Eye Test!

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Nigel H-J
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Eye Test!

Post by Nigel H-J »

Today I went to Specsavers for an eye test as it has been quite some time since my last appointment my eyes are still in good shape although do need new glasses but not much difference TBH from my current set of glasses.

My question is when I asked for my IPD as am using the Quest 2 and having on pair of frames to fit inside the headset, I was told that my IPD is 31.5 Now that is a bit confusing as I googled IPD for the Quest and this is what it states:

61 mm to 66 mm: 2 (middle, 63mm)
66mm or larger: 3 (widest, 68mm)
61 mm or smaller: 1 (narrowest, 58 mm)

So what is the measurement I have been given by the optometrist? Also would appreciate some help or advice as to wearing glasses in VR. As my current glasses do not fit inside the headset I have been using VR without glasses and have been able to manage fairly well so just wondering what difference I may find when using glasses! :dunno: as my eyes are not far off from the lenses themselves do glasses improve vision? I have noticed that when flying a glass cockpit for example that the airspeed indicator I have to lean forward slightly to see what the reading is and also sometimes have to lean forward or use the zoom feature to read some of the switches but overall, especially when driving around race tracks I have been able to get the sweet spot perfectly and read text OK.

Regards
Nigel.
I used to be an optimist but with age I am now a grumpy old pessimist.

Vc Ten
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Re: Eye Test!

Post by Vc Ten »

Hi Nigel. Those figures say to me that Specsavers are giving you 1/2 the IPD ie, centre of nose to one pupil works out at 63 mm then.
I've thought long and hard for the headset route. Not specifically fot the sim, but for the drone. The dji ones are around £400, but with fairly poor eyesight, I don't know if I will have sharp enough vision to justify the cost. I wear varifocal glasses, as I need correction for distance and close work The varifocals would be a waste of time, as the focus would alter, depending where your eyes were pointing. Although the screens in the headset are only a couple of centimeters from you eyes the optics are setup so the effective focal length is usually around 1 to 1.5 meters This effective focal length varies with the headset manufacturers. So you need the prescription for your best vision at that distance, to suit your goggles focal length. You can just get a pair made up for that or use it to get the correct inserts for the headset.
Dale
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Re: Eye Test!

Post by Dev One »

I've always thought ones IPD was in the order of 120 mm & if you look at the side bars the frames have a width quoted somewhere, mine are 140 mm.
I've just had a test & new specs from Vision express & I ordered, 1 pair varifocal, one single vision reading & one blue tinted focused at arms length (about 20"). Choosing a frame for everyday varifocal I was then measured & went through the eye centring procedure. I decided not to have some of the fancier reflected index materials, but to stay with the bog standard as my last french pair where I did have a middling index did not seem to give me any advantage, in fact one could see striations in some parts of the lens where the blending between layers (for want of a better word) was not smoothed out.
We got to a point where the data was being input to the computer when it threw up saying that they could not make my Left lens for that frame design as the blank was not big enough! Thats because my nose is bent & the bridge of the specs is therefore out of position. So chose another pair which does work! Thats a first time problem, never had it before & I think a rarity for the girl doing the job.
These lenses are good & I dont have the problem of eye position relative to lens centring & looking through the striated part of the lens & hence change of focus.
Now this might be where on-line specs makers are at a disadvantage because they don't measure ones personal eye position relative to the lens centre, they use an average standard.
Sorry bit long winded - not sure it helps your problems wrt VR, but it raises a thought when you are reading airspeed for example, which programme are you using FS9, FSX, PD etc, because one is aware of the different viewpoint & vision angle scan in virtual cockpit view between them. (Hope that makes sense!)
Keith

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Re: Eye Test!

Post by Vc Ten »

Just measured my interpupillary distance. It's around 65 mm, give or take a mil or 2.
I find it very critical that the opticians get this distance correct, else I get double vision.
Usually I go to Boots, and after quite a comprehensive exam they measure the IPD with " look straight ahead" and a blob with an sharpie on one lens followed by a repeat performance for the other, then measure the distance in between. On several occasions this measuring method has failed, and I have had to go back to Boots to get them to replace the lenses (At their cost) I've commented don't you have anything more accurate? " Oh yes but we don't usually bother with it"!
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Nigel H-J
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Re: Eye Test!

Post by Nigel H-J »

very many thanks for all your replies, when I was at Spec Savers and I had omitted the following by sheer accident, on speaking to the the gentleman who examined my eyes I had mentioned to him that I use virtual reality and needed glasses to use in it.

He has given me 2 types of glasses one being to read the text from the computer and/or book at arms length and the 2nd pair for virtual reality whereby he has given me the best setting in the lenses of the glasses that I would hope to get in VR, the frames are much smaller so as to be able to wear them inside the headset without too much discomfort or risk of scratching the lens themselves.

