Comparison of Vuzix VR920 and TDVision TDVisor SD prototype

[Tril]

I got my VR920 from Vuzix today. I going to share my first impressions and compare it to the prototype SD version of the TDVisor from TDVision. That's the only other HMD I ever tried. Keep in mind that I tried a prototype unit and that newer units may be better.

There's a few things I like about the VR920 and a few others I don't like.

At first, when putting it on, it sat far too low. I could only see the bottom half of the screen. The nose piece can be pulled in and out to adjust the distance between the eyes and the HMD. If you pull it out completely, you can rotate it 180 degrees and put it back in upside down. Because of the shape of the nose piece, rotating it like that makes the HMD sit higher in front of your eyes. When doing that, it sits at the correct height and I see all the displays.

I would say that the picture looks like it's at about 5 ft and about 40 inch diagonal. When I tried the TDVisor, it looked a bit closer so it also looked smaller.

I find the optics of the VR920 less straining on the eyes. With the TDVisor, it felt like I was looking through a magnifier and with the VR920 it simply feels like I'm looking at something that's at 5 ft from me.

I noticed a difference on how the inside of the HMD looks. In the case of the VR920, you barely see what's inside apart from the displays. It was not like that with the TDVisor. Light reflected off the sides and back a lot. You could clearly see the black plastic all around the displays. That's probably one of the reasons why the picture looked closer with the TDVisor. Because I saw the plastic around the displays, it was breaking the illusion of a far away screen.

I noticed something I don't like about the VR920. There seems to be some kind of reflection inside it. If I look at black and white pictures (I tried some manga scans), I see some dark red blotch/spots appear a bit everywhere. If I move the HMD a bit in front of my eyes, These spots move a bit so that's why I think it's a problem of reflection. It's possible that part of the light comes out of the displays, hits the optics and bounces back to the screens. I'm not sure what's causing it. I see it all the time and with colors too. It's worse if there is bright white in the picture. For example, if I put the VR920 on while looking at this forum, I'll see a dark red line at the right, close to the scroll bar because the scroll bar is causing reflection problems. It's been a few months since I used the TDVisor so I can't be totally sure but, from memory, the TDVisor did not have that problem.

I loaded some pictures and looked at them on my monitor and on the VR920. I would rate the color reproduction quality of the VR920 below my CRT monitor which is an hp p1230. It looks like a lack of contrast. If I increase the contrast with the wheel on the HMD, it improves the darker colors but white gets too white. I think that it might be possible to improve the colors by playing with the settings in the NVIDIA drivers. I'm not sure but I think that the colors and picture quality were better on the TDVisor.

The VR920 has a feature Vuzix calls AccuTilt®. Basically, the arms of the HMD can tilt up and down a bit. The idea is that you can tilt the HMD a bit to adjust its position. I don't like it. The idea of being able to tilt the HMD a bit up and down is good but the way it's done is bad. It would have been fine if the arms locked themselves at three positions (down, middle, up) but it does not work like that. There's absolutely nothing apart from some very weak friction keeping them from moving up and down. What that means is that when the weight of the usb cable pulls on the HMD (the USB cable is on the left side), it pulls the left side down and the right side up. This feature could be done better.

I like the shape of the lenses better on the VR920 compared to the TDVisor. The VR920 lenses are rectangular with rounded corners. The TDVisor used round lenses. The problem with round lenses was that it was easier for the lenses to hide the corners of the displays. On the TDVisor, I could not see the corners of the displays and on the VR920 I see them. The nose piece was not adjustable on the TDVisor so I could not place it closer to my eyes to see more of the displays.

I noticed something with the VR920. I see the two displays not centered. They are a bit to the left. I could fix this by moving the HMD a bit sideway. My guess would be that maybe my nose shape is not perfectly centered between my eyes or the HMD is not perfectly straight. There's not much I can do about that. The nose piece is not adjustable sideway so I can't really move the HMD sideway.

I did not test stereo in games because I'm on Vista 64 bits right now and Vuzix does not have a USB 64 bit driver available. I tried some stereo screenshots and the stereo effect works well.

