If you’ve ever had eyestrain, distortion, headset placement or clarity issues with Pimax headsets and you were unsure why, or if you were contemplating buying a Pimax headset but you had those concerns then this is the thread for you, as it discusses the causes and solutions to those issues, and the physical headset placement adjustment and optical adjustment required to properly use Pimax, as well as the limitations in the current lenses and the current Pimax headset and lense design.
(Even the 8KX but to a lesser respect regarding unused pixels in the hidden area mask as the 8KX has slightly smaller panels than the 8K+ meaning a greater than 78% of rendered pixels must be shown on the 8KX.)
(Note: For an optimal headset view with minimal distortion, it’s required to have:
Correct Headset Placement
(i) a thicker or thinner face foam depending on your eye depth,
(ii) physically placing the headset further up or down your head to look through the top or bottom parts of the lenses, and
(iii) tilting the headset up to the sky or down to the ground, to accomodate for biological variances in brow, cheekbone and nose protrusions, and adding or removing to the top or bottom facial foam thickness or nose foam thickness as necessary to get a clear view,
(iv) tilting the headset to the side slightly and/or using a +/- 0.5-1 vertical or horizontal software IPD offset to correct for any facial asymmetry.
but these are not fully discussed in this thread. The focus of this thread is the extra clarity in both lenses at the same time, the extra depth perception, 3d stereo effect and binocular overlap, and eliminating eyestrain and minimising distortion that the required headset placement and optical adjustments to use Pimax headsets and the extreme IPD mod offers.)
Required Optical Adjustments
Pimax headsets, anecdotally at least, require you input your Near IPD value into the hardware IPD slider to get an optimal view with minimal distortion, which is usually 3mm less than your normal / far IPD value when looking at objects at a distance (because our eyes converge and get closer when looking at objects closer to our noses)
Some people can’t input their near ipd value into the hardware IPD slider, who have a 60mm measured far IPD value and a 57mm near IPD value – and thats where the extreme IPD mod is useful (it gives an extra minimum 4mm IPD value making the minimum 56mm instead of 60mm). The software IPD offset is not sufficient to correct issues with the lenses as the software IPD offset does not cause the placement of the lenses to change, only the hardware IPD slider does this (and the Extreme IPD mod to increase the range of minimim hardware IPD down to 55mm from 60mm)
Both images appearing clear in both eyes at the same time is not an issue with the headset design or biology so much, although lense depth or face foam thickness variations being required due to varying eye depth of each user affecting the perception of distortion is due to biology and the lense design.
The issue of both images not being clear in both eyes at the same time has to do with the lense design, which is why it needs to be reduced 3mm less than your measured “Far” IPD value to your crosseyed “Near” IPD value, because the lenses need to be closer together than the value Pimax claims represents your IPD in order for images to be clear in both eyes at the same time.
This compromises clarity to the sides, although you can get a balance of clear straight view and side view by reducing your IPD in Pimax using the hardware IPD dial by a few mm less than your measured IPD, you will lose the ability to look clearly at the sides in doing so due to the lense design.
Summary of issues
The current lense design in Pimax headsets and recommended headset and lense placement suggested by Pimax, allows for a clear view in one eye at a time on each display when looking left or right (when looking left its clear in the left eye and blurry in the right) and vice versa on the right eye when looking right its blurry in the left eye, and always blurry in both lenses when looking ahead with both eyes.
The Pimax lense placement model only allows for clarity in one eye at a time when looking to the sides and not straight ahead. If you measure the distance between the centre of each lense you’ll find its 70mm when the hardware IPD slider says 60mm, showing you that Pimax doesn’t intend for you to look through the centre of the middle of each lense).
To correct this, it has been recommended by enthusiasts to input your near IPD value, or up to 3mm to 5mm less than your regular measured IPD value, into your Pimax headset’s hardware IPD adjustment, to move the lenses closer together to achieve the clearest view with minimal distortion, when all other headsets use the normally measured and normally used far IPD value for looking at distant objects.
The enthusiasts’ suggested optimal headset and optical placement arrangement allows for clarity in both eyes staring ahead, and some clarity to the sides, whilst the more clearer you allow the lenses to be ahead of you the less clear the side vision becomes.
Reducing the hardware IPD 10mm less than what the headset shows when adjusting the hardware IPD knob allows you to look through the centre of both lenses clearly at the same time but not the sides.
