How I calibrate my IPD setting

Today I just test Vox Machine.
In the cockpit, it will has very small text and I test to read, I have to move my face closed to it and read.

After that when I return to the main room, I found that the text “Awaiting orders…” look blurry for me.

.

And I try to check by this step.

  1. Close left eye and use right eye to read, I found that the text is sharp.
  2. Close right eye and use left eye to read, I found that the text look more blur.

So the left blur image and right sharp image make image to be little blur when look by 2 eyes.
p.s. I try to use right eye to look over the left lens too, to check that the left lens or left display is normal. And should use your left eye to look the left lens by moving headset around to check that your left eye is normal too.

And this is my solution.

  1. I close left eye and use right eye to read the “NAVIGATE” text on the monitor in the game, then I move my eye left and right (in fact you move your head) to be sure that the text is at the middle of the lenses.
  2. When text is at the center of the circle part of the lens (you can see the shape of lens around your eyes), it must be the most sharpness, after that when you turn left your head, image will be more blurry.
    But if you turn your head and look to the text, if it has more sharpness, that mean the IPD is too big, I will decrease the IPD.
  3. After you are sure that the right eye is correct, then close right eye and use left eye to do the same step. (When you swap from right eye to left eye, the text will have different position and you have to move your head for left eye again).
  4. Sometimes you have to tilt the headset too.
  5. If you set the correct IPD, when you read the text by both eyes, it must be sharp as one eye.
  6. Don’t forget to recenter your headset relate to your face too.

When I measure my IPD, it is around 66, but I always set to be 64-65. But when I use this method, I have to set the IPD at 58.9 (minimum to set).

I measure the distance between center of both lens and they are around 66-67 mm. too.

I found the issue when I use thicker face pad (vr cover 14 mm and longer distance between eyes and lens can make image has more sharpness when turn you head and still look at the target, so I swap to use 11.5 mm of pimax and test again.

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This is a really great piece of input. I am going to try this right now. I had a feeling I was running my FOV too wide. My “Oculus” IPD was about 64.5. If you had to turn down to the Pimax minimum at 66, I hope I am not SOL. I was experiencing some of that blurring on the right eye.

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I am trying this method and am a little puzzled. I close my left eye and tilt my head to frame a word in the center of the vision of my right eye, it looks sharp. Without any motion of my head, I then close my right eye and see the same letter with my left eye. The word is blurry. Shouldn’t I adjust the IPD and make the word also sharp to the left eye? Should the IPD be adjusted so that I can see the same letter clearly with either eye without any movement of the head?

When your right eye is sharp, then close right eye and move text to center of left eye by move your head and and check that it is sharp or not. If it is not sharp, try to move headset to the center of your face and test again. So your headset must be

  1. Have correct position.
  2. Have correct IPD.

sometime, may the headset is in correct position at one eye only (wrong ipd, but correct position for left or right eye / correct ipd, but wrong position.

This method to check that image is the most sharpness at center of each eye, check by one eye per time is more correct.

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When the text is in the center of my either eyes, it’s clear, no matter what the IPD is. Yet at a certain IPD I can see the same text clearly with one of my eyes closed without moving my head. So I am guessing this might be the right IPD. The IPD measurement for Pimax is confusing as it has a rather “unconventional” skewed design. It also has bigger sweet spot which can also make it difficult to decide the exact point.

I’ve also found the smallest ipd to be the closest to what I had with vive despite my ipd being 65ish

Yes the sweet spot is big and it always sharp in a lot of IPD, I only find the best IPD. But when I use 66 mm, I can see the image is more sharpness when I turn my head while still looking at the text, so I decrease value.

Oh I feel more and more puzzled. Really wish Pimax could give us more accurate built-in IPD measurement. Many of us have our IPD measured at the optometrist, but it cannot readily be used with the built-in adjustment, and it still needs our error and trial experiement. This is rather painful. @anon74848233

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The less distance between the center of each lenses is 66 while the IPD value show 59.9, I think they set this value for person who has small IPD because people still can use other part of the lenses to look. But when my eyes has IPD at 66, so I use 59.9 which my eyes can match the center of each lenses.

My eyes are 67, and I can use IPD setting from 60 to 71 without knowing which is best for me. Something in my heart is not happy with this uncertainty.

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@Sean.Huang
@Alan.sun
@Doman.Chen
This need help from you guys

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I use this app on my phone to measure the IPD of people I have over to play VR https://play.google.com/store/apps/details?id=com.vistechprojects.pupildistancemetercustom&hl=en_US
Seems to do a good job. Never get any comments about image looking blurry or distorted when I ask about it.

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Interesting discussion. I measured my IPD (so not professionally) and it looks to be around 59-60 which puts me at the narrow end of the scale. I have my rift set to lowest (59 iirc) and that is comfortable. I struggle to get the pimax image to be clear - there is a fairly constant sense of the image not being quite right - not so much blurry but more that the image for each eye feels slightly out of alignment with the other eye. I think lemming reported something that sounds similar although I haven’t found the eye fatigue he reported yet. I also see quite a lot of edge distortion - not sure if the two are related or actually just the same issue.

@anon74848233 @Sean.Huang did pimax do any testing with people with narrow IPD? Also, is it possible to reduce the IPD setting further than the dial allows (e.g. via software) or is the 59.9mm the minimum physical limit of the device?

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@anon74848233 @Sean.Huang did pimax do any testing with people with narrow IPD? Also, is it possible to reduce the IPD setting further than the dial allows (e.g. via software) or is the 59.9mm the minimum physical limit of the device?

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@anon74848233 @Sean.Huang is ignoring this question twice pimax’s idea of improved customer service?

Yes,after confirm with Tech department.The minimum IPD adjustment is 59

Thanks for the update. However when I use the IPD dial I can only get to a minimum of 59.9 - it wont go any lower than that. What can I do to get to 59 as I think that may be where I need it?

I got same value 59.9 or 59.8.

I understand that the lenses is move to the minimum already, if decrease more than this value, it will move the image rendering instead and may get some distortion.

acer can’t move lenses, but set ipd for image.

Good question! My personal measured IPD / prescriptive IPD is ≈=57.45/57.5. , horizontal offset is -10 . The cockpit instruments are pretty clear. Outside is not out of focus, rather, two of every object. Am I SOL with Pimax?

Chas

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That is interesting. Mine is +10. I wonder what causes that variance? Face shape? Mask position? (I wear my HMD a bit high, to reduce pressure on my nose, so that might be it.) Something else?