Popular IT channel Linus Tech Tip on 3D

[Jlardonio]

Originally Posted by lukas741

I understand...If you are happy and satisfied...nothing else really matters. Thank you for that back and forth conversation event...I guess I needed to vent about something even though I was having concerns about other matters in my life... a very sick mom...take good care.

No problem, this is a forum for argument and counter-argument.

Very sorry for the health of your mom, i wish her the best and a good recovery.

All the best for you too.

[Just_Discovered_3D]

Originally Posted by trialobite

Ironically, I’m writing this post on my phone with active 3D glasses on while playing Doctor Strange on the TV but yes, in general 3D content/glasses definitely helps cut down on distraction/phone use. I’m rewatching Strange with the commentary track after doing a separate watch a couple weeks ago.

And I think maybe you’re joking about 2 projectors and a rig not being that pricey? Obviously everyone will have a different income level so “expensive” is relative, but I would guess that for most people, the projector is the single most expensive piece of equipment in their home theater. Doubling that price, plus the polarization rig, just to use passive vs active lenses is a bit extreme for a lot of people. If you’ve got the disposable income to do it, by all means, more power to you and I am jealous!

On projectors, I have noticed that they do not really hold their value on the used market, so buying 2 decent projectors for a few hundred bucks total is doable.

For example, I needed a Full HD 3D projector that I could travel with, and after a few weeks casually looking on eBay I landed one for under $200. In the $300 to $400 range you could likely buy it now, since factory refurbs seem to be from $350 to $500, which puts a relatively solid price ceiling onto used projectors

With some patience, 2 Full HD 3D projectors and a polarized screen could be done for around $1,000, more if you buy a rig to align them. That's a somewhat serious sum, though it is about twice what Sony sold that PS 3D TV for, which Linus considered to be terrible, and it is 1/16th of what he said his cream of the crop 3D TV retailed for.

Originally Posted by Jlardonio

Yes, what everyone want is to have some glasses that can brake and stop working or lose power and then hurt their 3D experience... not mentioning of watching the movies with natural light and have every other object in the view field flickering. :/

Passive not only is cheap it also doesn't have the downsides of active glasses, you may be proud of your TV and glasses set, but most people aren't prone to have complicated gizmos and to have hassle with them.

DLP-Link active glasses are incredibly simple to use. Just turn them on and they work, a rare example of a plug-n-play technology working. They sync themselves, the most work you'll have to do is to click a button on the glasses to invert the sync, and that's not always required.

Natural light, and even artificial light, aren't dealbreakers with 3D on a projector. They wash the image out, of course, but the tech can still work with some of them present. Although IMHO a movie should be watched in an environment with minimum light.

My active 3D glasses have gone through many episodes and films on a single charge. I did have a pair run out of power the other week during a film, but swapping in a spare pair only took a few seconds.

At $12 to $20+ a piece, active glasses are significantly more expensive than passive glasses. For a movie theater that has thousands of patrons that matters, but for a home audience I'm not sure it does. Anyone who can afford passive 3D projection can afford dozens of active 3D glasses. It seems to me that 3DTV owners don't need to buy that many glasses as only a few people can watch a 3DTV at the same time.

Originally Posted by Jlardonio

And it does show brightness enough that i have it just on 10% of power to watch any 3D movie i want to not have reflections on the glasses.

As i could watch on that video, Playstation 3D Display had also 720p on active 3D. Maybe that's why people stoped to like 3D. Playstation as a great brand selling bad 3D displays hurts whoever who bought it.

With active 3D, in a darkened/dark room, I have not had an issue with the glasses reflecting the 3D movies.

[trialobite]

Originally Posted by Just_Discovered_3D

On projectors, I have noticed that they do not really hold their value on the used market, so buying 2 decent projectors for a few hundred bucks total is doable.

