"World moving with you" phenomena. What, Why and Fixable?

What
So @mixedrealityTV and @knob2001 have both mentioned seeing this on the HMD’s. MRTV says it is on the 8K and describes it as a kind of wobble effect that follows your head movement. I was under the impression that @SweViver or @mixedrealityTV agreed this was fixed in a PiTool update?? but @knob2001 disagreed in his Spanish review so it would appear this is not the full picture (Around and around we go!) and now we have Seb saying it is still there or has come back.

Why
After trying to find out what this is I came across this thread: https://www.reddit.com/r/oculus/comments/6dhxgr/can_someone_explain_why_oled_is_superior_to_lcd/

And the first comment mentions this as ‘floating’ on slower displays. The 8K is 80Hz which is why maybe it is visible on that unit and not so much on the 5K which is 11Hz quicker. It is just not low-persistence enough.

If you read further down then Eric goes into more detail about the problem saying it is our retina that creates the issue due to the slower panel speed.

Fixable
if they can speed that panel back up to the same as the 5K+, however there might be a sacrifice somewhere else . e.g. redirect backlight power to the panel which would lower the 8K’s contrast. Also, the Hz issue is a long standing one so would appear to be very difficult to fix.

It would be good to hear from @Pimax-Support if there is any hope of a fix for this issue.

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That 80Hz is not a panel limit. It is the limit of the scaler.

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How is that limit defined? Do you know the panel Hz limit? How much of what we know is fact vs speculation.

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It’s called pixel persistence afaik, what I’m really interested is how much of an issue is it at all, @VoodooDE and @SweViver can’t see it, even @mixedrealityTV didn’t notice it for more than a month the he had been using the 8k so much that he didn’t mention it in his review, he only seemed to notice it later on, so it doesn’t look like much of a deal breaker if at all.

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That’s the problem we seem to be going around and around. But two testers/reviewers think it is a deal breaker and two do not. I guess you go with who you most trust but that’s not a concrete decision.

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Not correct, both the scaler and the lcd panel have its intrinsic limits… and the panels can’t do more than that, unless new tech comes along…

There were multiple past threads on this…most of you were present, and…still making these questions ? 'cmon…

Yeah I remember there being no fact just speculation from everybody due to Pimax refusing to talk about hardware specs. Unless I completely forgot which is possible :smiley:

Are you saying the panels can’t do 90Hz?

Pimax stated the panel performed at 90Hz in a different project (presumably using a SoC with MIPI output). The bottleneck could be the DP 1.2 (but only if they had to use a different mode than the 5K, e.g. other vblank) or the scaler, which doesn’t tell us how close to the limits the other parts are operating. That said, the frame rate causes a 1.4ms timing difference; that’s unlikely to be noticed on its own, but would be very clear if the motion prediction was that far off (over 11%). I’d file it under probably possible to improve with a software update but not possible to completely eliminate.

Something to test if you want to narrow the issue down: If it was related to pixel persistence or transition times, you’d see similar delays on everything that moves. In particular things would have more motion blur, probably tending towards dark or light. If it’s specifically when the head moves, not e.g. game models, hands, or eyes, then it’s more likely to be tracking related.

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'cmon…here we go again… there are a bunch of threads on that one (you was following these in the past, even replying…) , with some useful material and info, DEEP technical material to say the truth…

Do some serious research instead of wasting your time again and again just reading gaming reviews from idiotic self-appointed “geeks” and cheap , useless talk on this forum, just to kill time and impatience. :smirk:

Lillo, Please think a little before you reply so we can remain as productive as possible. Comments like that are just designed to piss people off.

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Ok, so tell me…what is productive in asking the same question again and again ? I’ll make you the example of someone not even remembering a talk did with a friend, like it was never happened ? It would scare your friend out of his socks, and probably offend him so much that he will thow your friendship away at once…

Too many people in this forum just waste time in useless, repetitive talk, quackery and kiddish rant, where they should pay attention, learn and grow up…not circling in a round and round and round way endlessly…

There’s absolutely no cure for stupidity…for some…

To be fair so is asking the same question over and over again even if it keeps being answered, but not in the way you would like it to be.

The thing is I remember Pimax mentioning that they got 8k to 85hz at some point, they probably lowered it to 80hz since it was more stable:

“We are currently conducting tests for 75Hz to 85Hz. The 82Hz is already passed the initial test, now we move on to optimize the prototype to 85Hz, and do more compatibility and stability test.”
http://community.openmr.ai/t/pimax-8k-refresh-rate-progress/3859?u=skyrimer

So if pixel persistence becomes a real problem and it’s related to refresh rate, and I mean “if”, they could try to get the screens back to that refresh rate and it should improve pixel persistence, even 82hz that seem stable should help.

And that’s another problem with this 5k vs 8k debate, that many of the issues are moving targets that could eventually get fixed. Things like refresh rate, rendering pipeline, upscaler optimization, we simply can’t say which headset will be the best in a year, there’s way too many things that could change.

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That would have been the productive way, looking for different aspects of the matter discussed…but unfortunately very few here do it that way…

To get an answer?

The “world moving with you” effect is still an unsolved problem. So yes, lets keep talking about it rather than just…not.

You never add anything constructive but love to lecture people that they should open their eyes, research, find the truth blah blah. It neither helps the discussion or provides any insight into alternative theory. The old adage “If you can’t say anything nice then don’t say anything at all” comes to mind.

Childish comment.

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I think they needed more back-lighting LEDs so I guess some power was redirected to that and so a few Hz were sacrificed?
If this is about power budgets then could that be improved? Powered breakout box for example.

i thought the pimax had a powered breakout box.

it has a powered splitter box so that you can have >5m cable extensions (I think) but not sure there is any extra power going to the HMD from that too. This might not even be the solution but if it was they could sell a new breakout box at a later date that allows the HMD to get more power if that is a solution.