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Official 3D Projector Thread. - Page 12

post #331 of 346
It looks like a projector with a large (110+") screen is necessary for a true/real 3D effect.

I suggest that those of you who are thinking about getting an LCD, DLP or a plasma (50"-73") for 3D, while waiting for bright/affordable 3D projectors, read this review before buying.

While viewing the 65" Panny TX-P65VT20 3D plasma, TrustedReviews found that the 3D immersive effect wasn't quite there from about eight feet away.

Quote: "For the 3D effect to remain convincing the image needs to almost completely fill your vision and I think you'd have to sit six feet away from this TV to get the same fill of your vision as at a good cinema, which simply isn't practical for many people."

They also found that 3D wasn't that great with sports. Quote: "....3D added surprisingly little to sport and was a bit of a strain to watch."

And while you get two pairs of glasses with the 65" Panny, they suck. Quote: "Sadly the build quality of the glasses wasn't all that great and one fellow journalist managed to break the nose bridge of one pair. They were also nearly impossible to wear with glasses and generally weren't all that comfortable." Kids would break these in an hour, IMO.

Buyer beware.

http://www.trustedreviews.com/tvs/re...Impressions/p1
post #332 of 346
I'll sit 6 feet from a 65" no problem.
post #333 of 346
Or a 72 or 73 incher. Better glassses are and will be abailable for aftermarket purchase.

3D. I`ll babble about this again. There are various types of 3D effects. For example, an immersive effect, quite artificial to make one appear to be in the middle of a scene. The seeds floating around you in Avatar.

Other times, a 3D effect is used to add depth in a mid distance part of scene. Something your eyes wouldn`t see viewing the scene in place of the camera. Then there is what I would call real 3D, an object in the foreground appearing in depth as ones eyes would see it and distant objects appearing just as they do to your eyes, very 2D ish. When mid distance depth is added to a live scene, the foreground objects because of camera limitations appear in 2D, this happened frequently in Avatar. Your eyes woulsdn`t see it this way in real life. Everything in the foreground to your eyes will have depth.

Now sports. How do we view live sports. Both in real life, being there, and on TV? Real life, its all 3D of course. But what does this mean? If you sit far away from the action, its wide angle mostly 2D. If you sit behind the bench, you will see objects close to there with depth. Point is, 3D live sports cameras will have to be close to the action for 3D to make a difference. The overhead gyro cam etc. For telephoto shots, forget it. Will look like 2D. Just like your eyes would see it looking through a pair of binocs.
post #334 of 346
Hello everybody. Very interesting post. Thanks to all of you.

I am presently using a full HD FP (sony's pearl VPL-VW50) with a 1.0 gain screen and I am considering a 3D upgrade.
After carefull examination of all the different technologies, my best approach would be the 2 proj setup with polarized glasses.
(Buying a second-hand pearl when the current owner is wishing to upgrade to 3D with shutter glasses before the end of the year is likely to occur...)

As I understand, one of the issues seems to be brightness.

If I assume:
- 40% transmission due to the proj polarized filter
- 80% transmission for the glasses (should be 100% because the polar axis is the same)
(the above two give about 30% transmission, which seems to be admitted by the community)
- 200% gain because of the 2 proj setup
- lets add a 200% gain average due to the silver screen

In my case, I currently use the economic lamp powering, which can add another 50% brightness when fully powered.

All that gives: 0.4 x 0.8 x 2 x 2 x 1.5 = 1.92

Am I correct to assume that the issue will not be less brigthness, but too many lumens instead ???????????

Jack
post #335 of 346
Quote:


It looks like a projector with a large (110+") screen is necessary for a true/real 3D effect.

Let's remember that viewing angle and screen size are different topics... though if the seating distance was a fixed variable naturally the larger the screen the larger the viewing angle.

But if seating distance can vary, then a viewer could move closer to smaller screen and get the same effect.

Of course, the larger screen makes it *easier* to comfortably obtain a wider viewing angle since you don't have to move the seating as close to the screen.

I sit about 12 feet back from my 106" screen and it's magic. But if I had a 72" direct-view, I'd move my sofa closer to the display to maintain the same viewing angle for "immersion".
post #336 of 346
There are other 3D (or 3D-ish) effects that I'm still waiting for. The profound 3D revolution in movies took place about twenty years ago when graphics based on 3D drawing programs replaced graphics based on 2D paint programs. Avatar uses those 3D program tools just as Jurassic Park had a generation back. The original Star Wars films were all 2D in the sense that they used mattes and painted backgrounds. All the second round Star Wars films were 3D in the sense that most of the graphic elements were objects created in 3D software (eg. Jar-Jar Binks).

We can go further.

About a quarter of a century ago I heard Nicolas Negroponte speak at a computer conference in Sacramento. He had been the head of the Media Lab at MIT. He told us about the cool things they had been working on in the lab and made some predictions about things to come.

He described a TV broadcast of a baseball game. As he pictured it there would be cameras all over the stadium. The broadcast image was not the simple viewpoint of any one of these cameras. The image was computed in real time so as to show the action from any perspective. The camera/computers could show how some grounder would look from the perspective of someone in the good seats or from the bleachers. It could show it from the perspective of the batter or the shortstop. It could show it from the perspective of the ball.

