For passive polarized with 2 3d projectors do u need lenses?

[smoothy]

Hey Guys,

I got 2 questions

First I would like to say that AMD have presented now their new stereo 3d solution. It's called AMD HD3D, their GPU's are equipped with both HDMI 1.4a and displayport 1.2.

I was thinking if you got a 720p or 1080p 3d projector that has displayport 1.2 then get 2 of these projectors could you do passive, by daisy chaining them. Then would it be possible as they are already 3d ready projectors to not have to use lens filters for the passive polarized setup?

[BlackShark]

I believe you'd have to rewrite the laws of physics for that to change polarisation by the power of the graphics card.

Either your projectors are designed to be used in a polarised system, then the polarisers are already included in the projectors, or the projectors are 3D ready designed for shutter glasses, then you'd have to add filters and battle against the drivers to tell the driver that you do not want to use the shutter mode.

[smoothy]

I believe you'd have to rewrite the laws of physics for that to change polarisation by the power of the graphics card.

Either your projectors are designed to be used in a polarised system, then the polarisers are already included in the projectors, or the projectors are 3D ready designed for shutter glasses, then you'd have to add filters and battle against the drivers to tell the driver that you do not want to use the shutter mode.

Many thanks for your reply

I never said the gpu would change polarization. I know that could never be possible. The AMD drivers work with the 3d over HDMI and displayport 1.2 so both active/passive 3dtv's and projectors can pick up the format. I was just asking whether 2 3d capable active 3d ready projectors could be used in a passive setup without needing lens filters. From your answer I see this is not possible. Which is a shame. But daisy chaining 2 displayport 1.2 projectors for a passive rig with filters on each lens should work without needing any additional 3d conversion box like the optoma 3D-XL converter. Would you say that is correct?

As I am talking about doing passive, you don't actually need 3d ready projectors. They don't need to be 120hz. So when will we see 720p and 1080p non 3d projectors with displayport 1.2 that allow daisy chaining for creating a passive 3d setup?

[android78]

Please excuse my uneducated response, but I don't quite understand the 'daisy chaining' you're referring.
I thought that you should be using a dual output graphics card then you can hook one output to each projector.
You would still need to have polarizing lenses on the projector and polarization preserving screen if you want this to be passive.
The other consideration is that DLP is best for passive solution since the display element doesn't polarize the light as happens with LCD.

I wonder if anyone has tried just using an extra pair of RealD glasses with a dual projector setup. could be a cheap way to go, but may get more ghosting then professional circular polarizing lenses.

[smoothy]

Please excuse my uneducated response, but I don't quite understand the 'daisy chaining' you're referring.
I thought that you should be using a dual output graphics card then you can hook one output to each projector.
You would still need to have polarizing lenses on the projector and polarization preserving screen if you want this to be passive.
The other consideration is that DLP is best for passive solution since the display element doesn't polarize the light as happens with LCD.

I wonder if anyone has tried just using an extra pair of RealD glasses with a dual projector setup. could be a cheap way to go, but may get more ghosting then professional circular polarizing lenses.

Your absolutely right, it seems that I have got a little confused. Like you said I now see that it's far easier to just connect each output from a dual output gpu to each projector. But does that even work with the AMD Catalyst 10.10 drivers which introduce the AMD HD3D drivers?

So as I got confused a long the way, let me change the original question a bit. When displayport 1.2 projectors come out, whether they are 3d or non 3d ready and LCD or DLP could you just daisy chain them using the displayport 1.2 to creative a passive rig and will they work with the PS3 for passive stereo 3d? or would the PS3 need a firmware update? and please tell me, can the ps3 convert the 3d over hdmi signal to 3d over displayport 1.2?

Many thanks in advance

[BlackShark]

Daisy chaining could already be used today for dual projectors if such projectors were available. Display port daisy chaining is completely independent of the display types you use.
However this 3D dual-projector system is not officially supported by the HD3D drivers because in it's current implementation, ATi HD3D does not understand what a dual projector system is, you basically have to do everything by hand though specific apps and 3D drivers (just like with the current situation with dual projectors).
I've written to the ATi technical support to suggest them to support dual head outputs through the HD3D program but I haven't received an answer yet.

At the moment the only way you could daisy chain using ATi HD3D would be if the projector is designed specifically to do it : basically the first projector would claim to be a dingle display through hdmi1.4 or DP1.2 3D compliant to the graphics card, receive both left and right eye views, keep one for itself and hand over the other eye to the second projector though whatever connection it's designed to use.
It could use a secondary DP conntection, a HDMI conenction, a DVI connection or a completely different proprietary cable since this method is completely non standard.
Because this is a feature that has to be added on purpose, no single projector on the market (be it 3D ready or not) will ever support such a thing unless the projector is designed to be used specifically for this usage (basically a projector you can't buy alone, and which is produced and sold only by pairs as a complete 3D system).
There is already one example that works just like this : the LG CF3D projector. It's two projectors packed in one box that claims to be a single hdmi 1.4 compliant device and which does all it's left/right management internally.

However if the graphics card driver understands the concept of dual head stereo 3D, then it can use any type of connection to make stereo 3D possible, whether you use dual Single-link DVI (current dual projectors), DVI + DP, dual DP, or DP daisy chaining, it doesn't matter since the computer does all the work, knows that one display is left and the other is right and just sends the correct picture to the correct display.
And the projectors can be 3D ready or not it doesn't matter : just put the filters on the projectors, tell the driver which projector is left and right and there you go.

[Likay]

I've written to the ATi technical support to suggest them to support dual head outputs through the HD3D program but I haven't received an answer yet.

Do you have a link to the support? I want my next card to be an ati but it needs to work good!

[BlackShark]

I've written to the ATi technical support to suggest them to support dual head outputs through the HD3D program but I haven't received an answer yet.

Do you have a link to the support? I want my next card to be an ati but it needs to work good!

The usual ways to contact AMD I suppose :

The Catalyst driver feedback (no answer, only leave a message)
http://www.amd.com/us/CatalystCrewSurvey" onclick="window.open(this.href);return false;

AMD email technical support page
http://emailcustomercare.amd.com/" onclick="window.open(this.href);return false;

[skrubol]

I don't think the new Radeon's or HD3D make any difference for passive polarization (other than supporting daisy chaining over DP1.2 so you could hook up 2 future DP1.2 projectors using 1 cable.) It still takes the same software as it did before. The daisy chaining will just allow multiple displays to be fed via one cable. The computer will still see them as multiple displays.
I don't think passive polarization requires quad buffer (or it has it implicitly by having the dual-dual-buffers for the 2 different displays.)