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My new 3D projector works great except slightly out of sync

Posted: Wed Jun 29, 2011 3:24 pm
by 3Dfun
Hey everyone.
I'm new here, but not brand new to 3D. I used to have an old DLP projector that I ran at 60 Hz with an old edimensional setup and stereoscopic player and it worked great other than the dark image and flickering. I finally upgraded to a 3D projector. I love it because it's completely flicker free! The problem I'm having is that it seems the left and right eyes are a little off- it looks like by just 1 frame. I don't know if this is normal when using a 3D projector. My wife and my kids don't notice at all, but it bothers me. It reminds me of those old 2D to 3D conversions where the left eye was put 2 frames ahead of the right to create a fake "3D" effect but it makes you feel disoriented after a while because one eye is constantly ahead. That's how I feel with this projector, but not as extreme. The picture is perfect when its still but when anything pans horizontally, that is when I see it. It is visible without the glasses as well. So, here is what I have:

X1161P Acer 3D Projector connected via VGA
DLP LINK glasses
Radeon X300 graphics card on a Dell dimension PC
I'm viewing side by side (1280 X 720 squashed) material on stereoscopic player in pagefilpping mode

One other thing to note- I can't set my graphics card to 120 hz. It doesn't even have the option. It only goes up to 85.... so I set it to 60, but the projector itself obviously displays 120 hz though because there is NO flicker.

If the problem is with my graphics card, I'm happy to buy another card. I just want to make sure if I buy something, it will fix the problem. Again, I'm new here, so if I'm posting in the wrong forum, just let me know. Thanks in advance for the help!

Re: My new 3D projector works great except slightly out of s

Posted: Wed Jun 29, 2011 8:52 pm
by cybereality
Hey, welcome to the forum!

Unfortunately I do not have much experience with projectors, I just know that they can be problematic (except for certain models, like the ones certified for Nvidia 3D Vision). And people have complained about 1-frame lag issues, specifically with 3D gaming drivers, for video I know it can be an issue with dual projector based systems. In addition, software page-flipping in the Stereoscopic Player can be unreliable depending on your setup. But clearly you got it to work to some extent.

I honestly don't know the solution, but let me through some things out there. Make sure you are running at the native resolution (800x600). If you use other res, then the unit will have to scale it internally, and this could be adding lag. Try to see if you can get it to run at 120Hz somehow. I see that some other people have got 120Hz to work a 800x600 resolution. Its possible maybe even the video card itself doesn't support it (not sure) or maybe you need to install the driver for that particular projector. Also, if you buy a 5000/6000 series AMD card you may be able to play games in 3D using the IZ3D driver in 120Hz mode. But I cannot say for sure if its the card, although new cards can be cheap. Though that computer sounds really old, would it even support a modern card?

Re: My new 3D projector works great except slightly out of s

Posted: Thu Jun 30, 2011 6:39 am
by Fredz
I have a similar setup in my living room, a Dell Dimension 4600 PC with a GeForce 7600 GT and an Acer X1130P 800x600 DLP 3D projector, using eDimensional and Elsa Revelator glasses. I'm using the old NVIDIA stereo driver on Windows XP and it does work quite fine.

Your Radeon X300 GPU should be able to support 800x600 at 120Hz without a problem, if it's not the case it's a problem with the driver for the projector as Cybereality said. It may also be a problem with the EDID that is not read correctly on the VGA port, in this case you could try to connect the projector to the DVI port of your GPU with a DVI->VGA adapter if you have one.

If you are using Windows XP on this PC, my advice would be to buy an older GeForce GPU (<7950 GTX) which will be compatible with the old NVIDIA stereo driver. You should be able to find one at quite a low price (around $20/$30 or maybe less).

Re: My new 3D projector works great except slightly out of s

Posted: Thu Jun 30, 2011 7:00 am
by crim3
3Dfun wrote:...
The problem I'm having is that it seems the left and right eyes are a little off- it looks like by just 1 frame.
...
I think that you are perceiving the problem that it's inherent to shutter-glasses. I noticed it very much on my own setup. Image is all fine but when I move the game's camera, I can feel the difference between the eyes. Things change while one eye is shut, so when it opens the image is a bit different to what the other eye was seeing.
Anyway, my experience is with games. I see you are watching movies. My guess is that the same frame should be sent to each eye, so I'm not sure if the problem you see is the same that happens with games.