For example, I needed a Full HD 3D projector that I could travel with, and after a few weeks casually looking on eBay I landed one for under $200. In the $300 to $400 range you could likely buy it now, since factory refurbs seem to be from $350 to $500, which puts a relatively solid price ceiling onto used projectors

With some patience, 2 Full HD 3D projectors and a polarized screen could be done for around $1,000, more if you buy a rig to align them. That's a somewhat serious sum, though it is about twice what Sony sold that PS 3D TV for, which Linus considered to be terrible, and it is 1/16th of what he said his cream of the crop 3D TV retailed for.

I think we’re pretty much in a agreement here, but if any prospective projector buyers read this thread, I would like to say that you will likely be sacrificing a LOT of quality to get those 2 projectors for a polarized rig, versus spending the same money on a single projector with active glasses. I’ve been running PJ’s for around 15 years, and recommend spending the top end of your budget on one high-quality unit. If your budget is $1000 (or any other arbitrary number) you’ll get much better performance, brightness, contrast, and black levels by spending that money on a $950 projector and $50 active glasses, rather than 2 projectors and the polarizer. There is such a huge jump from Home Theater projectors in the $300-$500 range, to the $1000 range, to the $3000-$5000 range. I fully agree with the rest of your post that for individual buyers, active glasses are convenient and easy to use. Unless you have an unlimited budget or plan on regularly doing showings for more than 4 people at a time, the best use of your budget is going to be on a higher quality single projector.

[Jlardonio]

Originally Posted by Just_Discovered_3D

DLP-Link active glasses are incredibly simple to use. Just turn them on and they work, a rare example of a plug-n-play technology working. They sync themselves, the most work you'll have to do is to click a button on the glasses to invert the sync, and that's not always required.

Natural light, and even artificial light, aren't dealbreakers with 3D on a projector. They wash the image out, of course, but the tech can still work with some of them present. Although IMHO a movie should be watched in an environment with minimum light.

My active 3D glasses have gone through many episodes and films on a single charge. I did have a pair run out of power the other week during a film, but swapping in a spare pair only took a few seconds.

At $12 to $20+ a piece, active glasses are significantly more expensive than passive glasses. For a movie theater that has thousands of patrons that matters, but for a home audience I'm not sure it does. Anyone who can afford passive 3D projection can afford dozens of active 3D glasses. It seems to me that 3DTV owners don't need to buy that many glasses as only a few people can watch a 3DTV at the same time.

If you have a lot of people, family(kids and grown ups) and/or friends, in a party or something like that that you want to show a great 3D movie... you think that with an projector/TV you'd be able to do it with those active glasses? Have to explain them to sync and some having inverted signal and to correct? Having all that hassle that the 3D experience would be good? Let's say, some 12 to 20 people, would you be able to project the movie to them all with glasses and not being most of the first minutes giving instructions so the glasses would be working normally? Would that be a good 3D experience? Some out of the picture and others having to be instructed about the use of the tech to watch a movie with the possibility of 1 pair or two not working?

I have 16 pair of glasses and i just paid for 1 pair, the rest was LG offers with the TV and a pair that the theater offered me. Even if i needed more it would be inexpensive and easy to get. And they would have just to put them on and watch, that really simple move.

Originally Posted by Just_Discovered_3D

With active 3D, in a darkened/dark room, I have not had an issue with the glasses reflecting the 3D movies.

And with light in the room? And your skin reflecting the light of the room and movie because of the intensity? Maybe you're mixing subjects... when i say that i lower the tv power to 10% i'm saying that the tv is so bright that i need it to be on that level to have an good experience like if i was in a cinema room even without the same conditions(black room and no lights) and you with your projector must have your settings that match the needs to work with your glasses that compared to passive glasses don't let so much light to pass and possible match with my TV intensity or close.

Like i said. People need standardization on 3D and passive 3D is a game winner. Maybe one day we'll have the autostereoscopic TV/projection to replace the glasses but until then the passive 3D is the most successful way to watch 3D for most of the consumers if we want the format to survive.

[revgen]

Originally Posted by Just_Discovered_3D

When Linus says that the LCD is not fast enough to stop ghosting, is he referring to the LCD in the glasses, or to the LCD of the PlayStation 3D TV?

