3D TV - I don't get what the difference is....

[PaulWood]

...Ok, so one of the major stumbling blocks is that most TVs don't accept the 120Hz incoming signal, and don't have the necessary processing power.

But why does it need to be sent out at that frequency, and why does it need more power?

In the cinema, we mostly use passive polarized glasses, and the 3D image is created by "dual images" on the print (ie, there is no need for 2 projectors).

The new 3D TVs use active liquid crystal shutter glasses, which are sync'd with the TV (using Bluetooth, wireless, or other connection).

So.... as most of the work in creating 3D is in the filming and rendering of the content, why can't it be viewed on a normal TV (as it is projected through a "normal projector" in the cinema).

Cheers!

Paul

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[A.C.Edwards]

I'm by NO means an expert here, but the cinema projection for 3d is based on a different type of canvas i've read. Something to do with silver.. Like I said, no expert, but maybe its do with the actual projection / viewing matieral, rather than the glasses and whatnot

 

[PaulWood]

I saw Avatar last week and it was a perfectly normal screen.... Dolby has some kind of technology that allows that. Not sure what it is.

 

[Brian Ralston]

Think of it like the refresh rate on a computer monitor. It's how many times the screen is being redrawn per second. A normal monitor (in order to reproduce a smooth normal picture) is at least at a refresh rate of 60Hz. 3D would need twice that because the way it is being done is there would be two pictures needed to be displayed per eye. Since they are slightly different images. So for each eye to get the benefit of a 60Hz screen...the overall refresh rate of the screen would need to be at least 120Hz. The screen "redraw" would just be twice as fast.

 

[Brian Ralston]

I saw Avatar last week and it was a perfectly normal screen.... Dolby has some kind of technology that allows that. Not sure what it is.

Dolby 3D creates the 3D images by using slightly different wavelengths of Red, Green, Blue for each eye. When I say slightly, I mean only a couple nanometers apart. Then the glasses you wear filter for those different wavelengths of light in each eye.

And as a little fun fact...Dolby did not create the "Dolby 3D" technology. A little German company did...they just licensed it, branded it and had the corporate power to put it out there on a mass scale.

 

[Nick Batzdorf]

https://www.nytimes.com/2010/02/04/techn ... technology

 

[PaulWood]

Thanks guys!

So Brian - are 3d films filmed at a higher speed than 24fps? Surely the refresh would be fine then because 24x2 is 48 - well within the limit of a 60Hz refresh rate...

Thanks Nick. To be honest, for the amount of content that will be available, it seems a bit of a rip off at the moment. I've never been an early adopter anyway... I think I'll wait for 3D TV SP2 to be released

 

[synthetic]

At the last few NAB shows, companies have been showing 3D TV with no glasses required. Freaky stuff, it jumps right out at you.

Apparently it's easier to do on smaller screens, so I'm looking forward to my 3D iPhone. Mostly so I can show it off to people with old, 2D iPhones.

There are about 20 3D systems right now. Real 3D, etc. I was at Fox yesterday talking to someone who worked on the color correction for Avatar for all of the different systems. Different aspect ratios, screen colors, etc. It's a nightmare right now.

 

[Brian Ralston]

Thanks guys!

So Brian - are 3d films filmed at a higher speed than 24fps? Surely the refresh would be fine then because 24x2 is 48 - well within the limit of a 60Hz refresh rate...

No...they are just doubling frames...sometimes quadrupeling frams and interpolating "mid" frames with the onboard computer. (as in the case of the 240Hz displays.

The TVs are using glasses with LCDs that shutter for each eye in synch with the Hz frequency of the screen. So...each eye only sees half of what is there. So you need the 120Hz to get a full 60Hz of picture image for each eye.

The intent of the increase in Hz is to give more fluid motion to the fasò‹ÿÂû÷‹ÿÂûø‹ÿÂûù‹ÿÂûú‹ÿÂûûŒÂüŒÂüŒÂüŒÂü ŒÂü
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