Pimax 5k+ teardown + panel info

I don’t follow you. How much is the binocular overlap according to you for the pimax? And why does this even matter in terms of sharpness?

Btw, hope Sj does not consider this discussion as hijacking. Think it may be tied to his findings, may be wrong though.

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Also this doesn’t make sense to me. your whole picture is ‘black’ so I’m not sure what you’re saying. Also I don’t understand your 1700 pixel number

How much is the overlap for Pimax is in the post I linked above.

It matters when you start to factor the full FOV angle (ie the stereo view of both eyes) by the number of pixels in this FOV and want to figure out this number of pixels.

Imagine having two panels with horizontal resolution X with zero overlap and the horizontal FOV angle A. This would have (in an extremely simplified formula) PPD of 2*X/A.

Now imagine the same FOV, the same panels, but in a full overlap. The PPD of such setup will be X/A.

Anyway I’ve done some new experiment and have changed my opinion. The lens actually shows quite a bit more than 50%. So what I did yesterday is pop out the lens, look through it at a newspaper, move it till bit becomes in focus and then mark the left and right edge you can see on the newspaper and measure that. However that’s not correct. The thing is that you can not read beyond that 50%, because your eyes cant turn that far outside. However you can see beyond that with your perhipheral vision. I did the same experiment again, however now moving a coin with my finger into/out of the area. I could see movement in an area of about 9.5-10 cm. So that’s much better than my previous number. In fact that should equal to about 75-80% of the panel. So my previous measurements weren’t correct.

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So you’re saying the pimax has 87 degrees overlap? To compare fairly maybe we should only compare the binocular overlap then.

Anyway as I said in my last post, the panel utilization is nowhere as bad I though it was.

EDIT yeah my final measurement is that I can see movement in 9.7 cm horizontally, so thats 79%. Multiplied with 98% vertically I’d say i can see roughly 77% of the panel through the lens.
EDIT2 well it’s actually a bit less since the lens of course isn’t a square, so you’d also have to subtract the edge areas that you can’t see. However that’s the same thing with the Vive Pro of course

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The minimum software IPD of 59.9mm equating to a minimim physical measured distance of 70mm between the middle of the sweet spots of each lenses, either has something to do with cantered displays and lenses, or Near vs Far IPD measurements, if it’s not just a discrepency between the minimal IPD software and hardware measurements.
I’m not sure how 70mm equates to 60mm, but according to Pimax it does. As far as I know if you take a curved line and straighten it, it becomes longer. And the minimal physical distance between the middle rings of both lenses is 70mm, i don’t think the fact the displays are cantered can reduce that in any way.

@anon33864247 @risa2000 would either of you like to say your opinions on the matter if the cantering of displays would reduce or increase the measured physical minimim 70mm IPD of the headsets?

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@anon33864247 Would this imply that they could use smaller panels (or squatter, since you wouldn’t want to lose the vertical height) at the same resolution to increase pixel density?

Well the ideal panel for these lenses would have been about the same height, but then about 10 cm long in stead of 12.3. However in that case they’d also need to move the panels when changing IPD of course. But yeah that would result in a bit sharper image.

Sounds about right , also the vive pro has 110 fov
Pimax 5k+ and vive pro with gear lens look very similar as far as sde goes , 5k+ wins hands down for wide fov scenic stuff but the pro gear has the better panels for colour/contrast required in fps type games , I would use the 5k+ over the standard vive pro with original lens though in fps games

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Very interesting, never really considered it like that

Additionally I think the people who report having no difficulties at similar or the same IPD measurements as those who do (Between 60-65mm) may not actually looking at the middle of the sweet spots of both lenses, if the cause is not due to biological variances in facial structure.

In fact I never noticed but indeed, in the lenses there’s a very small inner circle. That’s what the sweet spot for undistorted image will be. If your irises aren’t exactly aligned with that sweet spot then I assume that distortion will happen. That’s of course why the vertical placement on your face of the HMD matters so much too. Depending on your face shape this might not be that comfortable (in my case I need to move the HMD to a point that isnt comfortable)

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So you haven’t been looking through the middle of the smallest fresnel rings of both lenses until now? You’re probably not the first too.

It also brings another question, does the middle ring even align with an IPD graphic crosshair when attempting to converge both images? I’m guessing not since the screens don’t move.

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Well initially I didn’t. I just put on the HMD so that it felt comfortable and that I could see clearly. However that’s the “problem”. The part where you can see clearly (what traditionally is called the sweet spot) is much bigger than the distortion “sweet spot”. So I found out I had to move the HMD up a lot on my face for distortion to get better. However I could only improve it, never really solve it, I always saw distortion

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sjefdeklerk
can you approximately measure the distance between the lens to the panel please , I might try some different lens just out of curiosity

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Well I actually just put everything together and the HMD works like it did before. Which BTW means that everything seems normal in the Pimax landscape but as soon as I start SteamVR everything is totally messed up. Which makes me think that it’s a Steam problem but I really tried everything, including deleting everything, opting out of beta, re-installing older versions etc etc etc… So not sure what’s going on.

However it seems that I didnt damage anything when disassembling. it’s actually really not that hard, you just need a steady hand and some patience. The flat-ribbon cables are actually really easy to disconnect and connect again, if you understand that you need to flip up the black part, as I explained before

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was it the wide ribbon in the middle that was slightly pulled out , looks off in the photo’s

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Yeah I figured that one might have been the problem. But everything works like it did before. Not sure what’s going on, if the pimax environment works with tracking, then why doesn’t it in steamvr … weird stuff

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Is steamvr in safe mode ? or swap usb’s about
try some oculus stuff , that doesn’t require steamvr

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