Re: My new 3D projector works great except slightly out of s

Posted: Thu Jun 30, 2011 10:42 am
by 3Dfun
Hi everyone,
I REALLY appreciate the help! I should have mentioned also that I'm running Windows 7. Will Nvidia drivers work with my ATI card? I'll try setting the resolution to 800 X 600 and report back. Thanks again. You have all been VERY helpful!

Re: My new 3D projector works great except slightly out of s

Posted: Fri Jul 01, 2011 12:39 am
by crim3
No way they can work with ATI cards.

Re: My new 3D projector works great except slightly out of s

Posted: Fri Jul 01, 2011 6:37 pm
by cybereality
I think the problem is likely that its not running 120 Hz . But keep in mind that shutter glasses in general will always have issues with panning shots. This happens because the eyes are not viewing at the same time. In this way passive will always be better.

Re: My new 3D projector works great except slightly out of s

Posted: Sun Jul 03, 2011 11:08 am
by 3Dfun
Hello everyone,
Thanks for the help! Here is the latest:
I set the resolution to 800 X 600 and now I CAN set it to 120 hz. I was encouraged until I tried to run a movie with stereoscopic player. When I double click on the screen, it now CHANGES the refresh rate to 85 Hz and the image shakes back and forth from left to right eye (3D does not work- this shaking is visible with or without glasses) I can't seem to get it to stay at 120 Hz when I enlarge to full screen.

As far as the shutter glasses thing, I understand what you're saying- the timing is going to be slightly off because of the alternating left eye right eye technology, but at 120 Hz this should really not be that noticeable. Even the real D theaters use one projector with alternating left eye right eye (with the active element being the polarized filter rather than the glasses) and you can't see any delay from right eye to left. The fact that I can SEE the delay from one eye to the other WITHOUT the glasses makes me think that is has something to do with either stereoscopic player, the projector or my graphics card I've been watching 3D with shutter glasses for years without this problem both on CRT TVs and my old projector (running at 60 hz) so it seems like it's some kind of problem with the graphics card not being able to display at 120 hz.

Do you think if I changed to an nvidia graphics card, this would be solved? Thanks so much for everyone's input. I really appreciate it!

Re: My new 3D projector works great except slightly out of s

Posted: Sun Jul 03, 2011 11:17 am
by cybereality
The problem with Nvidia cards is that the driver is designed to only work with Nvidia "certified" displays. Since your projector it not on Nvidia's list, there may be issues getting it to work. So you will probably have better luck with AMD. Something on this list: http://www.amd.com/us/products/technolo ... dware.aspx" onclick="window.open(this.href);return false;

Its still no guarantee it will work, but its worth a shot.

Re: My new 3D projector works great except slightly out of s

Posted: Tue Jul 05, 2011 1:30 am
by crim3
I have had a passive display for a couple of years, and now that I'm back using shutter-glasses, I notice the effect a lot even at 120Hz. In this 3D hobby it seems that when you want to improve in one area there is something to give back. Now I can enjoy a 80" screen that covers about 70 degrees of field of view, but I'm all the time missing the smoothness of the little 22" passive 3D display.

But I'm not sure if the effect I describe is the same you are describing as I'm talking about gaming and you about movies.

Re: My new 3D projector works great except slightly out of s

Posted: Thu Jul 28, 2011 10:49 am
by 3Dfun
Hey everyone,
I'm not sure if people are still checking this thread, but I wanted to give an update.

I bought a new graphics card- a GeForce GT 430. Same problem. Then I read up on the quad buffering open GL pageflipping mode in stereoscopic player and decided to give it a shot. I bought a quadro card... same problem- actually, more problems (which I won't go into since they are not relevant to my original point)
So, I've concluded that possibly this is just the way it is when viewing in pageflipping mode. As a side note, I think SOME of the effect I see comes from the shutter glasses. If I view a 2D movie with the shutter glasses on, I still get some of that "false stereo" effect, but that's not the main thing I'm referring to. The main thing I notice can be seen with or without the glasses on- particularly when there is horizontal movement. It is a bit of a jerkiness like one eye is just slightly behind the other. Perhaps this is just the nature of 3D in this mode, but I'm wondering if it would help if I could set the display to 120 hz. When I change the resolution to 800 X 600 I can set the output to 120 hz, but when I put stereoscopic player in full screen, it defaults back to 1280 X 720 (probably because this is the resolution of the movies I am playing)

So, here is my new question. I'm willing to give this one more shot. I've read that VGA cannot support 120 hz at 720p resolution, but HDMI can. Would it be possible to convert HDMI to VGA and still acheive this? The GeForce GT 430 has an HDMI output. If anyone thinks this will work, I'd like to try it. Please let me know your thoughts. You've all been very helpful. Thanks again!

