My Oasis has splotchier lighting than any early Paperwhite or Voyage I've seen.

[kobayashi]

Originally Posted by Atunah

Well then, here is one for you. My Voyage has no color gradient, or whatever that is called. It is even top to bottom, left to right.

My Oasis does have a gradient. So I can see it, yet there is none of my Voyage. Those are the facts.

I am keeping my Oasis as the level I am reading at, light at 10, I do not notice it most of the day. There are a couple of moments early morning, or in some dark hallway I can tell one side being what I call warmer, and the side to the buttons being cooler. But it is barely there. If I turn up the light to 12 or more, I can see it more and more. I don't need my light that high. At 14 it would really bother me. Again, too high for me to read, but someone that would notice it and needs the light that high, would maybe not be happy with it.

Although I was hoping the Oasis had a screen as even as my Voyage, everything else I love on it so I am keeping it. As I don't notice it really at light 10.

But yeah, I got lucky I guess with my Voyage. Its screen is perfect.

Only thing I noticed is that my Voyage gets a bit "dirty". What the heck is the term. Particles of previous lines of text leave a shadow behind until it refreshes again. That is something I do not have at all on my Oasis. My Oasis I counted didn't refresh til 50 page turns. . My Voyage did 12. I might be off one page or so. But that really surprised me. Oasis stays totally "clean" that way.

I'm glad that you're unable to see the screen problems on your Voyage and sorry that you can see them on your Oasis.

[Atunah]

Originally Posted by kobayashi

I'm glad that you're unable to see the screen problems on your Voyage and sorry that you can see them on your Oasis.

I suggest you re-read my post. There are no screen problems on my Voyage. I know this as I am the one that owns it, not you.
They are there on my Oasis, but not noticeable enough for me to be bothered.
Its the same eyes that look at both screens. My eyes, not yours.

You don't even make sense anymore.

[Sirtel]

Originally Posted by Atunah

Only thing I noticed is that my Voyage gets a bit "dirty". What the heck is the term. Particles of previous lines of text leave a shadow behind until it refreshes again. That is something I do not have at all on my Oasis. My Oasis I counted didn't refresh til 50 page turns. . My Voyage did 12. I might be off one page or so. But that really surprised me. Oasis stays totally "clean" that way.

Yes, my Voyage does it too. "Ghosting" is the term, I think. My Voyage has quite a bit more ghosting than either one of my basic kindles, but not enough to seriously bother me. My Oasis hasn't shipped yet, so I can't compare with it.

[HarryT]

Ghosting is something that seems to vary noticeably between individual eink panels. My Voyage has virtually no trace of it, but my PW2 has a significant amount.

[Atunah]

Yes, thank you for giving me the term. I totally forgot that. I remember the talks back when we had K1's and K3's about that.

Yes, my Voyage has it worst than say my basic with buttons. On the last couple of pages before refresh its quite visible. If I noticed. Usually I am in a book so I don't pay attention. I just noticed that my Oasis has none of that and that it goes for much longer before it refreshes. Much much longer.

[shalym]

Originally Posted by AnemicOak

Every time a new PW comes out there are the same complaints we're seeing here from what I remember.

Exactly.

Shari

[badgoodDeb]

Originally Posted by Atunah

Yes, thank you for giving me the term. I totally forgot that. I remember the talks back when we had K1's and K3's about that.

Yes, my Voyage has it worst than say my basic with buttons. On the last couple of pages before refresh its quite visible. If I noticed. Usually I am in a book so I don't pay attention. I just noticed that my Oasis has none of that and that it goes for much longer before it refreshes. Much much longer.

I wonder if the age of one's Voyage screen vs the brand-newness of all Oasis screens, makes a difference in the ghosting? Anybody know the electronic reason sufficiently to say if ghosting increases as a device ages?

[HarryT]

I don't think it's age related. It's something that's inherent in all eink displays, and some screens seem to exhibit it more than others. No modern screen has anything like the amount of ghosting that the first generation eink screens did, though. They refreshed after every page turn, and needed to do so. Pretty much any modern device can go for 10 or so redraws with minimal ghosting before a full refresh is desirable.

[kobayashi]

Originally Posted by HarryT

I don't think it's age related. It's something that's inherent in all eink displays, and some screens seem to exhibit it more than others. No modern screen has anything like the amount of ghosting that the first generation eink screens did, though. They refreshed after every page turn, and needed to do so. Pretty much any modern device can go for 10 or so redraws with minimal ghosting before a full refresh is desirable.