My confusion on this is that of the IPD that one of the assistants gave me when I asked. I just hope that my IPD is within the specified range for the Quest 2 but even if it is not, after having used it since March of this year without glasses, I am hoping for some improvement and hopefully better visuals.
We got to a point where the data was being input to the computer when it threw up saying that they could not make my Left lens for that frame design as the blank was not big enough! Thats because my nose is bent & the bridge of the specs is therefore out of position. So chose another pair which does work! Thats a first time problem, never had it before & I think a rarity for the girl doing the job
This is another problem I have Keith, I broke my nose fifty years ago and my specs become out of alignment after I have been wearing them for a while, I have learnt through trial and error that if I just gently place them below the bridge, this tends to keep them in place without damaging one side of the arm which in turn distorts the frame when wearing them. I am presently using X-Plane 11 and with the amount of money I have invested in it am reluctant to go to another sim, had thought about MS2020 but with X-Plane now showing improvements to come for the near future I will stay with it a bit longer.
Hi Nigel. Those figures say to me that Specsavers are giving you 1/2 the IPD ie, centre of nose to one pupil works out at 63 mm then.
Although the screens in the headset are only a couple of centimeters from you eyes the optics are setup so the effective focal length is usually around 1 to 1.5 meters This effective focal length varies with the headset manufacturers. So you need the prescription for your best vision at that distance, to suit your goggles focal length. You can just get a pair made up for that or use it to get the correct inserts for the headset.
Hi Dale, very many thanks for replying, now I can set my Oculus for that range as have been using the biggest setting. I think this is basically what he has done for me, one pair for reading and the other one to give me the best result for VR and you have explained that really well. :thumbsup:

What had confused me was the IPD figure that I was given, but all your replies have given me a great deal of help. Will let you all know once I get them how I am managing, am due to collect a week on Friday but babs has told me that it may take a few days for me to get used to earing them in the headset!!

Again, many thanks

Regards
Nigel.
I used to be an optimist but with age I am now a grumpy old pessimist.

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Nigel H-J
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Re: Eye Test!

Post by Nigel H-J »

Usually I go to Boots, and after quite a comprehensive exam they measure the IPD with " look straight ahead" and a blob with an sharpie on one lens followed by a repeat performance for the other, then measure the distance in between. On several occasions this measuring method has failed, and I have had to go back to Boots to get them to replace the lenses (At their cost) I've commented don't you have anything more accurate? " Oh yes but we don't
Hi Dale

I did have quite a comprehensive examination which included a full scan of the eye, all appeared to go extremely well but on asking for my IPD the assistant gave me the figure quoted in my first post, not sure when they actually measured it!! :dunno: Must have been during the preliminary examination.

Regards
Nigel.
I used to be an optimist but with age I am now a grumpy old pessimist.

Dev One
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Re: Eye Test!

Post by Dev One »

The french & Vision express used after a prompt from me, a box like item that had a red & a green light which one focuses on - this measures your IPD, but it is also important to look horizontally into this device because I have have found that when driving the vertical position of the long range vision is usually out & one needs to angle ones head in the vertical plane (Zenith?) if its not correct - trouble is I forget to do this every time & the operator/sales person doesnt know or forgets this trick! Afterwards they then chinagraph the info onto the dummy lenses & check visually alignment with your pupil. If they get it right then ones near vision places the reading part of the lens correctly allowing for the angle ones eyes are at reading distance. This is for the varifocal lens of course.
Interesting yeah? Have you thought where you focus when looking in a mirror?
Keith

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Nigel H-J
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Re: Eye Test!

Post by Nigel H-J »

The french & Vision express used after a prompt from me, a box like item that had a red & a green light which one focuses on - this measures your IPD, but it is also important to look horizontally into this device because I have have found that when driving the vertical position of the long range vision is usually out & one needs to angle ones head in the vertical plane (Zenith?) if its not correct - trouble is I forget to do this every time & the operator/sales person doesnt know or forgets this trick! Afterwards they then chinagraph the info onto the dummy lenses & check visually alignment with your pupil. If they get it right then ones near vision places the reading part of the lens correctly allowing for the angle ones eyes are at reading distance. This is for the varifocal lens of course.
Interesting yeah? Have you thought where you focus when looking in a mirror?
Keith
The only time I ever look in the mirror is when having me morning shave, no good using it to brush/comb my hair as have very little now. 8)

Amazing though how far an eye test has gone from just reading a board on the other side of the room with letters on it. One thing that I have just realised is that they do not check for colour blindness why would that be? I know I am all right as had to go through the test before taking up employment as a C.C.T.V. Operator.

Regards
Nigel.
I used to be an optimist but with age I am now a grumpy old pessimist.

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