Re: My new 3D projector works great except slightly out of s

Posted: Thu Jul 28, 2011 10:54 am
by tritosine5G
I've read that VGA cannot support 120 hz at 720p resolution, but HDMI can. Would it be possible to convert HDMI to VGA and still acheive this? The GeForce GT 430 has an HDMI output. If anyone thinks this will work, I'd like to try it. Please let me know your thoughts. You've all been very helpful.
not quite, VGA can do fullHD at 120hz while hdmi can't :D

Yes you should try VGA , they refer to it as "the generic CRT mode" with pulled pin, like they did it with QUMI:

http://www.avsforum.com/avs-vb/showthre ... 75&page=38" onclick="window.open(this.href);return false;
read this forum , how they made it work thru VGA,
quality should be the same as thru hdmi.

Re: My new 3D projector works great except slightly out of s

Posted: Thu Jul 28, 2011 2:23 pm
by 3Dfun
Hello,
Thanks so much for the quick reply! Yes, through VGA I can do 720p no problem. The problem I'm having is that I cannot set it to 120 hz. It will only do 60 through VGA. I'm wondering if going from HDMI to VGA will allow me to set the display to 120 hz within the control panel. I know it's a long shot, but I can't seem to get anything else to work. Obviously I don't want to buy one more thing if it won't work, but I am curious. What do you think?

Re: My new 3D projector works great except slightly out of s

Posted: Thu Jul 28, 2011 3:03 pm
by tritosine5G
find that post with the "success story" , you need a VGA adapter, and pull pins!

Without pulling pin , you won't get to CRT mode, OS won't treat your PJ as a CRT ( no native resolution / refresh).

Re: My new 3D projector works great except slightly out of s

Posted: Thu Jul 28, 2011 3:33 pm
by Fredz
tritosine2k wrote:not quite, VGA can do fullHD at 120hz while hdmi can't :D
I'm not sure the VGA connector can support fullHD (ie. 1920x1080) at 120Hz. And even if it was supported, you would need a display or a VGA converter able to support this resolution/frequency.

From what I've read on the Web, 1680x1050 seems to be the higher resolution supported in VGA at 120Hz (306 of the 400 MHz of VGA bandwidth). At higher resolutions the noise could be a problem and the image quite degraded, 720p at 120Hz should be no problem with VGA though.

Re: My new 3D projector works great except slightly out of s

Posted: Thu Jul 28, 2011 4:09 pm
by 3Dfun
Thanks again for all of the insight. I'm looking at this page:
http://www.avsforum.com/avs-vb/showthre ... 75&page=38" onclick="window.open(this.href);return false;
I cannot find a post titled "success story." Am I on the right page?
I am now thoroughly confused. Is the maximum refresh rate determined by the card or by the display? The reason I ask is because I've been through 3 different cards (2 that were specifically made for 3D viewing) and none of them will allow me to choose anything greater than 85 Hz. 2 of them will only let me choose 60 hz- it has no other options. I cannot for the life of me figure out how to choose 120 hz at 720p.

Thanks again for everything. You guys continue to be tremendously helpful and I am learning a lot. Thank you!

Re: My new 3D projector works great except slightly out of s

Posted: Thu Jul 28, 2011 4:51 pm
by Fredz
GPUs can easily support 120Hz, if you can't setup your graphics card for such a frequency that's because the display doesn't send back information about a supported 120Hz mode via the EDID pin for the resolution you selected. You should try to use the native resolution of your projector when setting up a mode with the 120Hz frequency, in this case 800x600 for this particular model (Acer X1161P).

Re: My new 3D projector works great except slightly out of s

Posted: Thu Jul 28, 2011 8:18 pm
by 3Dfun
Hello,
Thank you for the reply. I've tried 800 X 600 and it will let me set it to 120 hz, but as soon as I put stereoscopic player into full screen mode, it reverts back to 1280 X 720 (at 60 hz). Is there any way I "force" 120 hz at 1280 X 720 even though this is not the projector's native resolution? Thanks!

Re: My new 3D projector works great except slightly out of s

Posted: Thu Jul 28, 2011 9:40 pm
by Fredz
You shouldn't force a 1280x720 mode if the native resolution of your projector is 800x600, the image will be degraded if you do this. You'd better find out why Stereoscopic Player switches to 1280x720 when it enters fullscreen. If you are using the NVIDIA 3D Vision viewing method you should be able to force a particular resolution in the Advanced Options of the player or directly in the 3D Vision settings.