So you’ve been watching those constant price drops for large sized LCD and LED TVs and you’ve finally decided to take the plunge. New HDTV? Count me in!
But wait… how to choose one? Hmmm…
For the past few years, the way to compare LCD/LED TVs was to look at their contrast ratios. TVs bragged about their 1:10,000 contrast ratios, or 1:25,000, or whatever else ratio they got up their sleeves.
That battle’s long gone. I’ll tell you why it’s Refresh Rate that matters now.
LCD panels have kind of matured these days, so that we’re now at an age where most people can’t tell the difference in contrast ratios anymore. (Hint: If you want brighter whites though, go for LED TVs. Especially backlit LED TVs.)
So with contrast ratios a done deal now, what’s next? The answer is refresh rate. This is the number that comes with the Hertz or Hz sign on those hype stickers on the TV sets.
Why Hertz matters
So what’s with this Hertz thing anyway?
Your typical LCD or LED TV will have a 60 Hertz refresh rate. Translation: the image on the TV screen gets refreshed 60 times a second. I won’t bore you with the technical details, but suffice to say that it makes for passable movements onscreen. It’s your typical moving picture experience.
Why 60? Because power outlets in the USA and many parts of the world (including former colony the Philippines) run on 60 hertz AC power. So when TV sets were originally designed, they were built around the power supply. Old fashioned picture tube TV sets therefore “painted” their images 30 times a second twice over (the picture tube beam makes two passes every second). This is called the NTSC standard (fondly called “Never The Same Color” back in the day).
In European countries and former colonies, however, the power supply was 50 hertz. So this led to TV sets that refreshed 50 times a second, under what is called the PAL/SECAM standard. This is why back in the days of picture tube TV sets, you can’t use a European TV set in America and vice versa.
The point of all this is that once upon a time, our TVs were refreshed at 60 times a second, and this became the industry standard that LCD TVs followed.
But it can be made better. And this is where higher refresh rates matter. Why? Because higher refresh rates will make for smoother movements onscreen.
So what I’m saying is that today, the battlefield has already moved from contrast ratio to smoothness of movement. And it’s all about the hertz.
Next time you shop for a TV, compare the fluidness of the movement. If the motion of the action onscreen feels unusually “real,” then chances are that you are watching a TV set with a 120Hz refresh rate. This is when you’ll appreciate why hertz matters.
While your typical 60 hertz TV set will do fairly well, a 120 hertz TV set is refreshing the image twice over. And this allows movements onscreen to look much smoother. Cars fly by like they were real, and explosions bloom in vivid detail.
So by that argument, I should get a plasma TV with a 600Hz rate?
Quick Answer: NO.
Here’s why. Plasma TVs are a different technology versus that of LCD and LED TVs. So when plasma TVs talk about refresh rates, it isn’t the same refresh rates that LCD/LED TVs talk about.
With LCD/LED TVs, refresh rate is all about the speed by which images are shown onscreen.
But with plasma TVs, it’s all about the length of time that individual plasma pixels are on or off. Note that unlike LCD panels which can have varying shades of colors, plasma pixels are only on or off. So in order to simulate shades of color, it’s all about how long a plasma pixel stays on. Leave it on for just a fraction of a second and the color is less intense than if it was fully on. And so, the greater the hertz rate, the more the range of colors that a plasma TV can display.
So it’s apples versus oranges, so to speak. Hertz on plasma is all about color range.
Of course it’s all in the eyes
In the end, it will all depend on how you actually like a TV’s images. The proof is in the viewing, as they say. So the next time you visit an appliance store, do compare the images on sets with 60 and 120 hertz refresh rates (or more) and see if you like the difference. I’m sure you’ll see the difference, but then see if that difference is worth the price gap.
You must be logged in to post a comment.