Wrong resolution pushed to steamVR for pimax 4K?


As I understood, the input res. of pimax 4k should be 12801440 per eye (upscaled to 19202160). I used Piplay and a Pimax 4K with IL2 BoS and I noticed that images are slightly shifted to the outside for each eye, that results by a narrow black bar on inside of each eye view, and finally by a kind of black bar in middle of view, that beain can mosty ignore, but it is here. I do not have this probem with DCS or SteamVR home. As il2 BoS is very sensitive to steamVR input, I had a check of resolution displayed in “setting/developer” menu of steamVR.
I have the following information (I do not use SS at the moment, neither in SteamVR or on Piplay) : Res/eye = 1612*1989 !
Why do I have those numbers ? They are not on the same ratio : 1280/1440 = 1.125, 1989/1612 = 1.234, and 1612/1280 = 1.29, 1989/1440 = 1.38 !
My steamvr.vrsetting has no entry at all for pimax or other HMD.

EDIT1 : on top of that, it looks like IL2 BoS is not able to have the same resolution information than SteamVR, because it displays a resolution of 997x1492 for a resolution of 1209x1492 shown steamVR !
EDIT 2 : I found that if I modify IPD I also modify the resolution displayed in SteamVR ! With 50 as IPD I have a resolution of 1700x1989 and with 80 as IPD I had a resol of 2000x1989…


SteamVR doesn’t report correct resolution as Pimax is using its own renderer. Click on the gear in Pihome there is a render multiplier there.


The resolution factor is one thing and of course may change with SS factor, but normally the ratio X/Y should be the same, whatever the multiplier is.
Moreover, some games are depending of the resolution information, like IL2 BoS. I had previously a problem with the OSVR HDK2 because the OSVR steamVR component sent a double horizontal resolution, so image was deformed…some other application (DCS, steamVR home) did cope with that, but Il2BOS not.
So like for OSVR, the devs of IL2BOS will surely said that there is no problem on their side, but only on Pimax side.
I make further investigation : with IPD of 63, X res is 1612 in steamVR and 1330 in IL2BOS, and with IDP of 73 X res. is 1746 (nearly what it should be) and resol. in IL2BOS is 1455. Vertical res. is always the same. Unfortunately, IPD of 73 is not usable in IL2BOS…
So I do not undestand why changing IPD is changing the ratio of X/Y resolution given to SteamVR or game… and this is a problem at least for IL2BOS.


Okay your not understanding. The SteamVR reported resolution is not what is being sent. Pimax has its own Render multipier. You need to check piplay render multipier. The steamvr res is only used for screenshots.


Maybe I am wrong and do not see the things as they are.
But I will try to give you my point of view, so you will be able to explain me more clearly where I am wrong.
Let’s speak for IL2Bos : My understanding is that the game request target render resolution and FOV, I think by using the steamVR layer. Then it computes video frames using vertex shader, pixel shaders, and other type of shaders .Pixel shader input are in the display coordinate system, that is for example going from 0 to 1280 for X and from 0 to 1440 for Y, if this resolution is given to game.
Then the Pimax rendering is called, and make things like deformation for lens and maybe scaling, color correction,…
So image computation is made either by game and by Pimax renderer.
But if you give a wrong ratio to game, then the image computed by it will be “stretched” at the end. That was the case with OSVR/SteamVR, before it was fixed : Horizontal res. was 2 time the good one, so at the end it introduced weird deformation in IL2 BoS.
Just for information this was also the case with old version of Piplay , here is a video made by a Pimax user on this problem: https://www.youtube.com/watch?time_continue=2&v=bSnBtFyQdaM At this time I was using my OSVR HDK2, we fall on the same problem.
So, as the ratio I can read in game or steamVR is roughly at the same level than the Pimax 4K screen, things are looking OK, except that there is still these black bars in middle of view. Previoulsy (as in the video) the ratio was really different of the screen resolution, so the image was streched…
What I do not understood, is that IL2 Bos did not report the same resolution that I see in steamVR.

So can you explain me where I am wrong (and also what makes the latest versions of Piplay fix the stretching shown in video), so I will not bother you anymore with stupid questions ?


No question is stupid. :v::wink::+1::sparkles:

@sjefdeklerk knows the programming side so he might know of a fix or able to explain it better.

If you could tho plz post
Windows ver
Gpu/driver ver
Piplay ver & headset firmware version.

@Enopho might also have some incite. Now there maybe a bug related to il2 bos. Which @Pimax-Support could help with


windows 10 Home 64b
Core I5 2500K @ 3.3 Ghz, 16 Go RAM
GeForce GTX 1070, nvidia driver 388.13
Piplay, Pimax4K FW


For your information, I made it works for IL2Bos by downgrading to the 1.2.53 with an IPD of 50. Other newer version introduce black area and did not allow an IPD of less than 55…Maybe it will help devs to find the problem. I opened a ticket on IL2Bos site and the answer is that the problem is on Pimax side. And I agree because some Piplay version are working and other not !

Through lens test request: Il2 Battle of Stalingrad 3.001 update