I don’t have an Og Vive. But my Vive Pro has 92 degrees horizontal FoV. So yeah, the index has roughly 20 more than that.
But it says 20 more than Vive, not Vive pro, which is 100 horizontal.
Hmm then I do think that there are simply different hardware revisions. Not sure though why that doesn’t correspond to serial number changes.
Like said, I can’t check the og Vive. But if people can see 108 degrees horizontally in ROV’s tool (the commerical version), then yes, Valve should have specifically said vive PRO
Valve were saying in interviews the fov is increased by up to an extra 15 degrees more by using the lense distance adjustment, which is an additional 15 degrees that you can’t detect in software.
Rendered fov = fov beyond whats visible in the headset (detectable in software, includes hidden area mask)
Visible fov = how far your eyes can see before the hidden areas (detectable in software)
Perceivable fov = visible fov + 15 degrees if lenses are 10mm from eyes, by bringing visible rendered pixels closer to eyes. (not detectable in software)
That 145 number is entirely on guy who wrote that article - nobody else.
I can’t count how many times I have cringed in my chair over the past years, as “influencers” have considerably more often than not been spreading utter misconceptions about several VR matters, in articles and videos, militantly propagated by brand warriors, ensconced in one trench or other.
I suspect that 145 comes from exactly the same not understanding geometry as is probably the root of Pimax’s 200° claim: They are calculating the length of a hypothenuse, instead of either of the angles at its ends, and apparently not understanding the difference.
I, unthinkingly, made the same mistake at first, before it was pointed out to me.
Nobody should ever state diagonal numbers to begin with - it is a useless number, which might have had some value with TV:s, back when there was only one aspect ratio to consider, but has zero coherence with VR. We need to know specific FOV for at least horizontal and vertical.
Despite this, I have met no lack of aggressive people demanding both that diagonal should be the one and only standard, along with the equally nebulous “megapixel” for resolution.
In case this s needed: There is no “extra” FOV to be gained by coming closer to the lenses; Only less existing FOV to be occluded by the aperture of the lens from being too far away.
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Yeah I agree with all the points you made in your above post jojon. Aspect ratio makes it important too, because diagonal fov will be different in a 1:1 aspect ratio display vs a 16:9 or 5:4 aspect ratio display.
We need to just stop using diagonal fov as a whole but marketers never will because they can use it to inflate numbers.
No. The rendered FoV is what’s being shown on the panels. But you can’t always see it all because sometimes part of the panel is just not visible. Also if you move the headset further away from your eyes, you see even less. That’s what Valve meant. But the rendered FoV, as specified by Risa’s tool, is really the max.
Well in that case then the artisan only has 130 diagonal visible fov/ 120 horizontal visible fov; and 136 diagonal rendered fov / 126 horizontal rendered fov. And Valve is lying about their specs too.
They didn’t specify a model when they said “Vive”. Is that lying? Maybe it’s not the whole truth. But at least to me it’s very different than telling people that the Artisan has 140 Fov when it actually has only 120 (at least mine)
I see no lies in Valve’s specs; Only nebuluous statements that are extremely easy to misinterpret - whether written to be so on purpose, or not.
It seems to me that most untruths people accuse manufacturers of advertising (with Pimax as a repeat offender exception), comes not from the the manufacturers and their advertising, themselves, but from the reality-detached evangelising of overenthusiatic fans.
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Its the difference between false and misleading advertising which is still bad either way you look at it.
Whilst I think Jojon is “actually” correct that decreasing lense distance to eyes may make some of the lense invisible, but it also ensures that your peripheral fov doesn’t have any black bars and your whole vision sees the 90/100 visible fov. So I think that decreasing lense distance to eyes also “technically” increases fov by “10-15 degrees” / so black bars aren’t as visible, whilst also “actually” decreasing visibility of rendered fov by 10 degrees at the same time.
No. Well it increases the visible part, sure, but not the rendered part. That always stays the same. You can’t see more than there is.
Valves been saying it has all this time thats why they advertised an increase in fov.
The truth is always in the middle. I agreed with all your posts as well as jojons, but theres merit to what I just said. If you bring lenses closer to your eyes it makes black bars less visible.
That technically increases fov whilst making some of the lense invisible
And yes I agree you cant see more pixels than whats visible on the displays through the lenses, which is the same no matter the distance of the lenses. And jojon is right making the lenses closer to eyes can in fact make all the visible pixels less visible.
But why? Because you bring the lenses closer to your eyes so that you have less unused peripheral vision on small lenses. Thats what I meant when I said fov is technically increased whilst actually decreased if lenses are brought closer to eyes.
Having said that I agree it shouldnt ever be factored into or used as part of a “fov” measurement
That Aspect ratio is not correct, if you have 16x9 the Hor vs Ver will be 16 / 9 it will not be 1:1 when its 180.
Rendered fov is the degrees including the invisible pixels beyond the hidden area mask.
Visible fov is the degrees of the visible rendered pixels in the lenses
Perceived fov is what increases when lenses are brought closer to eyes, slightly decreasing visible fov if lenses are brought so close to eyes some of the lense area becomes invisible.
Well if you definite it like that:
rendered Fov >= Visible Fov >= Perceived FoV. Though I think it makes no sense to define differently ‘visible’ and ‘perceived’. You see what you see = visible/perceived. And what you can see depends on how close your eyes are to the lenses and if there’s any fabric blocking anything.
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Yes thats what i mean by “technically” increasing fov.
However having said that technically its not increasing fov at all, as you said the rendered and visible pixels stay the same and in fact the visible fov may be reduced by increasing perceived fov by reducing lense distance to eyes.
So you really end up with like “115” degrees perceived Hfov with “90” degrees visible Hfov when doing so on a 100 degree Hfov lense
I can’t say how many times I have been in a heated argument with somebody, where it has turned out we were actually in perfect agreement all along; Only, the way each of us expressed the point came across as its opposite to other; Language can be a blasted thing. :7
It is easier, for more people, to get closer to the lenses with the Index, than with the Vive. That is all Valve claims. If anybody reads it otherwise - that’s their interpretation. :7
(I happen to be one of those who are not as much helped as others, due to deep-set eyes, and prominent brown, and low IPD, and prominent cheekbones - both in terms of depth and width. 
-I still get 10° more than I did with the Vive if I make the HMD dip in under my brow, and those are 10 fairly focussed degrees.)
I am not sure which specific black bars are being mentioned now.
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No, you are slightly incorrect there.
Visible FOV is what can be seen / what is visible within the lenses.
Perceived fov is how much FOV you actually perceive or see, within your eyes.
So if you reduce lense distance to eyes you may make some of the edge of the lenses (a.k.a. visible fov) invisible, whilst also making the lense take up more of your vision so black bars in peripheral vision are less visible.
So that makes, in vive lense with 100 horizontal degrees of visible fov for example, reduced to 90 degrees horizontal visible fov if you move the lenses really close to the eyes, but the eyes see 115 degrees or more of “perceived fov” within that 90 degrees of “visible fov”; depending on how close the lense are to your eyes.
The closer the lenses are to your eyes some of the lense becomes invisible but you have less unused peripheral vision / less black bars on the edges visible.
It also doesnt look like ski goggles as much when you increase perceived fov and reduce visible fov by reducing lense distance to eyes.
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