IPD settings and lens position on Pimax headset

My ipd is 61. I use the software ipd adjustments for fine tuning and it works well enough for me. The thickness of the facepad is crucial, as well. It seems that the smaller the ipd, the farther away from the lenses you need to be to be able to focus. Of course, I’ve also got graduated bifocals so seeing anything worth a dam is problematic. Most of the time, I couldn’t tell you if my glasses were off or the headset lenses! Once you go bifocals, you start learning to compromise: at least I can see. Most of the time.

Who ever heard of a manufacturer providing a vertical ipd?!! One of the reasons why some get so mad at Pimax is that they have done such an outstanding job on most of this, but they just keep dropping the ball in a few areas!

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I have a 62.3 IPD. I have to have my headgear set tight so that it does not point up or down a little.
if I do not fit it just right it is still better than my Rift S. Heavey then My S but still love it.

Ya, ‘workable’ isn’t good enough. My IPD is 60. With physical ipd at minimum and using as much software correction as possible, I can’t even get close to having both eyes in the sweet spot of the lenses. I NEVER have a perfectly clear image in the 8kx. One eys is ALWAYS blurry. They screwed up, and hugely. Their response to it is so telling as to the type of company this is.

Then why don’t you and some other folks start a kickstarter with someone who has the skills to do the extreme IPD hardware mod? If it’s not worth a few hundred dollars per person, times a few dozen to start with, it’s not a good business case for a company that is already scrambling to produce more of the headsets they already have designs and tooling for.

Anyway, this topic was about @SweViver and @arminelec . FWIW, although of course their being busy is totally understandable, I too hope they know we like hearing from them. :wink:

Why start a KS when you bought a product that was/is currently being advertised as supporting an IPD range between 55-75?

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To be frank, I have an IPD of 64 and even I don’t manage to get both eyes focus on the same spot in a virtual scene (even if further away to lessen the amount of congestion applied by your eyes when believing they need to focus on something).

Looking at the hardware of the 8KX, you will notice that if you dial the hardware IPD setting as narrow as possible (approx. 60), the center of the concentric rings on each lens is approx. 67 mm apart - that is the true minimum hardware IPD, I would say. Which means that with a lower IPD than 67 at least one eye will always see a slightly blurry picture, and when you move the eyes horizontally from say left to center to right, without moving the head, you will notice that at first one eye sees a sharp image, the other doesn’t, then in the absolute center there is a small portion where both have blurry images, then the other eye turns sharp while the first one remains blurry.

In other words, the two circles of absolute sharpness (inner sweetspot) of the two lenses have no overlap at all. Simple physics (mathematics), if you ask me.

Pimax can argue that it might be 65 or 66, because the eyes do not look straight forward in absolute parallel lines, that’s true, not even when focussing at more distant objects, but it still is not anywhere near 60, and from my experience I would rule out 64 too.

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I don’t think that you’re supposed to have the eyes centered in the center of the lenses. Because the screen is angled and your eyes are (more or less) perpendicular to your face, the straight-ahead area will always be a little fuzzy, because the screen distance varies, depending on which part of the screen you are looking at.

What I think Pimax has done is to place the center of the lenses such that they maximize the area which is in focus, rather than the innermost portion of your view. I think this misunderstanding is at the root of a lot of the “out of focus” complaints.

My IPD (as measured by my ophthalmologist) is 62 mm (far) and 58 (near). Personally, I don’t have a problem with the Pimax lenses and they aren’t even set to the minimum IPD and the software IPD Offset is set to 0,0; I have the IPD set to 61 and it seems fine to me.

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indeed its usable approach to make clarity spot bigger and cover big fov but still its not ideal, i think lenses on 8kx usable, i have 68.5 but my eyes also see not equally, they do on min ipd but i preffer 66 , so sweetspot and clarity spots are both bigger.

But we have admit that this approach isnt ideal and generates some eye/cognitive fatigue, not much though but on both eyes focus overlapped hmds the experience feels different

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So in other words, it isn’t the position of the “sweet spot” that is the problem, but the fact that the sharp area at the centre of the fresnel lenses is too small?

Respectfully, I’m not sure that’s the problem. I don’t think there’s a simple solution. This is particularly true of the Pimax design, since the focal plane of the screens is angled with respect to the eyes. The issue is that designing lenses is hard and involves numerous tradeoffs. There are good reasons behind the fact that most VR headsets use Fresnel lenses, even though many people dislike those lenses.

I’m no expert, but I think that fixing the “fuzzy area” directly in front would require some sort of compound lens, probably made of multiple lenses made of different materials. The difficulties of lens design are are why professional camera lenses are big, heavy, and expensive. All 3 of those factors rule out some solutions for use in consumer-level VR gear.

I’m not bothered by some slight fuzziness. I’ve worn glasses for years. I wear multi-focal “progressive bifocal” glasses. I’m used to a certain amount of visual imprecision. I rarely even notice it. Perhaps that’s why I’m not bothered by (personally) imperceptible distortions that others find intolerable. That’s not to say that there aren’t visual artifacts which bother me a lot, such as jagged, crawling polygon edges, due to aliasing.

We’re each different and issues which are major problems to some, may be extremely minor to others.

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The XR Unit was lens modded and improve eye strain. I think the problem was that the lenses needed to have the ability to get closer that what the hardware design is able to do.

I think somebody made a tread here last year if I remember correctly

Interesting thought. Could be their logic. Although that would seem to imply that you would have to adapt a kind of cross-eyed look in general when using their headsets, the left eye looking slightly more to the left and the right slightly more to the right respectively.

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I suspect this has to do with the way the panels are constructed. (Stripe alignment, polarizing filter, etc.)
Maybe they should have turned the right display 180 degrees when installing it. With the old Pentile and 1440 the small difference was not noticeable.

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Good point, but I don’t think so. I think you’d look ahead as normal, but the area in front of your eyes is simply angled away from your view, as you look more towards the center.

By making none of it in focus to both eyes at once? Doubt it. They screwed up, and invented post hoc rationalizations to try and explain it away.

Yup. This is straight up false advertising. If I’d known this, I never would have bought one. Next time I’ll just use amazon, so I always have the ability to return. This company has lost my trust.

Live and learn I guess.

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