A chance to talk to FlatpanelsHD's reviewers.
By micksh
#5645
Thanks a lot for very detailed review!
One question - what viewing distance do you suggest so horizontal lines in 3D would not be noticeable? (you only had 47", right?)
By Rescue
#5646
Thank you for the detailed review..

Regarding the minimum distance for nondiscerning odd/even lines and 3D resolution battle...

If we consider an eye (left of right) as an image perception organ, which itself decodes the image, then a pair of eyes as two image perception organs, then it is true that 2 x 1920x1080 has to be the source of information.
But I'm not sure if by its own the eye as an organ is the image perception device and I'm thinking that the brain is the image perceptor.

Let's see and compare 3D active with 3D passive from the perspective of information quantity and resolution. In 3D active system, at each frame the monitor sends a 1920x1080 pixel information to the brain through one of the eyes, by blocking the other. In 3D passive system, at each frame the monitor sends 2 x 1920x540 pixel information to the brain by distributing these information in lines toward each eye. The resolution for the brain means the number of discernable pixels which is a matter of angle between tho adiacent discernable pixels. In both systems the angle between two adiacent discernable pixels is the same, so the details are the same.
But in 3D passive system there is a minimum distance limit where the visible lines are also discernable and it represents an additional information for the brain, which disturbs the clearness of the image as would be visible through a filmy layer. In my opinion this problem is not exactly as a resolution problem, but a problem of having a new unwanted information because the size of that details, I mean the line is exactly the size of the full hd pixel, which was designed to a limit where the pixel size is below the discernable size (Remember the origin of 1080 lines!) That's why moving closer to display the pixel size (and the line height) is getting discernable and causes an additional unwanted information to the brain.

If the distance between lines would be half of the pixel, then we wouldn't observe it so easy, so that the optimal distance from where we can watch the display would have much larger interval, I mean we could stay much closer to the display. Unfortunately halving the size of the line would mean doubling the resolution to 2080 lines. I guess those who designed 1080 lines HD standard, didn't thinked about 3D passive systems so that they sticked our best comfortable visibility distance to a very short interval (not too far but not too close). Also don't think that instead 1080 lines HD would have to be 2080 lines, but somewhere at ~1600. If we would have a 1600 lines HD system, I'm sure we would keep those watching interval more confortable in 3D passive systems too. Therefore I would expect some development in that direction.

So the trick with the current 3D passive system is that we should be keep relatively far from display, thus reducing our interval from where the HD details are discernable but those line does not get discerned by our brain. That's why the reviewers always mention this visibility distance problem!

All I would like to say is that in my opinion, the simplest resolution calculation per eye as a perception device by its own, here does not work and would not explain any phenomenons we see it. Therefore I am following this information quantity approach instead.
By micksh
#5647
I guess it's all similar to interlaced 2D video. For static pictures there is no difference between 1080i and 1080p. The difference becomes visible with motion and depends on viewing distance.
And I think deinterlacing algorithms are not applicable for passive 3D. Yes, the effect is a bit different. For passive 3D instead of comb on moving edges each eye sees only half of the lines and the effect depends on how brain combines images from both eyes. It may be subjective and may depend on person.
So, it is not exact analogy, but I think it simplifies understanding.

Still very curious about even rough distance estimation. I understand that at some point horizontal scan lines won't be noticeable but the picture may look a bit softer comparing to full 1080p. How does this point fall into THX recommended viewing distance range?
By sinistro
#5650
Chad B did mention on his review that on the 55lw5600 the threshold for him seeing those scan line was just a little more than 2M.

I guess that there is no difference between the 6 and the 5 series with this.
By blackbird
#5655
Thank you for the review, just two doubts. You talk about the "local dimming" function (which is not a real local dimming because of the edge LEDs), but i did not understand if you are using it when you say that black level is 0.08 cd/m2.
If not, could you tell me if the black level can be lowered when this function is activated?
When "local dimming" is active do you see any "columns of light" or haloes around bright objects on a dark background?
By powerboatnut
#5659
Been looking at the LW5600 and have read all entries here and on AVS forum. Trying to decide if I need to go to the 6500 at 240hz or if the 5600 at 120hz will be adequate. My kids and I are occasional FPS and driving gamers but most of the use of this tv will be sports, movies and some dopey shows like Idol that they watch with mom! Spoke to a tech at LG and it seems that all other items on the two sets are identical.....he suggested the 240hz since I mentioned alot of the reviews mentioned game lag.....he personally tends to slow down or eliminate processing on his sets since he says the motion looks too quick to him (due to the way tv has historically looked up to this point). He also mentioned that he thought that the passive 3D was going to be offered later in the year by LG in the plasma series. He did not have any info on price point but thought very soon these sets would be available....I have not seen any info that would support this but have to say the inky black and no lag of plasma mated with the passive 3D might be what I should be waiting for.