Correct. I set my readers to refresh every page turn for this exact reason. It may be more jarring to others who like to go as long as possible without refreshes but I prefer to have no ghosting.

[Yolina]

Originally Posted by kobayashi

I set my readers to refresh every page turn for this exact reason.

Same here

[NullNix]

Originally Posted by kobayashi

Which is what I originally guessed because only the Voyage and Oasis have the flush glass. I guessed that it was an AR coating of some kind just like you can see a rainbow effect in the AR coating on the sapphire of some watches.

Hm. The rainbow effect on sapphire is a diffraction effect (as is the varying colouration on beetle cases and the heads of mallards, as it happens). I would expect any such effect to be caused by the diffraction grating, not the glass. Glass *can* diffract, but the effect should be minimal, particularly with small thicknesses of glass as in the Kindle. (But perhaps the 'gorilla' part of gorilla glass has additives which increase diffraction? You'd think Amazon would have taken a lot of care with that, with a diffraction grating already in the mix...). If this was the case, i'd also expect you to see *strong* rainbowing when the frontlight was off and the Kindle was lit only by the Sun (which is, after all, passing through a double-thickness of the same thing before it reaches your eyes).

I'm wondering if anyone knows how monochromatic the light from the LEDs is? It can't be completely monochromatic, surely, since the diffraction grating has to send the light in divergent directions at each point, and AIUI this requires multiple wavelengths so the waveguide can split them off one by one out of the screen. I'm not sure if it's optically possible for the wavelength to be completely invariant across the screen whle retaining a waveguide, though they could probably apply yet another variable coating to absorb the varying light and re-emit it at a constant wavelength -- but this would likely also scatter the light, which would be disastrous for clarity.

Can anyone who actually understands optics answer this?

[disconnected]

Originally Posted by Cinisajoy

Please define a NORMAL LED level.

Oh wait, you can not do that.
What is a normal level to your eyes might be too bright to me and too dark to HarryT.
That is why ereaders come with adjustable lights.
There is not a normal, never has been never will be because ALL humans see differently.
So either adjust the lights where they don't bother you or get rid of the ereader and buy something else if the lights are that annoying to you.
You have made your agenda perfectly clear.

I think he's just saying that he can see the gradient at what would be his own normal reading level. I can see them on mine at my normal reading level too but luckily for me they're very faint so they don't bother me. I understand the frustration though because my Voyage has a very noticeable shift, to me, at my normal reading level. I found it incredibly distracting.

[NullNix]

Originally Posted by vampmiller

It seems some people are arguing whether it exists or not even when others have taken photos to prove it does. And it bothers me people say photos show something that isn't there. If you can photograph it, it exists. If you can't see it when you use it, that's fantastic and I am totally envious.

Say rather, if you can photograph it, it is an effect which is emphasised by a camera's CCD sensor. I am now going to go off on a massive diversion of topic because this stuff is just really cool and if I babble about it enough others might come to agree, or at least might come to see why comparing photos of e-ink screens to see what they'll look like on a real device is a complete waste of time, and getting angry about it is even more of a waste of time.

A CCD sensor is not an eye. It is also not a magical detection device of things that 'really exist'. What 'really exists' is light in motion, oh wait no, an electromagnetic field with specific values at every point in space, oh wait no, it's a state vector describing a vast quantum superposition of fields and particles (we call it 'the visible universe') atop a relativistic spacetime metric... there is no way to detect the portion of this superposition hitting a surface with complete accuracy, even in principle and with utterly perfect detectors (Heisenberg's uncertainty principle forbids, as does monogamy of entanglement). "Reality" is, to a strictly limited degree defined by quantum physics, ineffable.

Now a camera CCD detector has a bunch of bad cells in it, and only three types of sensor, which respond to only three wavelengths of light (roughly: there is variation, so the same type of sensor in distinct spots will respond to slightly different wavelengths); a visible scene is reverse-engineered from the output of this with a whole bunch of manufacturer-specific corrections to try to figure out what colours and intensities to present to the human. This is clearly not 'reality' in any sense. Camera sensors are not reality detectors. They are not-terribly-good sensors of a few specific wavelengths of light. It is very easy for them to photograph things that are not there, as anyone who's ever tried to clean up the horrible mess that is a raw photo (straight from the CCD) without software assistance will know well! Getting the colours right is more or less an exercise in guesswork to start with, and the intensity often seems to waver madly across the image until you teach your conversion software the varying intensity response of different parts of your allegedly-but-not-actually-all-that-constant CCD sensor.

