Forewords:

A little bit about me, so you know who is testing and why it’s not just another impression review. Impressions are not enough, content that allow clear comparison for precise testing is key.

I am open to any conversation on Social media (Twitter, Facebook and Reddit), where I posted links to this.

Why do I spend a lot of time on this? because I want VR to succeed, improve and have Pimax and other release some great Hardware/software. Pimax is a small team, trying to tackles very hard problems…

Skip the 2 next paragraphs to get directly to the review.

About me, a +5 year full time VR Dev:

Indie dev for about 20 years, working on my own projects since 2010, Oculus Kickstarter backer in 2012, when that was successful, I immediately started thinking for VR. When my DK1 arrived in May 2013, day 1, I was in VR in my Universe. Since then I’ve been a full time VR dev, reaching out to the VR community and meeting them finally in RL at SVVR conference in May 2014. I live in and for VR, creating my own Universe. I own pretty much all the relevant Hardware, have a very technical eye on both hardware and software. I am just not a programmer(I use Unreal Engine 4 and blueprint).

I am backer 134 of Pimax, reached out to be a tester,but that didn’t went through. (They think it’s better to give test hardware to YouTuber than devs… it’s a promotional thing… and that’s ok, there are some great reviews there but none -that I know of- from a full time VR dev that has been immersed in his own content for +5 year on pretty much every VR hardware available)

I tried StarVR a year ago in Tokyo, I do not own a Vive Pro or an Odyssey, as the audio sucks terribly and is no fit for my musical Universe, the Odyssey is not legally available in France, and I try before I buy. No try no buy.

Hardware, software installation:

Great reviews from the YouTubers out there, go check them out. (Unboxing and all)



Hardware in a blink:

It’s super light and that what impressed me first, then the strap attachment to the HMD is… a failure waiting to happen, it’s going to break.

Long Cable in a big living room: Vive length!

The strap on the side, the part where it connect to the harder part just hurt my ears, that’s not good, also the cable pass should be the other way around so it’s softer on the head side!

Let’s install:

My PC is a workstation, Dual CPU server motherboard, 8 Core Xeons, 64Go or Ram and a Nvidia GTX 980ti running « last month drivers/October » V.416.34

Vive setup is using Knuckles EV3 (paired to Pimax! but recognized as Regular Vive wands), and Vive « Pre » Lighthouse (V1), using SteamVR Beta latest.

Drivers:

It was hard to find the PiTools and driver, no sticky post on Pimax 8K forums and Pimax Website is just a 404 mess.

http://pisetup.pimaxvr.com/PiToolSetup_1.0.1.84.exe

http://piplay-us.pimaxvr.com/PiToolSetup__90.exe

Install the latest right driver? WRONG!

Installed naively the lasted, it rendered my workstation unusable, with a rain of errors popups, Pitools.exe making multiple copies of itself overflowing the Task manager… impossible to kill as they re-poped indefinitely. I had to hard reset my PC and « disable PiTools on startup », my PC was uncontrollable and frozen overwise.

After an Nvidia Update to October and Window update to the latest, same thing.

The solution was to roll back PiTools drivers to 1.0.1.84.

That worked.



The HMD was not recognized in Pitools… I had to unplug the HMD, replug: USB driver installation finally kicked in and it was all GO.

And this is where everything is confusing:

You can use PiTools or… not and boot directly SteamVR.

But on Steam VR you won’t be able to tweak FOV to their Small/Normal/Large FOV. (Change is immediate in the HMD, so that’s pretty cool), The rendered resolution is not, that setting needs a restart from the VR app you are using (UE4 in my case)

3DOF???

I run room setup, both from PiTools and steamVR, my HMD was stuck on the main Lighthouse.

Tried everything, once more Reddit community had found the fix:

Delete a folder in (C:\Users\Administrators\AppData\Local\Pimax\runtime\config\lighthouse),and then restart the PiLauncherService »

OK! All go! Let’s fire up Unreal Engine and Synthesis Universe with Pimax large FOV!