From what I've seen, an HMD in stereo is not as impressive as a big screen in stereo. On a big screen, you can display stuff that's close to real life scale and when you get pop out, it's really impressive because you get the impression that the game is really coming out of the screen. You don't get that feel with an HMD. However, there's something on an HMD that you can't get on a big screen. It's how headtracking feels. You can use headtracking with a big screen but it won't feel the same.

I wear glasses (myopia) and I can wear them just fine with the VR920. I tried with and without my glasses and I can't use the VR920 without them because I see too blurry without them. It worked fine with glasses too with the TDVisor.

The intraocular distance can't be adjusted on the VR920 but it's fine. It's not totally perfect for me but it's very close to what I need. It was fully adjustable on both eyes on the TDVisor and that was a nice feature. This is also nice for people that have a nose that not perfectly in the middle of both eyes as they can adjust the two eyes sideway.

The VR920 is smaller than the TDVisor but that's not important.

The VR920 comes with a pouch that can double as a cleaning cloth. That's nice. The TDVisor did not have that.

The VR920 uses two arms like glasses. They are tight so they keep the HMD firmly on your head. The TDVisor used a headband. I liked that a bit less. It required a bit too much tension for comfort (pressure on the nose) to keep the HMD solidly in place.

The VR920 only uses one input and I like that because I can put my dual head video card in clone mode and see what's on the HMD on my monitor at the same time. The TDvisor requires two inputs and you need an external box to connect two monitors at the same time (not included). I found that annoying because it required me to boot while having the HMD connected and I needed to close my left and right eyes while playing around in Windows to look with only one eye at a time since the picture of each eye was different. The TDvisor was 800x600 and it required Windows to be set to that resolution. The VR920 is 640x480 but I can leave Windows at 1024x768. I like that better. Windows is not made to be used with a resolution of 800x600 anymore. A lot of menus get cutted because they are too big. It would be nice if the TDVisor could accept at least 1024x768 and did some scaling in their blackbox. If they could do some scaling in the black box, they could also experiment with putting a button on the HMD or blackbox that scales the two inputs only horizontaly to resize their width by half and then displays these two scaled pictures side by side on both eyes. This way, you could put your computer in dual view in Windows and be able to see both inputs at the same time without having to close one eye at a time. I'm not sure if it's a good idea because of the distortion this would cause but it would probably be less annoying than close your eyes all the time to switch to the input you want to look at while navigating your way in Windows.

I did not try the microphone and the headphones.

That's all I could think of for now. I did not test any games because I want to test them in stereo and I have to install XP first.

[LukePC1]

wow interesting review. I'm looking forward to the real 3D and headtracking part

[Freke1]

Great stuff
I have a lot of questions, but they could be summed up into one:
Is it something You would play the newest games with?

[yuriythebest]

I'm very excited aboud their stereocamera. Hope the price will be decent in the under 300$ range.

[Tril]

I took some picture of how it look in the VR920. Keep in mind that it's a bit less blurry than that on the VR920. Blame the camera and my photo skills.

Assassin'c Creed screenshot : http://www.mtbs3d.com/gallery/displayimage.php?pos=-855
Reflection issue : http://www.mtbs3d.com/gallery/displayimage.php?pos=-856

[stee1hed]

Tril, awesome review!

I am going to be getting a new TDVisor either later this week or early next week. They just asked for my phone number for shipping.

I would like to contribute to this thread with my impressions of the TDVisor and some pics to see if they may be the same as what you remember, better or worse.

I currently have an XP system with an AMD 3500+ and an ATI 850x dual output video card (older system) that I will be able to test right away using the new iZ3D driver. Late next week I should be receiving my new Dell 1730 laptop that has Vista, Intel Core Duo 2 Extreme and SLI nVidia 8800 GTX. I will be using this with a Matrix dualhead2go setup to hopefully enjoy the power of SLI in stereo.

Your comments about 800x600 support scare me. We'll see how it goes!

[Tril]

stee1hed, do you have a VR920?

Don't worry about 800x600. It was not that bad. I had lots of icons on the desktop and many installed programs. Because of that, not all my icons were shown at 800x600. Also, the Start menu was also only partially shown. It's that kind of annoyances that happens with a desktop at 800x600.

