Passive 3D is it 1080?

[def lugs]

A quick question chaps,

Over the weekend we were out shopping so while my partner was emptying Boots the chemists. I headed into Curry's for a nose around. They had the new LG LM760 tv on display showing Despicable Me in 3D. I picked up a pair of the glasses from the stand in front of the TV and popped them on. The 3D effect was good with just the smallest hint of ghosting. However I was surprised to see that the resolution dropped. I am presuming that alternate lines were displaying the picture for each eye.

My question is do all passive technologies lower the resolution in the same way?

cheers

 

[bigboss]

http://stijndewitt.wordpress.com/2012/02/04/active-vs-passive-3d-myth/

 

[def lugs]

Thanks BB useful article. I had initially thought that the passive TV's displayed alternating L R images rotating the polarisation between for each image. I had not given any thought to how the polarising technology worked. When I googled last night I think that LG's claim that the technology is full HD is misleading, yes the image is still made up from 1080 lines but with only half the resolution shown twice.

 

[Andy Clough]

You might also find this article useful def lugs.

 

[def lugs]

Thanks Andy,

To my eyes it still looks lower resolution VDE certificate or not - I am happy to accept maybe this method just does not work with my eyes and brain. When I was stood a couple metres in front of the set without the glasses on the sky in the movie was continuous shades of clouds and blue sky. Putting on the glasses I could easily determine the horizontal lines of pixels which were not apparent without the glasses, this manifested itself as thin black lines between each row of pixels.

I understand the image is made from 540 lines for left and 540 lines for right = 1080. Surely these must be the same 540 lines repeated for each eye which is still only half the resolution of a true 1080 picture.

All that said in normal viewing the picture was very nice and smart tv side of the box was also pretty slick.

 

[strapped for cash]

Well, LG and co. can claim that passive 3D offers a full 1080 lines of picture information by sending 540 lines to each eye simultaneously, but active shutter 3D still delivers a higher resolution image by sending 1080 lines of picture information to each eye alternately (at double the frame rate of passive 3D).

Passive 3D offers a cost advantage and arguably suffers less from crosstalk (because the glasses don't need to be synchronised with the display), but the trade off IS lower resolution.

 

[Ryan92]

I think it depends on how you define 1080 really. For me, I'd say passive is worse, as each image each eye sees a lower resolution image. Active having a full image for each eye, which would average out as two full 1080 images, one for each eye, only being displayed for half as long. The overall effect being a better "resolution" in a sense. But, introduces flicker and the fact each eye is essentially seeing a black screen half the time means you will lose brightness. Good TVs do there best to minimise this and in my opinion are pretty good at it, making active 3D my preference. The only reason I'd go for a passive would be if I had young kids/big family. But I'm 19 and selfish . . 🙂