Link start?

56 fps… SU content is light, barely any texture/normal maps, so performance has never been an issue, back in May 2014 my PC demo was running flawlessly on Morpheus (PsVR).

Forward rendering, no RT shadows, true low polys.

Empty Scene, full black, no geometry: 70fps darn! My 980ti can’t handle well regular PC gaming at 4k, so no surprise)

SU latest demo (The one for OC5) runs at FPS 35-60…

Ok for me to Dev, definitely a no go for release, but a black empty scene is running at 70fps (it should be 80-81fps) not much I can do but buying a new GPU.

(I refuse to buy one for now because of the scandalous « ti » pricing that nearly doubled from the previous generation!, 1080ti are still pretty much the same price as the 2080… so yeah no thanks!)

Visual quality:

Screens: pixel density, gate, contrast, mura and all…

It’s good enough, (once again check the YouTubers reviews), for me it’s « good enough », it’s a great improvement to Rift/Vive (non pro), Backs are also good enough, and colors are… good! my content didn’t shift to another range of colors, 8K visual quality is similar enough.

I am happy so far.

And then you turn your head…

IPD?

I was always pretty much insensitive to current HMD IPD settings, on the pimax you must have it perfectly set to yours. I had mine measured by an optician.

And fun fact you should know, IPD is asymmetrical… so the center between your eyes is not your face center… so that’s is why Eye tracking and correct use of IPD is very hard. With bigger FOV like the Pimax… well:

Horizontal FOV:

Immediately I noticed on the edge of my outside FOV some super funky distortion and a sort of bright line…

The outer Fresnel ridges take a big light accumulation and reveal an arc of brightness, definitely distracting.

The distortion is off, horizontally there is some stretching going on: put the object in the center of your view, rotate horizontally so the object move to the side of the screen and keep your eyes straight to the screen: The object will squeeze and then grow while fading in a mix of lens blur and chromatic aberration, adding on top of that the bright arc of light.

This effect is super distracting and kill the whole experience at if give you the sensation you are dragging the side of the outer screen with you when you rotate… not… good.

Vertical FOV?

So here’s the thing, when you press your face to the lenses and look down (or up) you can see the bottom/top of the screen: you notice a LOT of pixels that you don’t see ever normally: a LOT are rendered and wasted, there is probably nearly a centimeter off screen. (+half an inch)

The distortion are even more impact full as the horizontal one as it’s compressed over a smaller (vertical) FOV

It showed me object on the ground bigger than they are if I don’t look directly at them (The Robot Drone docked in the ground).

This is super distracting… it’s even more than that… it’s motion sickness inducing as the whole ground feels wobbly/unstable.

It’s that the other screen I see with my other eye?

Yes it is…: super distracting I can clearly see « a finger thickness » of the my left screen with the right eye… and I absolutely shouldn’t.

I do have a big nose with a consequent nose bridge, so I am in the range of people who shouldn’t have that problem at all. (With one eye I can see both screens/lens!)

Chromatic aberration « C.A » … what are you doing here?

When looking at the SU title I can see it completely with both eyes, I designed it that way for Rift/Vive so it’s possible to read it without turning your head.

It’s at a comfortable 7m distance. (« 700 » in UE unit)

Here the problem: I can’t see it fully clear without lenses blur or chromatic aberrations (Same as Rift and Vive, but I was not expecting that issue on Pimax large FOV):

The Green and Red are « Photoshoped crappy estimate), but it give you a good view of the problem: One eye see it nicely with some C.A. near the nose bridge area. So in the end because of that, looking straight, both outer side of non eye overlap are with too much C.A and lens blur, it makes the title not looking as great as I though it should with a « 200 » FOV.

Lens Blur and sweet spot:

Continuing with the title in front of me, looking straight and turning my eyes all around, there is not much that is not impacted with lens blur.

That blur is the same one that you have on current HMD: it’s a current technical/optical (quality) limitation, only most of the center of the lens is perfectly clear.

