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While the lightness of the passive 3D glasses is all good and fine, where it truly matters, the picture quality department, passive is abysmal. This must be the resolution thing people talk about. 3D Blu-rays looked only 720p and there were obnoxious black horizontal lines running across the screen, every other line. I can describe it only as like looking outside a window through a set of blinds. So not only does passive 3D on a TV halve the resolution, you can see the half of the resolution it cuts out in the form of black bars! WTF? I think this passive 3D technology LG uses infects 2D viewing too: Everything I viewed on the panel looked interlaced.

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First of all there is no perfect system. Each has advantages and tradeoffs. The black lines in the Passive system are real and there are two recognized solutions to these lines that reduce your vertical resolution in 3D.
1. Sit farther away so that your vision can't see them.
2. Buy a 2160p (4K) passive that will display the 3D content at an effective vertical resolution of 1080p while increasing the sharpness in the horizontal to 3840 pixels.

Currently we still wait for good pricing on the 4K passive LED TVs but it is coming and soon. Soon enough that in my opinion it is worth the wait.

On the Home Theater Cruise, Joe Kane demonstrated empiracle tests that prove the passive systems reduce visual vertical resolution in half for 3D but maintain the horizontal. He prefers active for this reason. 2D content, however is not affected in this way. The reasons are complex, too complex to discuss here as it took Joe more than 6 hours of discussion to review all the data he has collected but in my opinion the debate is over and Passive does cut resolution in the vertical for 3D.

Anyway, I also disagree with Joe and you that Passive monitors are "abysmal" As for enjoyment and entertainment, there is more to the story than simply vertical resolution. If I want to watch 3D content for long hours, the passive glasses fatigue me no more than sunglasses. However, my active glasses do cause eye fatigue after about 90 minutes and require a 30 minute break after 2 hours. Both my wife and I have the same complaint about active so the benefit of higher vertical resolution is outweighed by the fatigue factor of active glasses.

Having seen the 4k passive LG monitors in LED, the lines you speak of are gone, even when viewing up close. Because of the increased horizontal resolution from 1920 to 3840 the image detail and sharpness is improved. I do agree that the 4K passive 3D displays will still show less vertical resolution in 3D than the same monitor with 2D content but it appears that in a 65" diagonal size those annoying black horizontal lines we had on the 2K passive panels are gone at normal viewing distance. Also as a side benefit, the aliasing and diagonal jaggies of passive are also gone. Joe Kane agrees that the answer to the problem of FPR resolution reduction in 3D is all but resolved with 4K panels.

Of course, as we up the scale on the source content to 4K content, then the issue begins all over again, but these issues also have a screen size threshhold that is also larger. Joe believes that in his studies these similar problems with 4k content will again surface when screen sizes exceed 110". Again, Joe does not rely on marketing blabber but rather empiracle data for his statements.

Conclusion- with screen sizes of 84" or less, 4K LED monitors with 2K content ( what we will have in the near future ) is the best of all worlds.

Don Landis said:

First of all there is no perfect system. Each has advantages and tradeoffs. The black lines in the Passive system are real and there are two recognized solutions to these lines that reduce your vertical resolution in 3D.
1. Sit farther away so that your vision can't see them.
2. Buy a 2160p (4K) passive that will display the 3D content at an effective vertical resolution of 1080p while increasing the sharpness in the horizontal to 3840 pixels.

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1) Is not an option. The TV is in a smaller room and it's a 46" model. My face is 4 feet away from the screen. Why would I want to sit farther back when it comes to a TV this small? You are meant to sit closer, the smaller your television is. I want a field of view that is filled with picture, not a small rectangle surrounded by white wall.
2) This defeats the entire purpose of a 4K TV. Why would I want to turn a 4K TV into a 1080p TV every time I watch 3D any more than I want to turn my 1080p TV into a 720p TV every time I watch 3D? I'll have to see whether 4K is a resolution high enough that a decrease in resolution will be noticeable, but I suspect we are going to need 8K TVs, because once we're all used to 4K just like we are with 1080p, a resolution cut is going to be noticeable. 4K still is an insufficient resolution when it comes to maximizing the human eye's capability. As it stands now I can count the pixels on my 46" 1080p TV so full 4K is definitely needed.

I'm not entirely sure how passive works in theaters but that should be a model for the way passive works in the home. This resolution halving, black bar thing seems like the tech was half-assed when porting it to the home viewing environment.

Xizer said:

1) Is not an option. The TV is in a smaller room and it's a 46" model. My face is 4 feet away from the screen. Why would I want to sit farther back when it comes to a TV this small? You are meant to sit closer, the smaller your television is. I want a field of view that is filled with picture, not a small rectangle surrounded by white wall.

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If your room is small enough that you are sitting 4ft from a 46" screen, then the TV is entirely too big for the room. A 46" TV is designed for a viewing distance of 6-10ft. If you're sitting 4ft away of course you're going to notice artifacts. You should've bought a 32".

2) This defeats the entire purpose of a 4K TV. Why would I want to turn a 4K TV into a 1080p TV every time I watch 3D any more than I want to turn my 1080p TV into a 720p TV every time I watch 3D? I'll have to see whether 4K is a resolution high enough that a decrease in resolution will be noticeable, but I suspect we are going to need 8K TVs, because once we're all used to 4K just like we are with 1080p, a resolution cut is going to be noticeable. 4K still is an insufficient resolution when it comes to maximizing the human eye's capability. As it stands now I can count the pixels on my 46" 1080p TV so full 4K is definitely needed.