Reducing the hardware IPD in your Pimax headset to 3mm-5mm less than your measured IPD value allows for a clear view straight ahead and to the sides at the same time on the current lense design.
The software IPD offset is not sufficient to correct issues with the lenses as the software IPD offset does not cause the placement of the lenses to change, only the hardware IPD slider does this (and the Extreme IPD mod to increase the range of minimim hardware IPD down to 55mm from 60mm)
For people in the below 63mm IPD range (62mm and below range), the extreme IPD mod may be required to correct the optical issues and achieve clarity in both lenses at the same time using the current Pimax lenses, and to minimise distortion and eliminate eyestrain. Extreme IPD mod: /r/Pimax/comments/bq4q8f/extreme_ipd_mod
Pimax and even enthusiasts have historically attempted to attribute the cause of design flaws in their headsets and optical issues related to the lense placement or recommended lense viewing position in their headsets to biological variances and incorrect headset placement, which I’ve addressed and ruled out above and are more attributed to distortion rather than clarity issues in both eyes which are due to incorrect lense placement, due to a lack of sufficient information to understand the cause of the underlying problems and the differences between headset placement issues and optical adjustment related issues.
As a result, many Pimax consumers have incorrectly been advised to use a software IPD correction to fix a lense placement related clarity issue inducing eyestrain, and as a result of that bad advice and a lack of Pimax instructing how to correctly set the heasset placement and optical adjustments required to view Pimax headsets correctly, they have sold their headsets due to believing that Pimax headsets are just wrongly designed or that their face is just the wrong shape to use the headset.
Some users have experienced product issues due to manufacturing flaws in the past, rather than issues or flaws in design, such as incorrectly placed panels at incorrect angles which required differing software IPD offset adjustment for each eye, dead pixels on panels and Mura similar to HP Reverb Gen 1, and other issues such as fragile housing. These have seemingly resolved for the most part as Pimax improved the quality of their headset housings and as they changed to automated manufacturing and calibration processes during headset manufacturing.
Software issues should not be an issue in the future and GPU performance has improved significantly with Pitool stable version .262, however the Pimax Experience releasing in August will offer automatic game settings, automatic hotswapping between settings and saved settings profiles for each game as well as additional back light and color adjustment options, so lack of plug and play, difficulty of use and long setup times should all be resolved in August 2020.
Pimax not changing their headset design, or distance to the screens from the lenses, after opting to use inferior lenses which introduced greater magnification and which are lenses which have a smaller sweet spot than the previous prototype p3 lenses is likely the result of the IPD discrepancy shown on screen and why “XY”mm hardware IPD on screen doesn’t usually work for people with “XY”mm Far IPD without causing blur in both eyes, as I believe Pimax neglected to change their pitool software IPD value to account for the change in lenses and reflect a new optimal lense positioning considering the extra magnification caused by the newer lenses. /r/Pimax/comments/gskg9d/pimax_deciding_to_use_cheaper_lenses_introduced/ (the threads cited in this thread are all deleted (likely because Pimax doesn’t want you to know), but here’s a backup of the proof in a screenshot gallery https://imgur.com/a/8hf8Lcl)
The consumer lenses cause a larger amount of rendered invisible pixels in the hidden area mask because the consumer lenses magnify more than the prototype lenses and the headset design or distance from lenses to displays was not changed to account for this additional magnification caused by the consumer lenses, and introduced distortion which were not visible in the prototype lenses. (Refer to the last two screenshots in the above imgur screenshot gallery link, which are from the now deleted 8K progress thread from February 2018. https://community.openmr.ai/t/pimax-8k-progress-updated-feb-6-2018/5124)
Previously visible rendered pixels, visible on the older prototype original 8k lenses, are invisible on the current lenses due to the additional magnification the newer pimax “mass produced consumer version lenses” which only show 78% of the pixels rendered on each display (thats 23% of wasted unused and invisible screen area per display which also reduces visible PPD, almost 1/4 of wasted performance without hidden area mask on), without changing the headset design or lense to display distance to accomodate for the extra magnification caused by using the newer lenses as a result of this change. (Refer to this deleted thread)
I hope this thread gives some people a better understanding of the causes of Pimax’s headset problems, as well as solutions which might make users confident in purchasing their products and knowing how to use them.