Any input on the 120hz vs. 240hz question?

Anyone else heard that the passive (to join the present actives they offer) might be coming out from LG in the plasmas?
By sinistro
#5662
So far I know any image procesing will add inputlag so on this isue the 100/120Hz will have less or at least the same inputlag as the 200/240Hz.
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By Rasmus Larsen
#5669
micksh wrote:Thanks a lot for very detailed review!
One question - what viewing distance do you suggest so horizontal lines in 3D would not be noticeable? (you only had 47", right?)
Sorry for the late answers, guys. We have many TVs at the moment so I will make this short.

Yes, we had the 47-inch model. I didn't see horizontal lines in 3D from typical viewing distance - only if I moved very close (something like 1-1,5 meters). So 2-2,5 meters should be fine, depending on the size of the TV.
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By Rasmus Larsen
#5670
Rescue wrote:Thank you for the detailed review..

Regarding the minimum distance for nondiscerning odd/even lines and 3D resolution battle...

....

All I would like to say is that in my opinion, the simplest resolution calculation per eye as a perception device by its own, here does not work and would not explain any phenomenons we see it. Therefore I am following this information quantity approach instead.
You're right and that is an interesting discussion. But we also have to remember another aspect when talking about passive 3D. The FPR (the passive film enabling 3D) covers a small percentage of the pixel (around 7-8 % I think). This is not visible from normal viewing distance but from close distance it is.

LG has sent me an email with a note telling that they have made some changes to the 3D processing algorithm used on their Cinema 3D models. I will tell more in a later article on the front page.
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By Rasmus Larsen
#5671
sinistro wrote:Chad B did mention on his review that on the 55lw5600 the threshold for him seeing those scan line was just a little more than 2M.

I guess that there is no difference between the 6 and the 5 series with this.
Yeah, I'm pretty sure it's the same with the 6 and 5 series.
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By Rasmus Larsen
#5672
blackbird wrote:Thank you for the review, just two doubts. You talk about the "local dimming" function (which is not a real local dimming because of the edge LEDs), but i did not understand if you are using it when you say that black level is 0.08 cd/m2.
If not, could you tell me if the black level can be lowered when this function is activated?
When "local dimming" is active do you see any "columns of light" or haloes around bright objects on a dark background?
Personally, I don't really see the benefit of "local dimming" on Edge LED models. Therefore it's always off in our reviews. 0.08 cd/m2 black was measured without local dimming, yes.

I did do some testing with the local dimming function on but in my opinion it has no real advantages. Black might be 0.01 cd/m2 deeper but the disadvantages are not worth it. I saw –as you mention - columns of light. But it actually looks more like the dynamic contrast systems that we saw on some older 2008 and 2009 models – we don’t like that…
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By Rasmus Larsen
#5673
powerboatnut wrote:Any input on the 120hz vs. 240hz question?

Anyone else heard that the passive (to join the present actives they offer) might be coming out from LG in the plasmas?
Sorry, I have only seen the 120 Hz Cinema 3D version a few times and have never had a chance to make a side-by-side comparison with the 240 Hz versions. But in my opinion passive 3D still looks good with the 120 Hz version based on the demonstrations.

I heard that LG's new Nano TVs will be delayed because of Cinema 3D. LG wants to change active 3D to Cinema 3D on all LCD/LED models. I'm not sure it's official at this point but I guess. I haven't heard anything about the plasma TVs, however.
Actually, I have already received the PZ950 plasma - it uses active 3D.
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By Rasmus Larsen
#5674
sinistro wrote:So far I know any image procesing will add inputlag so on this isue the 100/120Hz will have less or at least the same inputlag as the 200/240Hz.
Yes, image processing equals input lag. A general rule to reduce input lag is to deactive image processers. However, most plasma TVs tend to have lower input lag.
By sinistro
#5713
Does this new algorithm also decrease this line effect you talking about in your review?
The last point I want to discuss is actually a negative one. We usually recommend sitting close to a 3DTV for the best experience but with LG’s Cinema 3D you don’t want to sit too close. Why? Because you can see the pixels – or should we say lines. The polarized 3D glasses work by separating even lines from odd lines and projecting the different lines to each eye. Therefore you only see the even lines with the first eye and the odd lines with the other eye, and this effect is visible if you move to close to the TV panel