Frankly, 120-144 Hz glasses are too slow for active 3D (this goes for theatrical RealD as well). Linus is right that the 3D makers price gouged back in the day, as today's DLP glasses are more convenient and $15 a piece. DLP projection removes many of the downsides of active 3D that they mentioned, and turn them into assets...perhaps active 3D should have been for projectors or dark room viewing only?

This article explains why DLP projectors don't suffer from crosstalk.

Most consumer level DLP projectors use a single DMD imaging chip and a motor driven rotating “Color Wheel”. With this arrangement the color wheel sequentially displays as a minimum, the primary colors (red, blue and green) while the DMD chip displays only the elements of the image that corresponds to the wheel color currently in the light path. Thus the image on the screen is rapidly showing a sequence of single color images and the human eye/brain puts these together to form the desired full color image.

....

High-end DLP projectors (typically costing over $15K) frequently use 3 DMD chips with one for each of the 3 primary colors (the 3 chip arrangement is similar to the configuration used with all LCoS and LCD projectors). Frequently these 3 chip DLP projectors project a brighter (i.e., higher lumens) image and do not suffer from the rainbow effect of the single chip/colorwheel models.

On the positive side such single DMD chip DLP projectors do not suffer from misconvergence of the primary colors (i.e., misconvergence is a slight misalignment of the red, blue and green primary colors that make up the projected image) as is frequently the case with projectors that use individual imaging chips for each of the 3 primary colors.

...

The DLP Advantage for 3D

One of the most frequent complaints when viewing 3D, either in a commercial movie theater or in a home theater environment, is 3D Crosstalk (or 3D Ghosting). This occurs when one eye sees some elements from the image intended for the other eye. Some experiments indicate that if the brightest elements of the alternative image (the unwanted image intended for the other eye) are more than 0.1% as bright as the desired image then some viewers will be able to detect crosstalk on certain scenes. However, most viewers will find 3D displays that are capable of suppressing the alternative images to levels on the order of 0.5% to be reasonably good with 3D crosstalk only occasionally being noticed. With active 3D projection systems crosstalk will generally originate from any of the following 3 sources (assuming the source 3D device provides a crosstalk-free signal into the projector).

1. The display chip within the projector is not able to fully replace all elements of the previous image with the new (i.e., next) image fast enough, thus allowing some traces of the previous image to remain on the display when only the new image should be displayed.

2. The synchronization of the timing between the projector and the 3D active shutter glasses must be very precise otherwise a lens of the glasses may become transparent too early or opaque too late and as a result briefly allow the previous or the next image (i.e., intended for the other eye) to be seen. This timing is complicated as a result of the lenses being used in the active shutter glasses are made from liquid crystals that themselves take some time to fully transition between opaque and transparent states. This transition time typically will be between 0.5 millisecond and 2 millisecond depending on the specific 3D active shutter glasses being used.

3. If the lenses of the 3D active shutter glasses do not become adequately opaque to fully block all visible light that is intended to only be seen by the other eye, then there will be visible 3D crosstalk.

While projectors using LCoS or LCD technology may suffer from 3D crosstalk due to any of the three above sources, DLP projectors inherently do not suffer from item 1 above as the DMDs used with DLP projectors are able to fully transition from one image to the next without the possibility of the any remaining traces from the previous image. Thus if you do see 3D crosstalk with a DLP projector the cause originates from item 2 and/or 3 above (or is present in the source 3D signal).

https://www.projectorreviews.com/hom...on-technology/

The best way to avoid issue #2 on DLP projectors is to use RF glasses instead of DLP-Link.

