what's the difference between 60 hz and 120 hz when it comes to led/lcd tv's?

Hz hertz. It's the refresh rate if each pixel. The higher the rate the less jittery and more smoothe the picture looks. But don't be fooled by tvs offering more then 120 hz because the human eye won't tell the difference so don't spend extra money on 240hz tvs. Only LCD tv apply. Plasmas never suffered from jitter

The best answer is a complete croc. The human eye can't see? Complete and utter bs.

The human eye doesn't see frames, it sees light. But the human eye can EASILY see 120hz and FAR BEYOND that.

For example, the USAF did a study with its pilots by flashing a picture at them for 1/220th of a second. This would correspond to 1 frame out of 220 in a second. I.E. If say you had a 220hz signal being shown and something was flashed for 1 frame.

Then they asked them what they saw.

They were able to not only 'see' it, but be able to IDENTIFY what TYPE of plane it was.

This also means you can easily see something far faster then that, because there's seeing something, and then there's being able to see it long enough to recognize and identify it.

It's also been shown the human eye can notice light/dark differences at over 600hz.

So the guy who gave advice 4 years ago was full of it.

Maybe his problem was that he didn't realize most 240hz sets aren't true 240hz input, but use motion interpolation. Which 'guesses' what an in-between frame(s) would look like.

Most sets are 60hz. They just use the motion interpolation for 120 or 240. They can also do what the guy above said and flash each frame multiple times.

But there are 120hz monitors out there, and even beyond.

Hard to find HDTV's with true 120, but the Seiki 39/50 4ktv does have true 120hz at 1080p. (I've gotten mine to do 136hz).

due to response time from 2ms to 8 ms * depends of models / maker * from LCD display , there must be so call motion blur.

motion blur can be easily noticeable from big screen TV - 32 inc and above . any " fast action moving image " eg , sports movies soccer / games cause motion blur , it make our eye very uncomfortable.

however not all human eye noticeable the motion blur, many consumer's watch sports movies from very low end big screen LCD TV ( 60 HZ 7ms response time models ) and never FEELS uncomfortable .

but some people with sensitive eye, even cannot accept such ' blur ' from hi end LCD/LED TV with 120HZ 4ms response time models and go only for Plasma -- 100 % with out motion blur 0.01 response time 600 HZ refresh rate .

motion blur can never ' cut off ', but fast refresh rate double from standard 60 HZ to 120 HZ / 240 HZ is to " hide away ' the motion blur .just to make our eye comfortable and it work well. as 120 HZ models always use fast response time display panel. standard 60 HZ models always 5ms to 6.5 ms even some are 7/8 ms response time.

120 HZ models usually is 4ms response time even new hi end models as only 2 ms . keep in mind , 1ms make great difference to provide smooth pictures. ( like F1, just 1 sec faster become champion )

i should said , if you watch sports movies / games . 120 HZ models really great compare to standard 60 HZ models.

the easy way to tell, watch soccer , and look at the ' ball ' is great difference between 60 / 120 HZ models.

if you are looking for new 3D LED TV ( LCD-LED BACK LIGHT ) ?

as 3D TV need fast refresh rate and fast response time in order to display more effect 3D image. i should said , all 3D LED TV on the market are excellence to standard 2D movies , because all are fast refresh rare + lower as 2ms response time. i don't think any 3D LED TV with standard 60 HZ refresh rate also higher than 4ms response time.