What you need to know when buying a HDTV

I wrote this a year ago and it still holds true today. The only change is that there is a third class of HDTVs- LED-backlit LCD. It is a LCD display that uses LED backlighting rather than using fluorescent lights used in traditional LCD TVs.Ok folks, here are the things you should know when considering buying a HDTV. I know that there will be some debate, but these are the things that I feel are most important and will give you the piece of mind that you made the right choice. So, let's get to it.

The SPECS game is worthless. This is where the vendors use questionable techniques, inability to agree with each other and in some cases dirty tricks. I suggest that you don't use them. But, if you do then follow this simple rule- only compare models from the same brand. There is no real way to tell if Panasonic's 15,000:1 contrast ratio is better than Sony's 25,000:1. But, you can be pretty sure that Panasonic's 15,000:1 is better than Panasonic's 9,000:1. Also don't fall for specific SPECS such as Response Time, Viewing Angle, and Dynamic Contrast.

Lets look at each.

Response Time-Response time supposedly represents how long it takes for a pixel to change from one color to another and they use that number as a gauge of how quickly a set can respond to fast moving images. the problem for you as a consumer is that some manufactures' measure that time as the time it takes for a pixel to change from black to white to black while others use gray to gray. ( Again no consistency across manufactures )

Dynamic contrast is another inconsistent measurement. Vendors almost always inflate this number and they don't measure it in the same way so it is impossible to measure it across brands. generally speaking, plasma TV's have the highest contrast ratio followed by the new LED TV's.

Viewing angle-you should check this out in person. Since there is alot of flexibility in the definition of what a good picture is just go to the store and check it out. The vendors are claiming 176 degrees before picture quality diminishes but, if you go to the store and actual check it out I'm quite confident that you will be displease with the picture quality long before 176 degrees.

Features that do matter- Refresh Rates and HDMI. These are features that the vendors can't fudge. Either the model you are looking at support a 120Hz refresh rate or it doesn't. Why is the refresh rate so important ? Here is why- Normal TV's refresh what is on the screen at 60Hz or 60 times a second. Most HDTV's are capable of refreshing twice that. There is a number of advantages to the 120Hz mode. First, it can smooth out fast motion in sporting or other fast moving live events. TVs capable of the 120Hz mode consistently sport faster response times. Secondly, and for me the most important advantage of the 120Hz mode, is that it perfectly matches up with the speed of movies which are recorded at 24fps. On regular TVs, 3:2 pull down is the process that translates the 24fps into 60fps. A 120Hz TV can display each frame five times. You will find HDTVs in 60" or high sporting a 240Hz refresh mode, Although it is nice to have, I haven't been able to discern any visual difference in looking at live sporting events in 120Hz or 240Hz mode.

HDMI (High Definition Interface) is the first only only industry-supported, uncompressed, all digital audio/video interface. HDMI supports standard, enhanced, or high definition video plus multi channel digital audio on a single cable. The most important piece of information to remember about HDMI is that all video/audio signals from your components, for example, a PS3 is uncompressed. Anytime you compress video/audio you introduce compression artifacts.

You see it in all the ads and hype 1080p. Its gotten cheaper over the years and it is hard to find a 40" or bigger LCD TV without it. Although it is nice I believe that 1080p isn't always a necessity when considering a HDTV. Let me explain my reasoning. First and foremost, you should consider the room size before you consider stepping up to 1080p. There is a wonderful piece of research by Carlton Bale that illustrating where you can tell the difference between the various HD resolutions click here. For example say you are sitting more than 10 feet away from a 40"LCD, based on the chart you will not see much of a difference between 1080p and 720p. Also, unless you are hooking up a game console or a Blu-ray player it is unlikeley that you have a source that does 1080p. Cable and Satellite providers recompress the video and audio they're broadcasting to you. Bottom line- don't be afraid of buying a good 42" 720p HDTV, especially if you are not hooking up a game console or Blu-ray player.

Another bug-a-boo which must be fully understood, is that when you go to a store to look at HDTVs, the in-store environment can make it very difficult to tell how a HDTV performs. The display models you see on the floor are usually set to super-high contrast and brightness settings, the lighting offten will not resemble the lighting environment at home. For this reason alone, I recommend to all my clients to have their HDTV professionally calibrated when they get the TV home. There are color calibrators on the market for under $500. So, you say what can I do in the in-store environment. Follow these simply rules: Change the picture setting to the movie mode or in some cases the middle picture mode, since it typically uses lower, more realistic brightness and contrast levels. Bring your own demo material, take a DVD disc you are familiar with, it will help you see itf the scene looks the way it should. Be on the lookout for shadow detail. LCD TVs often will have some difficulty in reproducing subtle shadings in dark scenes.

Plasma vs LCD. Ok, I know you will find a differing opinion on this subject. I for one prefer Plasma over LCD. (that was written last year and I must say that after seeing some of the newer LED TVs I'm leaning towards the LED display). Plasma TVs display deeper blacks than LCDs, allowing for much better contrast levels and that deliver a picture quality I find second to none. I must be upfront and mention the big caveat in the fore-mentioned statement, the room needs to be dark. Better put, Plasma TVs should not be installed in sun drenched rooms. LCDs preform better in that environment.

I hope this helps you evaluate and find the right HDTV for you. If you consider the information I have given you in this article you should be happy with your purchase. And, I suggest that when you get the TV home and installed make sure you get the TV professionally calibrated.