Kobo has color e-readers coming out in April

[Timboli]

Just read this very interesting article on the Blog at Kobo, which covers some of the stuff mentioned in this thread, including color e-ink readers.

eReader vs. Tablet: which screen should you be reading on?

The problem it seems to me with folk that have the view leebase does, is that they are purely going by their personal experience, which doesn't really cover long term effects or the various things that are happening that aren't all that obvious, but happening never-the-less.

The science seems quite clear to me, that an e-ink reader is better for the eyes of everyone, even if that is not visibly obvious to a user. And I say that as someone who quite happily uses a 10" Samsung tablet for ebooks that require such.

And as I said earlier, the mind boggles that Kobo brought out standard size color e-ink readers, where you truly only get a minimal benefit of color. Why the hell didn't they, brink out the 10.3" Kobo Elipsa in a color version, where the benefit of color on that device would be so much more and a really good selling point.

[John F]

Timboli, did you read the paper linked to in the article? The article says emissive devices are harmful, but the linked paper synopsis doesn't mention emissive devices, just devices in general. I didn't downlkad the paper due to it requiring personal info.

Thanks.

[Quoth]

LED frontlit Colour ereader no different emission to LCD or OLED tablet/phone with a good display adjusted properly.
Biggest cause of headaches with displays for 40 years plus is reflections from a shiny surface. The eyes unconsciously change focus from close text to far off reflection. Scientifically proven.

So mono eink with a matt screen/surface and ambient light is best.·

[j.p.s]

Originally Posted by Quoth

Biggest cause of headaches with displays for 40 years plus is reflections from a shiny surface. The eyes unconsciously change focus from close text to far off reflection. Scientifically proven.

Well, if you're going back 40 years and more, there's flyback transformer whine, crude low resolution fonts, huge gaps between scan lines, and gaps between pixels. The first one was particularly bad (beyond headaches) for some pregnant users.

[Timboli]

Originally Posted by John F

Timboli, did you read the paper linked to in the article? The article says emissive devices are harmful, but the linked paper synopsis doesn't mention emissive devices, just devices in general. I didn't downlkad the paper due to it requiring personal info.

Thanks.

No I didn't, as all the significant detail was in the article, going by what I read.

I took it as most would, that the article was a concise summary of any linked papers. So to go further for me, would be kind of unnecessary as I am not a scientist, and so any further interpretation by me, could be flawed due to personal bias on my part.

So in essence I leave it up to the experts ... or those more expert than me.

[Quoth]

Originally Posted by j.p.s

Well, if you're going back 40 years and more, there's flyback transformer whine, crude low resolution fonts, huge gaps between scan lines, and gaps between pixels. The first one was particularly bad (beyond headaches) for some pregnant users.

Transformer whine was approx 10 kHz on 405 TV and about 15 kHz on 525 or 625.
Progressive VGA and higher was a minimum of about 31 kHz, which no-one can hear.

The poor screen resolution (IBM Mono and old terminal monitors) was poor aesthetics rather than headache inducing. By 1980 (before IBM PC came out) one conclusion was reflections and the other less supported by science was to use green or brown phosphor instead of white (as used on TVs). We made monitors for Apple II, Acorn/BBC and Research Machine 380z, mostly mono with brown or green CRTs, but some colour sets, all based on Thorn 625 line TV chassis. The coloured phosphor was for market demand and gave us the edge of those selling white phosphor Hitachi security monitors. The mono screens were not matt but less shiney than the mono TV CRTs, or the later official IBM CGA (whine) and EGA (no whine).
Though 15.625 kHz, our monitors had no transformer whine in 1980-1983. The whine would have been older terminals. The 405 TV in all of UK from 1935 to 1985 with 1939-1946 gap (and parts of Ireland 1962-1985) was bad for line frequency whine of 10.125 kHz (mostly from scan coils but paritially the LOPT).

The ACT Sirius 1 (Victor 9000) was in UK before IBM PC in 1981 and had a true matt screen due to a mesh on the front. Later there were similar meshes sold to clip on. I have one in the attic from a 1980s terminal. By mid 1980s there were some screens with matt surface to the glass or faceplate as the mesh system was no use for higher resolution displays.

[Quoth]

Originally Posted by Timboli

Just read this very interesting article on the Blog at Kobo, which covers some of the stuff mentioned in this thread, including color e-ink readers.

eReader vs. Tablet: which screen should you be reading on?

It's marketing and misleading. Essentially rubbish.

[John F]

Originally Posted by Timboli

No I didn't, as all the significant detail was in the article, going by what I read.

I took it as most would, that the article was a concise summary of any linked papers. So to go further for me, would be kind of unnecessary as I am not a scientist, and so any further interpretation by me, could be flawed due to personal bias on my part.

So in essence I leave it up to the experts ... or those more expert than me.