Equally, the human eye has no pretensions to observing absolute truth: it's an even more terrible squidgy fault-filled optical instrument with hopeless resolution outside one tiny area, with lots of blood vessels and neurons layered on top of it (!) which has subsequently been massively optimized by evolution (some of those neurons, being translucent, do double duty as light guides, for instance!) and given a huge pile of immensely powerful dedicated neural backing to get the mental model we call a visible scene out of the resulting smeary mess, via a bunch of inverse optics which derives a 3D scene from the 2D image on the retina: this is necessarily an approximation, and as optical illusions show it can reach wrong conclusions.

Some of the work the visual cortex does involves making really quite radical adjustments to perceived colour and contrast levels: these adjustments are optimized for making sense of objects in the real world, not for observing the levels of colour and intensity across a piece of paper or e-ink screen or for observing what is "really there". For instance, one adjustment made very early in the visual cortex is to use both sharp and gradual colour and intensity changes in an apparently continuous object as a clue to the 3D shape of an object with constant colour that is partially in shadow; so a Kindle screen with a colour gradient might look to you to be a screen at constant colour that is very slightly bent: note that if this were a piece of paper that really *was* very slightly bent, the appearance might well be identical. (Again we see that what we are looking at is never reality: it is a model encoded in transient neural firing patterns, that's all. It is no more reality than what comes out of a CCD is reality.)

So these are both necessarily approximations very far removed from anything like objective truth, and they differ significantly from each other: indeed, it would be astonishing if they didn't, since we don't actually know precisely how human vision works yet, so it's a tall order to emulate it precisely in an artificial detector. A particularly radical example is their handling of intensity and contrast, but colour is quite differently handled, as well, with most CCDs being equally sensitive to each of the three colours they can detect, with a little post-facto adjustment in the camera firmware which takes it a bit closer to the very uneven frequency response of human vision, optimized as it is for the light of the sun; relatively insensitive to blue light, etc. (Again, if you've done raw work you've had to do this yourself.)

e-ink screens are optimized for the human-eye sort of terrible optical instrument, not the camera CCD sensor sort of terrible optical instrument. A mythical all-sensing being that could somehow see what was Really There would surely observe that the EM radiation emerging from an e-ink screen looked nothing like what emerges from paper at all -- but this is just as surely irrelevant. There are few mythical all-sensing beings among Amazon's customers!

(apologies to kobayashi, it looks like there's one. )

[Cinisajoy]

Originally Posted by disconnected

I think he's just saying that he can see the gradient at what would be his own normal reading level. I can see them on mine at my normal reading level too but luckily for me they're very faint so they don't bother me. I understand the frustration though because my Voyage has a very noticeable shift, to me, at my normal reading level. I found it incredibly distracting.

Alas, if you read all his posts, that is not what he said. He insulted everyone that did not agree with him.

Your phrasing is understandable.

Now since a Voyage is not a cheap device, when you realized the lights were distracting, why didn't you return it?

I cannot wrap my head around keeping a 3 figure gadget that I would not be able to use.

Now I do have to say that this thread and a couple of others are saving me a fortune.
I have decided I don't want a front lit ereader.

[disconnected]

Originally Posted by Cinisajoy

Alas, if you read all his posts, that is not what he said. He insulted everyone that did not agree with him.

Your phrasing is understandable.

Now since a Voyage is not a cheap device, when you realized the lights were distracting, why didn't you return it?

I cannot wrap my head around keeping a 3 figure gadget that I would not be able to use.

Now I do have to say that this thread and a couple of others are saving me a fortune.
I have decided I don't want a front lit ereader.

The short answer is I'm an idiot. I hate to return things so I managed to convince myself that I could get used to it. Predictably enough, I was wrong. It may not totally be the fault of the Voyage. My eyesight isn't great, I need a brighter than average screen, and I wear progressive lenses, all of which probably contributed to the illusion that the text near the top of the screen was swimming away from me.

I never managed to read comfortably on an unlit ereader; before they were lit I kept going back to reading on my phone.

I'm really pleased that my Oasis is much better for me.