When we go to the ballpark we perceive ourselves as existing in a 3D space. So we can imagine what an outfielder sees when he reacts to a ball hit out to him. If we can imagine it, we can create a technology that can image it.

For movies an object oriented (3D) approach yields other benefits. Negroponte described how in addition to the knob that we have now to adjust our TV's contrast and brightness, we will have a knob to adjust the level of violence and nudity.
post #337 of 346
For a while, the NFL was using some sort of multi-camera technology to analyze and show how a play looked from different points of view. It was the "Matrix" technology brought to a football game. I seldom see it anymore. Maybe it's just too expensive to implement.
post #338 of 346
Anybody want to answer Jack`s calcultion. It looks OK to me but what do I know?
post #339 of 346
Quote:
Originally Posted by mark haflich View Post

Anybody want to answer Jack`s calcultion. It looks OK to me but what do I know?

I am not sure if you can double the gain by adding a second projector. I am not sure what the equation is, but I think it is not linear.
post #340 of 346
Quote:
Originally Posted by DaViD Boulet View Post

spend some time reading this thread and you'll find answers to most if not all of your questions. The basic answer is that "it depends" as different 3D projection technologies/methods will have different pros and cons and different physical requirements.

My question did not relate to pros/cons, just simply what am I lacking to get 3D when I already have a front projector home theater. I spent the time reading this thread as suggested but the answer is lost in all the details. But I found the simple answer here...

What do I need to watch 3D?

http://hometheater.about.com/od/home...o_watch_3d.htm
post #341 of 346
Quote:
Originally Posted by mark haflich View Post

Anybody want to answer Jack`s calcultion. It looks OK to me but what do I know?

Thank you for taking care of me

Quote:
Originally Posted by bluesboyjr View Post

I am not sure if you can double the gain by adding a second projector. I am not sure what the equation is, but I think it is not linear.

I meant lumen count, not feeling. Lumen count is linear, feeling is not (logarithmic?).
I am going to have rougthly a 200% gain, that means more than my present 2D setup in any case... even if I stay with the economic mode....

Did anybody expect that?
post #342 of 346
Quote:
Originally Posted by forkdeath View Post

My question did not relate to pros/cons, just simply what am I lacking to get 3D when I already have a front projector home theater. I spent the time reading this thread as suggested but the answer is lost in all the details. But I found the simple answer here...

What do I need to watch 3D?

http://hometheater.about.com/od/home...o_watch_3d.htm

Simple answer? That's a laugh.

Just as the pros and cons "depend" on what 3D display technology you choose, so does "what you need to watch 3d". Some systems require a silver screen others don't. Some require expensive LCD shutter glasses. Others require less costly polarized glasses.

This thread and others on this board cover these issues in detail. If you really care about getting an accurate information, then read these threads. There is no "simple answer" to these questions at present in regards to front projection.
post #343 of 346
David. You are an idiot. Do you think he is asking a trick question? The simple answer is you need two eyes. That`s it. Open your two eyes. and duh you are seeing 3D. If the question is what do I need to create a 3D image in my home theater. there is a simple answer also. Duh, it depends.

You will need a pair of glasses designed to work with the particular display methodology you chose. You will need a regular screen or a screen which preserves polarization, depend if the display system you chose uses polarization, you will need one or two projectors depending on you know what, you will need special polarizing filters or color filter depending on you know what. A shutter glass system won`t require these, but an electronic device to split the left and right 3D images between two projectors will be required for a two projector shutter glass system, a one projector shutter glasses system will likely have the splitter built in. A 3D source will be required. I am simplifying of course because the complexity of the answer increases as the question is more narrowly defined.
post #344 of 346
Quote:
Originally Posted by jack-bauer View Post

I am going to have rougthly a 200% gain...

After a little more thinking about it, it appears I might have been wrong with my calculation.

If you consider only one eye, it only sees the projector it is supposed to, never the other one (which could be off as well, for what it matters...).

So a dual projector setup does not double the light, but does double the power consumption and the fan noise...!
post #345 of 346
Dual projectors do not increase the light, since you're half again when you get to the eyes. What is curious though (and mentioned in many studies) is that frame sequential systems (120Hz or 144Hz) do not cut the perceived brightness in half even though only one eye is seeing full brightness at a time.
post #346 of 346
Logically, the theoretical on/off ratio for a given eye is 50%.
Add to that a totally black period for both eye to avoid crosstalk and you end up with 30-40% light.

Assuming the shutter glasses have 80% transmission when on and you get roughly 25-30% for each eye.
So, because it is logarithmic, the "perceived" brightness could be 50%, not much more.

It is a good guess that both systems (dual projectors and frame sequential) will be equivalent in terms of brightness.
Still, dual setups will benefit from the silver screen added gain (but what prevents you to use a silver screen in the other case too?)

I am beginning to be disapointed as I was considering the dual setup. It is much less efficient as it doubles the power consumption for the same result. Somebody has to convince me that the dual setup obvious advantages (no flicker, cheap glasses...) make up for its drawbacks.
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