I guess I have my doubts then, as there seems to be a discrepancy/"interpretation" between the article and the linked study?

[John F]

Originally Posted by Quoth

LED frontlit Colour ereader no different emission to LCD or OLED tablet/phone with a good display adjusted properly.
Biggest cause of headaches with displays for 40 years plus is reflections from a shiny surface. The eyes unconsciously change focus from close text to far off reflection. Scientifically proven.

So mono eink with a matt screen/surface and ambient light is best.·

Why? Why is mono eink screen (ambient or front lit) better then color LCD/OLED screen (let's assume like for like: 300 dpi, matte screen, ..., )?

[Quoth]

Only ambient lit mono ink (with usual matt surface) is better, because you never need to adjust brightness or colour temperature to match surroundings. The colour eink will need LED front light indoors.

Automatic brightness (and rarer auto-colour temperature) only seems to be much use outdoors.

A front lit colour eink is just as emissive indoors as a properly adjusted OLED or backlight LCD, which can have a very matt screen. My matt OLED and matt LCD screens are more matt (less reflection / glare) than any of my eink. One eink I gave away just on Monday has actually a glossy film that can't be removed. It's better than most small phones, but far worse than a Nxtpaper 40 (the regular model, not the 4G).

The article is full of advertising copy that's inaccurate and doesn't match the paper. A heavy reader will not get more than a week on any eink. Some phones and tablets are as good now for reading (on charge) as some eink and better than Oasis or Sage.
The eink is at a disadvantage for audiobooks etc, as the CPU can't sleep and the phone screen blanks. Also Kindle will really only work for Audible and Kobo only for Kobo. A phone can give longer running time, some new ones still have 3.5mm jack (best run time and quality), any audio book source or music, or any streaming audio (lower power on WiFi, but mobile possible).

So article mentioning of audio books and BT is irrelevant and so is colour (because it needs front light and is poorer by far than any matt OLED/LCD). Only mono eink for reflowable novels in ambient light has an advantage over a good screen (not retina, but matt) and high capacity battery phone/tablet.

I've plenty to compare and don't need to buy a colour eink to understand how inherently inferior it is to current mono ink or decent LCD/OLED with matt screen (more than one brand and possible for decades, just costs more).

The matt top layer on eink isn't anything inherent to the eink Viziplex / Pearl / Carta technology, but a decision to improve quality that adds more to cost than shiny screen, possible long before OLED on any kind of LCD and some have been nearly matt. Shiny is a fashion / marketing decision that saves on cost.

[Quoth]

So no matter how good matt OLED / LCD gets, it can only equal front lit eink, never be quite as good as ambient lit mono eink, which really is like dull slightly grey paper. You can adjust a matt screen OLED or LCD to almost perfectly match a piece of paper or ambient mono eink screen indoors, but as soon as you move, or switch between room and table lamp, etc, the OLED / LCD will look dimmer or brighter, bluer (cooler) or pinker (more rose) and unless auto sensors averaged the page, auto doesn't work. Auto can make it much brighter or dimmer with a small tilt. It only seems to work outside going between sunlit, shadow, overcase. That's what I'd excpect, having implemented auto-brightness on industrial control panels I designed.

If you need the front light on, on mono or colour eink, then a good LCD/OLED can be as good and some with similar battery charge use, if mobile, BT & WiFi is off (none of those needed to read a book). Mobile in standby (in case there is a call or SMS) is lower power use than active WiFi. Video, games, mobile data/voice are the big power users. Local audio playback might be as low or lower power on a phone than ereader if display sleeps and battery might be x5 bigger.

[John F]

[QUOTE=Quoth;4439035]So no matter how good matt OLED / LCD gets, it can only equal front lit eink, never be quite as good as ambient lit mono eink, ... /QUOTE]
That is surprising to me. I would think LCD/OLED could be superior. With eink, you are limited to the contrast of the panel, while with LCD/OLED the contrast and brightness can be independent?

[Quoth]

There is more to display quality than contrast. OLED certainly wins on contrast in a dim or dark area. LCD can be better in direct sunlight if a matt screen/filter and sufficient backlight power as OLED isn't real LEDs, but electroluminescent dots with phosphor and limited in power. QLED is actually LCD with pure blue LED backlight and quantum dots for red and green, so can be about x6 brighter, or 1/6th power.

With Carta you already have sufficient contrast and brightness for any ambient light good enough to read a paperback, and often Pearl is good enough if no layers.

Each layer reduces contrast: colour (printed ink for colour on eink or LCD or phosphor and CFA with OLED), a light pipe on top (eink), capacitive or resistive touch layers because each layer will reflect some light.

One aspect of increased contrast on Carta 1200 or maybe 1300 is to reduce layers by at least one by integrating capacitive touch and light-pipe rather than selling a bare eink panel to the OEM.