I was expecting an improvement over Rift/Vive, but it’s exactly the same and for a good reason: it’s the same base tech.

Reducing FOV:

Normal FOV nearly get rid of the edge distortion, enough to make it usable, Small totally get rid of that issue, but it feel a little too much restricted, better than a Rift/Vive, but feels like a waste, using your racing car to go food shopping…

With Small FOV you are left with a clearly better FOV than Rift/Vive but exactly the same optical blur/C.A problem.

Rift/Vive back on:

And then…. OUCH o_o the FOV hit you so darn hard, back to tunnel google vision… you want to go back to Pimax FOV, but then you remember that… it’s just that, a bigger FOV with the same lens blur, Fresnel lenses (I hate them all) and the same chromatic aberrations…

You want Pimax to be good, but it’s… not.

I want my Pimax!

Delivery is a mess but they have a new guy and production is ramping up, far from the « all back for X-mass » so be patient and fill your info here to help relief everybody stress:

https://docs.google.com/spreadsheets/d/1sK1w_-gU6LaPYmZF1B-5W-Mr7gC1pFTuGkv2WBrQr-Y/edit?usp=sharing

What if you are:

…a backer! I just pre-ordered!

Be patient, if you are a higher back number you should have a better experience than I have, as the diver/software will improve over time.

…a dev!

You don’t need Pimax, it’s more trouble than problem solving: you need your UI to work great on small FOV and not just on Pimax.

Testing performance is just impossible, Pimax is kinda hacking SteamVR, they use different rendering resolution with different drivers, these are constantly changing setting/ratio, so no way to measure your content performance.

Final thoughts

What Pimax is trying to achieve is brave, that is also a synonym for useless, why don’t we have larger FOV (140-150) HMDs releasing very soon, even as DevKits? Because the tech is not here.

You could push FOV to 140-150 if you have some very good R&D and top people in the field, going beyond that is just not doable using the current combination of flat screens, and a set of Fresnel Lenses. You need much more, you need eye tracking, very advanced optics and some great software.

It won’t work without having the HMD calibrating with the user eyes (Through eye tracking cameras).

Pimax is trying to do something not possible with the tech they are using. You take a Rift and a Vive and try to push their FOV and that is exactly what you will get: failure.

You probably could do it for 1 user, having the full pipeline tailored and calibrated for him, but consumer HMDs need to be good for « 98% » of your users.

The pimax is looking exactly like a Rift/Vive on steroid.

It’s showing the optical limitations of the current tech in combination of software compensation for distortion and chromatic aberration.

With the current software implementation, and low FPS it’s definitely for me not worth Deving VR on it, I’d rather continue using my Rift.

It’s all sad really because I want Pimax to be good, FOV has always been for me a much bigger problem than resolution, I remember having presence in some great Dk1 demos, but FOV is really my 1st wish.

Pimax is like that thing you want, you want to believe it’s a usable HMD that will replace your Rift/Vive, something good enough to be Gen 1.5 or even 2!

With every VR hardware: when you try something better, you just can’t go back, on any aspect, Pimax shows you an amazing FOV, but the distortion correction is not compensated correctly, showing the limit of what is possible with that current (outdated Rift/Vive) technology.

You could very probably, if you are Valve or Oculus make a 140-150 ish FOV without Eye tracking, better resolution, less optical issues and great software, but that’s about it. Not much better.

Read this as a reference:

« Analysis of eyepoint locations and accuracy of rendered depth inbinocular head-mounted displays »

True Gen2 will need to be much more than that.

Edits:

(Nov13th): « Pimax shows you amazing FOV, but the trade off for all the rest, the fact that it doesn’t improve anything else make it not the right solution using that current (outdated Rift/Vive)technology. »

Changed to:

Pimax shows you an amazing FOV, but the distortion correction is not compensated correctly, showing the limit of what is possible with that current (outdated Rift/Vive) technology