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Under normal circumstances with a 1080p source you are not losing resolution with passive 3D. It does not interlace the left and right. 3D sets run at 120 or 240Hz - double what a standard TV scans at.. Meaning a 1080p 3D set with a 1080p source draws a 1080 line left polarized frame for the left eye, followed by a 1080 line right polarized frame for the right eye twice for EACH frame of the source (assuming a 120Hz set). You do not lose resolution.

I'm not entirely sure how passive works in theaters but that should be a model for the way passive works in the home. This resolution halving, black bar thing seems like the tech was half-assed when porting it to the home viewing environment.

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It works essentially the same as it does in a passive 3DTV. So if you're seeing "black bars", then you're doing something wrong.

Broadcast is another story. Most will be interlaced. DirecTV's 1080p PPV and I believe n3D will give you full 1080p3D.

JerseyMatt said:

Under normal circumstances with a 1080p source you are not losing resolution with passive 3D. It does not interlace the left and right. 3D sets run at 120 or 240Hz - double what a standard TV scans at.. Meaning a 1080p 3D set with a 1080p source draws a 1080 line left polarized frame for the left eye, followed by a 1080 line right polarized frame for the right eye twice for EACH frame of the source (assuming a 120Hz set). You do not lose resolution.

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You are describing the way an active 3D TV works with glasses that have shutters. I disagree with that explanation for passive sets and passive (polarized) glasses. If what you say above were true, then the loss of resolution seen by Xizer, and described above by Don, wouldn't be happening.

What's really happening for a passive set, according to yours truly, is the left and right circular polarizers are in front of only half the pixels. So if you close one eye and look closely, you'll see the black bars Xizer is complaining about. Those black lines are the parts of the picture that should be seen by your closed eye. I completely agree with your viewing distance observation. 4' for a 46" screen is too close, since (in 3D mode) you're only seeing half the vertical resolution (540 lines). This loss of resolution is why Don is recommending 4K TVs for typical screen sizes and viewing distances when the 3D TV in question is passive. You won't see this loss of resolution on an active (shutter) system, because the same pixels are time-multiplexed at a high refresh rate.

JerseyMatt said:

It works essentially the same as it does in a passive 3DTV.

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Passive 3D theatrical presentations work the same as passive 3DTVs with one BIG difference. There are two projector lenses (one for each left/right image), and the polarizers are at the exit from those lenses. Actually I don't now whether there are two lenses or not, but anyhow the polarizers are in the projector, not on the screen. All the screen has to do is not scramble that polarization when it's reflected back at the audience. There is no loss of resolution because both left and right images are present on the same "pixel" on the screen all the time.

Nvm.

The Krell

Thank You! You have an excellent understanding of the technology. My only advantage over what you explained is that I have seen Joe Kane's data where he proves these concepts scientifically. Sometimes the rhetoric gets a bit confusing e.g. the term "Black Bars" is not really a good one since there really aren't any "Bars" like we used to think of them in aspect ratio and filling up the screen real estate. In the case of 3D passive, there are horizontal black lines that can be seen, 540 of them that lose 50% of the vertical resolution. I prefer to call them "lines" not "bars" The 2160 screens have them too but they are now half the width and get blended easier into the image at the same screen size and distance. I think a 45" 4K FPR passive would probably work for a person sitting 4 ft in front of a 3D screen in his tiny room. But, it is unlikely that the manufacturers will be making a 46" 4K anytime soon. Current plans are for a 55" and a 65" to go with the 84" currently being sold. Hisense may offer a 110" this year too. Haven't heard what Vizio plans but they will have a line too.

I use a 32" here in my edit room and sit 5 ft from the screen and have no problem seeing the horizontal lines when I go to 3D but I'm not bothered by it because I only edit with the TV to verify depth and occlusion issues in 3D. If and when the 4k 32" comes out, I will upgrade. For viewing, I use a FP projector system in a 12 x 20 ft room with a 110" diag screen. I use a Sony VPL VW90ES projector.

The idea that we should have passive in the home theater like the movie theaters is a nice idea and a few people have spent the money to do this with twin projectors and silver screens. I have never seen these twin systems for passive. But these systems also require a second non silver screen for 2D viewing. LG showed a system last year for 3D passive but it still required a silver curved screen to avoid the viewing angle restrictions on the flat passive polar systems. Still the color and contrast ratio was poor and image washed out. That plus Projector was $21000. It could only be used for 3D. They didn't show it this year. All the companies doing research into FP passive systems were gone from this years CES. Home theater is not ready for this yet. Can be done, very expensive and complex. Not really worth it. I need a roll up screen so for now, I'm stuck with active front projector for a 110" screen size. I'm enjoying my FP just fine. A few complaints but overall we love it.

Too bad there was no work on passive projectors this year. I would really consider a silver screen with a passive 3D projector. I really like circular polarization 3D over active shutters.

I love my little Vizio, bad thing is that it's in the camper and it has been pretty cold lately to just go out there and watch(plus fire up the heater etc)...