quality and flexibility. It accepts digital sources through a DVI and all forms of analog input, from composite to component and RGB, all at any of the presently used scan rates for video and computer, up to and including HD. It has an iris to improve black level, a two-level bulb to extend bulb life, image shift in the 16 x 9 mode, a three-dimensional keystone adjustment for placement flexibility, and is even offered with an optional anamorphic lens. With a contrast ratio of 3,500 to 1, it is among the best projectors in producing the ultimate in image dynamics, even on dimly lit scenes. With fan noise levels under 30 dbf, it is among the quieter projectors made, and with a list price of only $3,495, it is on paper an exceptional buy.
In the early 1980s, some of the more advanced home entertainment installation companies started selling professional video projectors to movie enthusiasts, spawning a new industry. The concept broke into the marketplace in the late 1970s with the Henry Kloss-inspired Advent and then the Kloss Novabeam. It matured significantly when the custom installation industry started using projectors made for professional use by manufacturers like Sony, Barco, and NEC, and it took another leap when these were coupled with the first Faroudja line doublers. By using the Laserdisc as the video source, high-quality movie theater-sized images were finally available to the home.
These were CRT projectors using three tubes (red, green, and blue), each coupled to its own lens system and then carefully hand-converged onto the screen. They processed analog signals into an analog light stream that covered a screen by scanning it, going from left to right and then tracing down the entire image. Properly aligned and calibrated, the state of the art of CRT projection still delivers the state-of-the art in video imaging. There are, though, a few not so minor inconveniences. Not only do CRT projectors have a low light output that wears down with use, but they also need regular recalibration by a trained professional, which to this day keeps me working all over the New York/New Jersey area. State-of-the-art CRT projectors run over $30,000 and need to be coupled to a good video processor for the best image quality. The cost, complexity and trained personnel needed to maintain the system limited the number of dealers and consumers willing to take the plunge into the real home theater. Then along came digital projectors. They changed the entire landscape of home theater.
All digital projectors work similarly. They chop the image up into hundreds of thousands or millions of points. Each point represents a square section of the image and defines that section by color and brightness. These sections are called pixels that, when put together and viewed from an appropriate distance, meld into a contiguous image. Digital projectors use an imaging chip where transistors are coupled to each pixel which variably filters the light from a bulb in real time on a pixel by pixel basis to create an image. There are two ways to do this, pass through or reflective, and several systems have been developed to do it, but they are all variations of two designs: liquid crystal-based designs and digital micromirror-based designs. LCD-based chips are used as pass-through devices, where liquid crystals variably filter light directed from a bulb through them, and as reflective devices in designs such as LCOS or DILA, where liquid crystals variably reflect the light that hits them.
Micromirror designs are based on the lightning-fast physical movement of tiny mirrors on a chip to vary the light reflected from them. While I am aware of the development of other micromirror designs, the Texas Instruments DLP is the only micromirror imaging chip presently used in home theater projectors. It is now the basis of many video projectors from a wide array of manufacturers around the world.
With many manufacturers building competitive DLP-based products, there are many good products and it is hard for one to stand out qualitatively. It was the unique combination of design features of the NEC HT1100 that brought it to my attention, and they are the reasons why this product deserves a rave review. The high contrast ratio gives you image dynamics that were previously only available on CRT-based systems. The excellent lens system maintains color convergence and focus at the outer edges of the image. The bulb and iris control are used to maximize contrast ratio while matching light output to the installation, and the anamorphic lens option gives the projector HD level vertical resolution for 16 x 9 screens. These features give it the image quality that distinguishes it as the top performer in its class.
Also, the throw distance is less than on most digital projectors and much closer to those of CRTs. This is an important feature for anyone looking to replace the projector in an older CRT-based installation. Many of those installations used 4 x 3 screens. The 4 x 3 imaging chip in this projector matches them, although it can also be used for 16 by 9 screens. If the CRT projector it replaces used seven-inch tubes, as most did, the image quality will be greatly improved in most parameters. While the resolution of 1024 x 768 matches up well with the resolution of seven-inch CRTs, the light output and gray scale linearity are of another level completely. This projector is at least three times as bright and tracks gray scale better than any seven-inch CRT I have ever tested.
With all of these advantages, the CRT would seem outgunned, but even my venerable seven-inch CRT will outperform a DLP in some parameters. Digital projectors have a through-the-screen-door look if you are close enough to see the pixels and the pixelization of the image creates some artifacts when small details shimmer between two pixels. The CRT can look much more like a film projected image, and its absolute black level still outdoes any digital projector. If you can live with the low light output and the constant need for calibration, it is the more pleasing image. Having said this, remember that we are comparing a $12,000 projector with one that lists for only $3,495.