I installed Vista 32 bits because the stereo driver does not work in Vista 64 bits. It works properly in Vista 32 bits. The only games I tested were the two free demos included with the VR920 and Crysis.

I think that the picture quality of the displays is a bit better on the TDVisor. One factor that plays a big part in this, apart from the difference in resolution, is probably that the TDVisor uses LCoS displays while the VR920 uses LCD displays.

On the VR920, sometimes I notice some kind of shine on the displays. It's barely noticeable. It's the kind of shine you can see on LCD monitors. I can't be sure but I think that you don't see that with the TDVisor.

On the VR920, I can sometime see black lines between the pixels. The first time I put the VR920 on, I thought it felt like using an SNES emulator with a TV Mode effect added. Now, I don't see that anymore. Maybe I imagined it or I got used to it.

I noticed something strange. There seems to be a color problem in only one eye. In the right eye, the picture is perfect. In the left eye, I can see a problem with the colors. I don't know how to call that, it's like that eye uses less colors so it looks grainy. This might be why I thought the displays were shiny. An artifact like that is uncomfortable in stereo because only one eyes sees it. Maybe it's the 24 bit problem I've been hearing about.

After testing the VR920 in Crysis, I can say that there's one thing I don't like. It's the low resolution. It's a very well done HMD but in the end, at only 640x480 per eye, it just can't beat the picture quality of my current CRT monitor. It might still be enjoyable. I'll have to play with it a longer time on more games.

There's some noise displayed on the VR920 but there was also some with the TDVisor. My guess is that it's because it's analog and the cable is lightly shielded because it need to be small and light.

The stereo effect works really well, in and out of the virtually far away screen.

The headtracking worked for the first evening when I got it (if I'm remembering correctly). After that, I could never get it working properly anymore. When I move the VR920 in the pitch or roll direction, it also detect yaw change. So if I look up or down, it also turns my head. Same thing happens when I roll it.

In the end, I think I'm too picky about picture quality to truly enjoy HMDs. To answer Freke1, I'm not sure I would play the latest games on it. If the color problem in one eye gets fixed and if the headtracking worked better, it would be more enjoyable.

[crim3]

There seems to be a color problem in only one eye.

The problem with HMD's is that both display have to have the same brightness, contrast and color response, otherwise it can be very uncomfortable. Maybe the vr920 software allows that kind of settings for each display. I have spent quite time making both displays work equally with the z800.

Headtracking is essential with a HMD, I'm still waiting for the ultimate tracker. At consumer price, of course...

[cybereality]

I've got a VR920, its decent quality nothing spectacular but still cool. It requires a bit of work to get it configured properly on some games, but works well when it does.

In terms of the discrepancy between screens, that can be adjusted (slightly) via the OSD if you hold the volume button on the unit down for 5 seconds. Theres an icon that looks like 2 eyes. You can move this back and forth to tweak the brightness for each eye. The colors can be tweaked in the nvidia display options to get a slightly better picture. Also, make sure to update to the newest firmware, I believe it supports 24-bit color (instead of 16-bit) and includes better stereo compatibility with some games (XP/Vista 32-bit only). The headtracker can also be tweaked to reduce the cross-chatter between axises. Its not perfect, but if you fiddle with it for a while you can almost eliminate the issue. Its probably not going to be as accurate as if it had a global position sensor (like TrackIR or the Wiimote) but its a pretty decent solution considering the price.

[stee1hed]

I do not have a VR920. The only other hmd experience I have is with the original i-glasses and a game called 'aladin's carpet' down in Disney World. I did try the TDVisor when I was over at TDVision of course and liked what I saw.

They have plans for a 720p version in the 4th quarter (current goal) which is exciting and I'm hoping that my contribution helps them achieve it. It is what many people are waiting for, the high res version. They may have a budget for an hmd but don't want to buy the 800x600 knowing the 720p version is around the corner. But this is hurting TDVision somewhat because there is some lost revenue due the people holding out. TDVisions fault for releasing this info to prematurely and they have admitted that.