[Just_Discovered_3D]

Originally Posted by trialobite

I think we’re pretty much in a agreement here, but if any prospective projector buyers read this thread, I would like to say that you will likely be sacrificing a LOT of quality to get those 2 projectors for a polarized rig, versus spending the same money on a single projector with active glasses. I’ve been running PJ’s for around 15 years, and recommend spending the top end of your budget on one high-quality unit. If your budget is $1000 (or any other arbitrary number) you’ll get much better performance, brightness, contrast, and black levels by spending that money on a $950 projector and $50 active glasses, rather than 2 projectors and the polarizer. There is such a huge jump from Home Theater projectors in the $300-$500 range, to the $1000 range, to the $3000-$5000 range. I fully agree with the rest of your post that for individual buyers, active glasses are convenient and easy to use. Unless you have an unlimited budget or plan on regularly doing showings for more than 4 people at a time, the best use of your budget is going to be on a higher quality single projector.

Personally I'm in a holding pattern on the pricier projectors as the neat new laser projectors are a complete no-go for gaming (2D or 3D), and no projector has yet broken the 60 Hz barrier for 4K. Supposedly they could currently display 4K 3D, with a software patch, which would be fine for me, but since it has not yet happened I'm holding off for that next evolution in projection.

Originally Posted by Jlardonio

If you have a lot of people, family(kids and grown ups) and/or friends, in a party or something like that that you want to show a great 3D movie... you think that with an projector/TV you'd be able to do it with those active glasses? Have to explain them to sync and some having inverted signal and to correct? Having all that hassle that the 3D experience would be good? Let's say, some 12 to 20 people, would you be able to project the movie to them all with glasses and not being most of the first minutes giving instructions so the glasses would be working normally? Would that be a good 3D experience? Some out of the picture and others having to be instructed about the use of the tech to watch a movie with the possibility of 1 pair or two not working?

I have 16 pair of glasses and i just paid for 1 pair, the rest was LG offers with the TV and a pair that the theater offered me. Even if i needed more it would be inexpensive and easy to get. And they would have just to put them on and watch, that really simple move.



And with light in the room? And your skin reflecting the light of the room and movie because of the intensity? Maybe you're mixing subjects... when i say that i lower the tv power to 10% i'm saying that the tv is so bright that i need it to be on that level to have an good experience like if i was in a cinema room even without the same conditions(black room and no lights) and you with your projector must have your settings that match the needs to work with your glasses that compared to passive glasses don't let so much light to pass and possible match with my TV intensity or close.

Like i said. People need standardization on 3D and passive 3D is a game winner. Maybe one day we'll have the autostereoscopic TV/projection to replace the glasses but until then the passive 3D is the most successful way to watch 3D for most of the consumers if we want the format to survive.

Explaining how to fix inversion isn't an issue that I have found because it does not happen often, and if it does happen it is inverted for everyone, so I'll see it and can fix it for everyone with the invert sync option on the projector.

For the glasses that have the Invert button on them, my experience has been that folks like to have fun clicking it. I know I have fun with it myself sometimes, as it can, particularly with at-home 3D conversions, have interesting effects.

Regarding light reflection, in DLP link mode the projector sets itself to a very bright output, which would cause reflection issues except the active glasses greatly eliminate it. They also enhance the contrast of the image. There's also a strong immunity to ghosting

On the glasses themselves, 16 pairs of active glasses would be an expense for sure. While they can be had cheaper elsewhere, glancing at US Amazon shows that it would cost between $180 and $292. Despite their increased weight, I am told by my prescription-glasses-wearing pals that wearing active glasses over their normal glasses is more comfortable than wearing the passive RealD glasses over their normal glasses. The RealD glasses have small lenses, thick frames, and are not ergonomic.

In the past you've mentioned clip-on passive glasses, which would be more comfortable than active, but wearing two pairs of glasses does not seem to be an issue.

Originally Posted by revgen

This article explains why DLP projectors don't suffer from crosstalk.



https://www.projectorreviews.com/hom...on-technology/

The best way to avoid issue #2 on DLP projectors is to use RF glasses instead of DLP-Link.

Thanks. RF glasses would be interesting for sure, since they do not deactivate themselves when looking away from the screen.

When my glasses have lost sync, due to scenes being too dark on a screen that might not be reflective enough, I still have not noticed ghosting, just a mild color shifting and the image turning flat.