HDTV Tech

Today, 3D has become a de facto feature on almost every higher-end TV and even many projectors, and it continues to make headlines. But the biggest news to come out of the CEDIA Expo trade show this past September wasn’t of the three-dimensional variety. The news that took many attendees by surprise was 4K.

It may not sound very exciting, but Advanced Super In-Plane Switching (AS-IPS) is a pretty neat technology. It is yet another improvement in the world of LCD, brought to you by Hitachi, as well as Panasonic and Toshiba.

In the November 2007 issue, I tested 74 HDTVs for their ability to process 1080i signals, the highest resolution standard found on most of the broadcast and cable networks. A number of the remaining HDTVs to be introduced in 2007 arrived too late for our November issue. We decided to follow up with some more displays. Due to space constraints, this article will refer to previous articles more than we normally do. On the bright side, all the articles mentioned (including the November 2007 test) are available on this site.

By now, most home theater fans have undoubtedly grown used to seeing letterbox bars on many movies they watch. In today’s high-definition era, any content with an aspect ratio that’s greater than a 16:9 (a.k.a. 1.78:1) HDTV screen must be presented with black bars on the top and bottom of the frame. Blu-ray viewers have many examples of this. Approximately half of all modern theatrical films are photographed in the scope aspect ratio of 2.40:1. Iron Man, Tropic Thunder, and Wall-E fall into that category. Scope photography is sometimes referred to as 2.35:1 for reasons that are too complicated to explain in detail here. Just know that 2.40:1 is technically correct, although many people in the industry continue to use the term 2.35:1 interchangeably. At the other extreme, material narrower than 16:9 (classics like Casablanca and The Adventures of Robin Hood are 1.37:1) will have pillarbox bars on the sides. In the middle, movies composed for 1.85:1 (such as the The Sixth Sense, Hellboy, or Knocked Up) nearly fill an HDTV.

There’s more that goes into making a good display than accurate color, but it’s certainly one of the biggies. Color in a video display may seem like a relatively simple subject, but it’s not. In this Gear Works, I’ll outline the two most important factors in assessing and measuring the color accuracy of the HDTVs we review—color tracking and color gamut. I’ll also show you how we present this in the HT Labs Measures graphics that accompany our reviews. This article will shed some light on what these important measurements tell us about the color accuracy of the displays we test here at Home Theater.