[dmegatool]

I'll be looking for a new tv soon and I was wondering what's the deal with 60hz and 120hz ?

I understand the concept of 24frames and the 3:2 pull down and all. I'm just wondering if it's really worth it ? I got the feeling that most of the footage I'll be watching will be 30fps (broadscast tv including 24frames movies already converted to 30fps (29.97?)) and PS3 (60fps is good)

So 120hz will only make a difference on blu ray's ?

I've read some comments about 120hz feeling like watching handy cam stuff. Like it feels too "real". I'll go to the store tomorrow and I'll ask for a comparaison but I would like to get your thought on this. Cause we all know it, you guys are the best

[Gargoyle]

pffft, 120 Hz... Hasn't someone just released a 200Hz one?

You need 200Hz!!!

[Kickaha]

600Hz actually... Panasonic's new X1 series plasma panels.

[dmegatool]

yeah... thanks guys

[tomoe]

FWIW, from what I've gathered on avsforum.com and elsewhere, 120Hz is more a red herring (like contrast ratio) than anything actually useful when it comes to purchasing HDTVs.

[Maciej]

Why is contrast ratio a red herring, I wasn't aware of this fact. Got link?

But I have also heard that 120 didn't make much difference. However I have heard that playstation has developed some technology to utilze 120 for the purpose of 3d.

EDIT: I can't find where I read that ps3 thing tho, so I might be wrong about that.

[Eugene]

I found that when the 120Hz panels interpolate the intermediate frames that were never even there, images become unnaturally fluid or superfluid. Maybe it's just me, but it's hard to make something out of nothing.

[HezMah19]

120hz Screen is what allows NVIDIA to use 3D in many new games...was discussed here about a month ago I think.

Not so important for a TV set...very cool for gaming

NVIDIA Link

[Dorian Gray]

I haven't looked at the 120/240/etc. Hz thing much (or 100/200/etc. Hz in the markets with 50 Hz AC power), but it certainly has a silly ring to it. I certainly wouldn't want my TV inventing intermediate frames out of thin air. I wouldn't trust it to do a good job and I find nothing wrong with existing refresh rates.

Originally Posted by Maciej Why is contrast ratio a red herring, I wasn't aware of this fact. Got link?

Contrast is good, but dynamic contrast ratios (the most commonly reported values) are next to useless as they're not achievable on the screen at any one moment in time. Native contrast ratios over, say, 1000:1 (and probably lower) can't be seen in normal viewing conditions as ambient light reflects from the dark screen to greatly reduce the contrast. You'd need a pitch black room, with black walls, ceiling, etc. to see the super-high contrast ratios now quoted for some displays. Furthermore, LCDs only achieve their rated contrast when viewed perpendicularly. Non-IPS panels have ludicrous fall-off as you go away from that position, and even IPS panels fall to very low contrast ratios at 45 degrees off-centre. Plasmas have the best contrast but again, you'd need a totally dark room to see their full contrast.

[dmegatool]

Cool, I thought I was kinda crazy to think that 120hz was weird. Maybe it could be good with some nature documentaries.

[Eugene]

Originally Posted by dmegatool Cool, I thought I was kinda crazy to think that 120hz was weird. Maybe it could be good with some nature documentaries.

120Hz would be good if stuff were actually filmed at 120FPS.

[Maciej]

Originally Posted by Dorian Gray Contrast is good, but dynamic contrast ratios (the most commonly reported values) are next to useless as they're not achievable on the screen at any one moment in time. Native contrast ratios over, say, 1000:1 (and probably lower) can't be seen in normal viewing conditions as ambient light reflects from the dark screen to greatly reduce the contrast. You'd need a pitch black room, with black walls, ceiling, etc. to see the super-high contrast ratios now quoted for some displays. Furthermore, LCDs only achieve their rated contrast when viewed perpendicularly. Non-IPS panels have ludicrous fall-off as you go away from that position, and even IPS panels fall to very low contrast ratios at 45 degrees off-centre. Plasmas have the best contrast but again, you'd need a totally dark room to see their full contrast.

Ahh, well that I knew. Thanks!

