Road To VR Hands-on: VRHero “5K” Plus. Pimax "8K" also commented

You cant see “more” pixels than native no but the contrast, the brightness the sharpness all travel from the panel through the lens (which can add artifacts) to your eye, and if the lens is crap then the image you get is crap.

Contrast and brightness - yes. Sharpness - sadly, NO. As long, as you can see SDE. If, for example, lenses are really bad, and you can see SDE only in the image center, not on the sides, better lenses would fix that, of course.

Fresnel lenses are less sharp than normal lenses. It is a fact. Why are you still arguing :slight_smile:

Seen SDE mean nothing, unless you have the exact measure lens deformation matrix HXW you would not able to say for certain anything. And even if the headset add only on pixel contours would be sharper with good optic.

Image resolution - Wikipedia :
For practical purposes the clarity of the image is decided by its spatial resolution, not the number of pixels in an image. In effect, spatial resolution refers to the number of independent pixel values per unit length.

It’s certain that all those variables FOV, optic, pixel count are related on the final perceive image quality but better optic always give you better clarity.

For the case at hand it’s difficult to just judge just by a fews comment on a small review

I’m not arguing about what lenses are sharper, I’m just pointing to the fact, that if you can not get sharper image, than your source image. What is on the screen - is a golden standard, nothing, NOTHING would surpass it. And if you can see technical artifacts of the screen (like SDE) already - this is it. Finita. No lenses would help yo to go beyond that.

Lens quality will improve sharpness as well. Sure optics can’t make the picture better than the source; however lower quality optics can decrease the reflected image quality in areas like sharpness contrast (creating artifacts like godrays 4 example).

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Number of pixels IS define what screen can show. If you can see pixels or even sub-pixels already, no optic would help you to see more details. Seeing SDE, means that you are there already.

Well yes, that’s obvious and nobody was debating that??. I was debating your first reply to my post.

What I’m saying is that seen SDE is to vague comment to judge. I see SDE in all my headsets but clarity is difference for all of them. SDE is also variable between panel types.

you right that we can’t have more information that the pixel count enable it. But another factor is our eyes perceive sharpness is not equal to real sharpness. So this factor can also influence a review

Than we have nothing to debate. There is no point in putting better optic if other components can not support it. Putting 5K$ optic on 300$ SLR will not do much good. And currently, biggest problem of HMD’s is not optic quality, they are not there yet. It screens resolution and computing power, to feed higher resolution on descent frame rate. Only when those things are solved, better optic would play major role. For now - it should be “good enough”, nothing more.

Which is extremely subjective.

Now under optical tricks look at avegant(sp?) Glypth? Dlp projection into the eyes at 720p no sde or visible pixels.

Or we could look at psvr which uses better quality oled (rgb instead of pentile) & a filter to eliminate for the most part sde & uses aspherical lens opposed to fresnel.

Each lens type has pros & cons. In VR we are looking for the best/low price point. HeroVR by its price point should have the best & most expensive & yet it has issues as the article lays out.

Wearability sky has an interesting hybrid fresnel lenses.

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I see were we disagree here, were taking about bad or good optic as it was something scalar. Every headset under 1500$ as optic that has lot of geometric deformation and can’t be qualify as first grade optic. so for the same pixel count you will required to deform the image more to compensate and lose resolution by the process. If you put first grade optic would will gain in image quality because the image will be closer to the LCD pixel count.

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You can always improve optics to get as close to optimum from panel to eye (in fact this is what products like Projectors do, they have the same 1080p panels but use better optics for their higher end models), cost goes up of course the more perfect you want it. And putting a 5k lens in a $300 body will make a huge difference to the quality of the photographs from its stock $99 lens, it is absurd to think it will not make much of a difference.

Edit: If we are talking percentages of what hardware will improve the Pimax 8K image then lens quality will be up there alongside panel quality and IPD adjustment.

I think we will have to agree to disagree on these matters :slight_smile:

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We disagree on what can be done with better optic. Can optic improve brightness and contrast for modern hmd’s? Most probably it can. Is there something to do better with geometric aberrations? Most definitely. But in sharpness department? I don’t think so. If you see SDE already, there are no more additional pixels that screen can show.

[quote=“D3Pixel, post:34, topic:5201, full:true”]
And putting a 5k lens in a $300 body will make a huge difference to the quality of the photographs from its stock $99 lens, it is absurd to think it will not make much of a difference.[/quote]
But it still would be a huge waste, because cheap body won;t be able to use full potential of the optic.

[quote=“D3Pixel, post:34, topic:5201, full:true”]
Edit: If we are talking percentages of what hardware will improve the Pimax 8K image then lens quality will be up there alongside panel quality and IPD adjustment[/quote]
Of course lenses are important for good image, just currently not in the sharpness department. For better sharpness we need to improve screens first.

That is a common misconception. Many pro photographers will tell you that the Lens is greater than the sensor when considering photographic equipment. In fact the sensors on many SLR cameras remain pretty much the same with small enhancements here and there on each iteration. Just google “what is more important, lens or body” and read the hundreds of people asking the question. The general consensus is that Lenses always comes first over body.

Have you ever used focus on a camera / projector? Sharpness is affected instantly. Also, If the lens is not perfect across its entire surface then focus will be off, if focus is off then sharpness is off too.

We know that the Pimax lenses exhibit issues in the v5 so they should work on that as well as trying to tweak the panels, but that’s probably simple calibration in software. They have FULL control of the optic design and need to get it nailed as much as they can before shipping. Software can be tweaked any time after it has shipped, they could even add E-Shift technology into the scaler driver to give a sharper upscaled image for instance.

You are thinking in TV/Monitor terms where a wider colour gamut mostly defines sharpness. You need to also understand what sharpness is when adding a lens in the mix…here read this article.
http://www.imatest.com/docs/sharpness/

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You are forgetting that a larger FOV requires the optics to spread the available pixels over more degrees. The Hero is only around 150, and with no upscaling, it probably has SDE comparable to the 8K but with a less blurry looking image so overall the image can look better. Lots of us have been asking pimax for a smaller FOV option exactly because of this.

No, I do not. Quoting my first postt in this thread. It get derailed later.:

[quote=“Lehmen, post:18, topic:5201, full:true”]
They are sharper not because of the optic, but due to FOV and no upscale[/quote]

Its actually reduced FoV & improved optics. Hero also has focus adjustment. Otherwise the pimax 5k would be equal more or less as there is no upscale.

However the 8k with upscaling could look just as good if not better with better optics even with the increase in FoV

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