A matt top layer on LCD, OLED, QLED, VFD, LED and historically on plasma and CRT can increase contrast by being tinted as emitted light is attenuated once and reflected light off the interior panel is attentuated twice. That can't be done on eink unless you have it only front lit as it would attenuate ambient light.

So ultimately only mono eink has an advantage if ambient light is enough to read without front light. The front light lightpipe also reduces the sharpness and ambient brightness and ambient contrast a bit, hence a Pearl panel with IR touch and no front light can be nearly as good as original Carta with a front light and capacitive touch.

People say the Kindle Voyage has the best 300 dpi 6″ screen. The top surface is micro or nano-etched glass, so expensive compared to plastic matt surface and likely sharper. It also must have used a more expensive light pipe for the front lighting. The Oasis 1 is same panel (6″) so essentially the mythical Voyage 2 of goodereader. The paperwhite 3 is essentially a cost reduced Voyage (300 dpi 6″) and better than the paperwhite 4.
Yet by all accounts the earlier Voyage is better.
The Oasis 2 & 3 are 7″ and the Oasis 2 I had was no better than the Libra or Libra 2 (I had all 3 at the same time).

So it's complicated. But five things are clear:
1) If it's too dim to read using ambient light, you need the front light on and it's then just as emissive as LCD, as it's LEDs and a diffuser in front and LCD is LEDs and a diffuser behind (light pipe). The eink light pipe is more expensive as it mustn't blur the text. The LCD light pipe can be rubbishly cheap (the bad ones let you see bars/stripes of shadow).
2) The Kaleido 3 is printed coloured dots of red green and blue that don't cover the pixels, so it's pastel. They reflect, so contrast and brightness is reduced. Light has to go through them twice, unlike LCD stripes or dot colour print (LCDs are mono). So Kaleido eink isn not only poor colour but degrades the sharpness and contrast and brightness of the mono eink. You need the front light indoors, so it's emissive.
3) There is no advantage at to eink listening to audio books and it might be inferior (choice of supplier, no 3.5mm jack on Kobo or Kindle, charge run time).
4) The 4096 "colours" of Kaleido is not as big as it sounds, because that is all variations of saturation, brightness, contrast and hue. There are shades of pastel and murk, no nuances because the underlying mono eink is white, black and just about 14 greys. The LCD, OLED, QLED etc panels are mostly about 16 million and some do much more. You can actually simulate kaleido quality that's using a front light on LCD, OLED or QLED!
5) Kaleido is only 150 dpi in its poor colour. In mono you can't have the true 300 dpi of the mono panel. Driving at 300 dpi rather than 150 dpi in mono results in coloured artefacts. The coloured dots are printed translucent ink and there is screen door effect because they deliberately don't cover the pixels, so as to allow both a pseudo 300 dpi mono and to brighten the panel at expense of making colours at most pastel shades. Tertiary colours are thus poor.

Conclusion, only mono eink in ambient light with zero frontlight is totally like reading on paper and nothing else can quite match that unless the room lighting is completely diffused, or you are outside under a very overcast sky.

[Quoth]

Oh, and the Kindle Voyage was released on November 4, 2014, in the U.S. It has a 6-inch, 300 ppi E Ink Carta HD display, which was the highest resolution and contrast available in e-readers, as of 2014.
That will be 10 years ago this autumn. The Kaleido is simply a 2 x 2 pattern of coloured dots (about 4 years ago) because Triton (nearly 14 years ago!) was 3 x 1 like most LCD (some are 2 x 2) was too dark and also the mono pixels were square unlike 1/3rd width LCD mono pixels for colour stripes.

There could easily have been a Kaleido colour eink in 2014. It's only a dot pattern on a regular eink display.

Improvements in eink have been marginal since 2014. The 300 dpi is not yet exceeded, and larger panels have only slowly got higher resolution (Scribe is first 300 dpi over 10″). The larger panels are not yet 300 dpi.

ACeP is a different principle, in theory better than Kaleido for eink, but it seems doomed to very niche adverts due to being very slow. It's about EIGHT years old and getting no better.

Spectra can be seen in the supermarkets. White, red and black. Price tags seems to be biggest growth for eink. Quite low resolution, no power except from controller when updating. Larger panels look like mono Pearl. Aldi, Lidl and Musgraves (Supervalue, Centra etc).

Having had a reMarkable and still having a DXG (9.7″ Pearl) and Elispa (10.3″) I'm now of the conclusion that only mono eink is worth while and only up to 8″ (mostly novels), though maybe an 8.5″ to 9″ might be plausible. I tried the original (or near original) Sony in about 2006 and have had eink since 2013 and for ambient light reading a novel in mono it's excellent. I seriously consider large Sony DPT, Fujitsu etc and decided too limited for PDF. I got the Elipsa and within a month had 100% switched to a Sage. I gave away the reMarkable and no-one I know with an ereader wants the Elipsa, even free. Too big for novels and not good enough for PDFs.