[Kickaha]

Originally Posted by Eugene 120Hz would be good if stuff were actually filmed at 120FPS.

120Hz was chosen to allow native presentation of both 24fps (theatre film) and 30fps (television) produced content. There's no interpolation, as in production of new frames, necessary. Just show a content frame five times (for film) or four times (for television) during the 120 frames per second, and it ends up being shown at 'native' rate.

When film is transferred to television, there's an ongoing stuttering that happens to match the 60Hz of the display. Every odd frame is shown 3 times, every even frame is shown 2 times. This is called 3:2 pulldown. 120Hz eliminates the stuttering... provided the content is being streamed to it at the actual 24fps. Most Blu-Ray players do this, and some DVD players do as well, but only with content prepped for it.

Bottom line: *if* you have 24fps film content, and *if* you have a way of keeping it at 24fps, a 120Hz display will make it look more like the original intended presentation.

(Heh - watching a film right now that had a slow tracking shot of a static scene, and it showed off the stuttering beautifully. It just went bupbupbupbup instead of being a smooth pan.)

[dmegatool]

Leaving in about an hour for the store. I'll see what they got. I know there's a 50 month/no interest option on some model so I'll see. Kinda good option as I just bought my first house

[Eugene]

Originally Posted by Kickaha 120Hz was chosen to allow native presentation of both 24fps (theatre film) and 30fps (television) produced content. There's no interpolation, as in production of new frames, necessary. Just show a content frame five times (for film) or four times (for television) during the 120 frames per second, and it ends up being shown at 'native' rate.

Sure, but that's not what the commercialization of the technology has focused on. Motion interpolation is what most 120Hz HDTVs advertise and the results are spooky. Just go into the local Fry's or Best Buy and ask for a demo with any of the various branded motion enhancers turned on.

http://en.wikipedia.org/wiki/Motion_interpolation

On top of the frame interpolation, those sets tend to use sharpening to reduce the blur in the intermediate frames. Consequently they have to sharpen every other frame too... Yeah, you can turn it off, but it's on by default for a lot of those TVs.

[Kickaha]

Originally Posted by Eugene Sure, but that's not what the commercialization of the technology has focused on. Motion interpolation is what most 120Hz HDTVs advertise and the results are spooky. Just go into the local Fry's or Best Buy and ask for a demo with any of the various branded motion enhancers turned on. http://en.wikipedia.org/wiki/Motion_interpolation On top of the frame interpolation, those sets tend to use sharpening to reduce the blur in the intermediate frames. Consequently they have to sharpen every other frame too... Yeah, you can turn it off, but it's on by default for a lot of those TVs.

Sure, but those displays are almost always LCDs, where the interpolation is there to try and counteract the lower response time of the pixels when coupled with the lack of afterglow. It's adding the intermediate stages that you get 'for free' when you view something on a CRT or plasma.

Yeah, it's weird... the slower pixel change speed of LCDs coupled with the discrete on/off of the pixels means that it is *less* smooth looking than a CRT or plasma where the image blurs itself due to a more gradual state-change, but a faster response threshold.

Ie, they're using the 120Hz as an opportunity to try and overcome some of the shortcomings of LCDs for fast motion viewing. And I agree, it looks *odd*. That's a reason I'm looking at plasmas. But IMO, all display technologies could benefit from the more natural source rate matching possible with 120Hz. The 600Hz sub-field driving of the X1 panels is kinda wacky - they're claiming it gives them processing time slices that they didn't have before. It'll be interesting to see what comes of it.

[Matsu]

Yeah, just buy a plasma and don't worry about it. Minimum 480hz sub field drive, new ones with 600hz.

The most information you're going to get from any current HD source is 24p or 60i, however. So as long as the TV/sources pull down properly in the first instance (24p) or de-interlace properly in the latter (60i) you don't really have a problem even with 60hz. Some 120hz sets just flash the image faster, no interpolation, some, like Sony's Motionflow sets interpolate in-between frames- and this isn't as successful. Their new 240hz LCD is particularly odd. Despite the much faster refresh, motion appears quite awkward -- you have to see it on demo to understand. There's almost a very weird high frequency judder, any kind of motion just looks wrong.