Hello
Anyone who can answer why Pimax produce headset that not use the native input resolution.
I refer to 4k 5k and 8k.
Regards
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5k(+) does. 1440p input and display. The others use an upscaler which means that in theory you can have a lower gpu load to generate the image but a screen with more pixels and less screen door effect (SDE).
In reality the upscaler means more blurry images unless you increase the supersampling level of the image before sending it to the device, therefore increasing the gpu load compared to a panel with a native resolution the same as the input
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DP limitations on the 8k does not allow 4k input/eye on a single cable. This is why the 8k-X will have a dual DP cable.
The 5k (2x1440p) is around the limits of DP 1.4.
The pimax 4k model at the time of manufacturing was limited to hdmi 1.4 specifications & that of it’s bridge chip.
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Ok I understand.
Thanks for the answer.
But could not the 2080 manage the native resolution on 8k if you decrease framerate.
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Well the answer is yes, but the bandwidth of a single display port is not enough. The 8kX will use two display port for this reason. This will be natively taking and displaying the full resolution without the upscaler. The problem is that this requires a really powerful gpu to keep up with 80 or 90hz. Basically not on be that really exists yet. However there are some technologies that could help with this such as brainwarp which is currently in beta and something called covered rendering where we only render the part where your eyes are looking at at high resolution and the rest at a lower one. The latter of these needs a lot of things to come together, such as eye tracking, gaming engine updates, gpu driver updates and libraries so that’s still quite a way off and would need to be explicitly supported by the game.
We are expecting brainwarp from pimax in the next few weeks. This will do a clever trick to smooth out missing frames so instead of needing 90 fps to be smooth you can get away with 45.
Edit: Full frame will never be possible with the 8k because the hardware will not allow it. This is for the 8kX in the future
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The best way to see why you supersample is to run a game feeding native resolution to the headset and then run it again with supersampling. You will see why.
It’s an incredibly effective form of anti aliasing for vr. Everything looks better. Despite same number of pixels being shown in the end.
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Ok ,but i guess it will always be better with native resolution on the 8k than ss.
So it is basically the GPU and not DP 1.4 that limit this.
If I do a simple calculation the needed BW for 8k sensor is 384021602908= 12Gb/s (90Hz and 8 bit colour)
The spec of DP 1.4 is 25,92 GHz.
No that’s confusing two different things, which is my fault for going off into super sampling when others are discussing feeding the final signal at native resolution vs upscaled.
I just added my super sample comment as that’s how I read the title and assumed others would click it thinking the same as me.
Super sampling is early in the process where the game draws the frame to be displayed eventually after other stuff happens (you can see my technical prowess here). Drawing this much bigger than the final frame you will send has much benefit. It looks way better. You definitely want as much of this as your rig can give (up to a point anyway).
The other issue is the final signal to be passed to the headset which is what people here are discussing. The 5k gets 5k worth of signal sent and displays 5k of info across 5k. The 8k gets 5k of info and displays 5k of actual info across 8k and makes up the bits of information in the missing part. So if you could feed 8k to the pimax 8k (8kx) it would be better because it’s not just making up the stuff in between.
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I am with you 100% Flinnt.
Hope anyone could answer what really limit to have native resolution on 8k.
My calculation of the BW may be wrong.
Possibly but then your making the min spec 2080 & at say 60? Refresh which would likely not produce a desireable experience as many are likely to experience vr sickness.
And the scaler may need to support the higher res at lower refresh rate.
I think the 8 bit is per individual colour and there are three colours, red, green and blue for each pixel so you need to multiply your BW calculation by 3
Yes you have basically right , the normal colour deepth is 28 or 30 bits, but I doubt this is really needed in gaming.
Any way if you look at the spec for DP 1.4 it support:
“Using DSC with HBR3 transmission rates, DisplayPort 1.4 can support 8K UHD (7680 × 4320) at 60 Hz with 30 bit/px RGB color and HDR”
But this is only valid if the display support the coding DSC that reduces the speed up to a factor 3.
If the displays used in Pimax support this it shopuld be possible to transmitt data with 90 frames / second to a 7680 times 2160 display with DP 1.4.
On the other hand if the display do not support DSC you could go down in framerate or colours to transmitt the data. Gaming requires less colours, film requires less framrate.