PocketBook Era Color

[cellaris]

I only intend to show how colour can be used in an e-reader, not how it looks. In this thread and others I have posted pictures and there are lots of videos where you can see what colour really looks like.

[cellaris]

Originally Posted by Michal Jancik

Is the device with the color screen in the attached photo Inkpad Color 3?
Could you add a comparison photo with PB Color 3 vs TCL NxtPaper ?
Gracias primo.

With no artistic pretensions and just to get an idea of the difference between a colour e-reader (Onyx Boox Tab Mini C) and a tablet (TCL NextPaper 11) I leave some images next to the window of my terrace (without illumination on the e-reader, and with the brightness at minimum and then in automatic mode on the tablet).

I repeat: No comparative or artistic validity. Only for the undemanding curious. There are videos on YouTube comparing the NextPaper 11 with e-readers (colour and monochrome).

[JSWolf]

Originally Posted by Michal Jancik

Interesting, because I can see the difference right away, with the Pocketbook ERA and the black ink seems to be a slightly faded color without the black depth as we can see, for example, with Tolino or Kobo.

I am quite surprised that Pocketbook allegedly wanted to optimize the screens of the ERA model, and yet another Inkpad 4 model suffers from the same problem.

PB ERA model after 2022:

Spoiler:

You can see it here ( Onyx Boox Leaf 2 ). It is the same E-INK screen, but the contrast is different due to the additional layer in the black model.

Look for time "3.10" :
https://youtu.be/sB12gbEI6J4?feature=shared&t=174

Would you mind another photo in a bright enough room with no front light on? The front lights are so different that it makes any comparison not possible. Thanks.

[JSWolf]

delete post

[Quoth]

Originally Posted by cellaris

There are videos on YouTube comparing the NextPaper 11 with e-readers (colour and monochrome).

Those are useless because videos don't have the image quality. I looked at several.

Also on Nxtpaper 11 it's important to do five things:
1) Switch off enhancements for reading as they make it worse. They are gimmicks like "feature modes on TVs"
2) Set colour mode to sRGB
3) On advanced almost centre the colour balance wheel which is neutral. The SW for that is broken as it doesn't change near peak white or peak white brightness colour balance, only less bright greyish whites.
4) Switch off auto-brightness. Like everything else with it since about 1956 (Some 1950s and 1960s TVs used to have it) it's mostly useless.
5) Set brightness so peak white is just slightly dimmer than fresh laser printer/copier paper in same ambient light. Basically about 13% to 27% unless you are outdoors.

Then comparative shots at normal same reading distance with a camera that does no processing. Ideally lock white balance and exposure or we can 't compare.

Also shots with no reflections and with a bright reflection on a shiny tablet/phone and the ereaders and Nxtpaper 11 at same location and distance.

This takes some practice to get right unless you are a serious photographer.

Specify what took the pictures and the ambient and reader/tablet light settings.

I can't see any photo there that looks remotely like what I see on my Nxtpaper 11.

Also you need some mono text (a novel), 1 up page portrait and 2up page portrait with reader/tablet held in landscape and also some PDF scans with dirty backgrounds.

[Quoth]

Originally Posted by cellaris

…
there are lots of videos where you can see what colour really looks like.

I have looked at loads of videos of colour eink and Nxtpaper 11, they vary from useless to downright dishonest (the ones by makers of Colour enk).

Also you are going to need a decent 4K HDR screen in a room with controlled lighting and 4K or better quality proper stills to be able to at all have an idea of the colour. Internet video is highly compressed and what you view on is important.

[cellaris]

Only direct vision can give an idea of the differences. Unfortunately only a few of us have a colour e-reader and the TCL NxtPaper 11 tablet. And in the end each person will decide according to his or her taste and preferences. I am one of the rare ones who prefers to read on a colour e-reader with all its shortcomings and limitations. If you don't mind reading on a tablet, the NextPaper 11 (or any other of higher quality in other respects) is a good and much cheaper option. You don't need videos or photos to make up your mind.

[Quoth]

Originally Posted by cellaris

Only direct vision can give an idea of the differences.

No, decent still photos taken at the same settings and conditions viewed on a decent monitor or laptop will give a very good idea of the differences.

Also there is more than personal preferences:
1) a screen with little glare/reflectance. This can be measured and reflections will give headaches.

2) Correctly adjusted brightness (active screens), or sufficient inherent brightness contrast for the ambient light (eink, mirasol and other bistable screens). This can be measured.

3) If colour or grey scale is needed, that it's sufficient for the application. Suitably prepared 1930s style comic can work on a colour screen with black, dark grey, light grey, white and two "brightnesses" each of six colours (R, G, B, C, Y, M) ideally with enough resolution for dithering. Some of us remember EGA. Some applications will be fine with about 30,000 to 60,000. Some need full colour, especially if the resolution is too low for dithering. Colour gamut can be measured or calculated.

4) Reading text has a minimum ppi for number of shades (fonts can be hinted and aliased also colour screens have sub pixel addressing.
a) On/off pixels (fixed dot size laser): 600 to 1200 dpi
b) eink (black, 14 greys & white): 220 to 300 ppi, thus a colour eink needs about 440 ppi if it's using a 2 x 2 cell and 660 x 220 ppi (x & y) for stripes.
c) 256 levels or more: About 200 ppi can look like 600 to 1200 laser or like 300 dpi eink due to better aliasing, even without subpixel addressing.
Resolution and colour cell layout can be measured.

Note colour LCD use mono panels either 3 x 1, or 2 x 2 the colour resolution. Some OLED and LCD use R G B Y or R G B Y and white for greater brightness. The colour rendition may be poorer.

5) Reponse time is how fast a pixel changes. A low as 0.3ms for LCD. OLED is limited by the phosphor. Eink is slow, AECP (Gallery is about 30x slower). Can be measured.

6) Refresh rate / Frame rate. About 120 fps is common now for OLED, LED, QLED, LCD and DLP. Higher is possible and three chip DLP can be 3 to 6 times faster. Eink about 2fps (full quality) to 10 fps (no shades). AECP (gallery 3) is 1.5 s per frame.

[Quoth]

If I was an avid reader of comics / graphic novels (and all of TinTin, Asterix and older Batman was economically available) and there was a colour eink at least 220 ppi for colour about 12″ to 14″ at under €450 I'd consider it. But current colour eink are too low resolution and too expensive and I rarely read comics/graphic novels apart from the cheap cartoon style UK ones when I was a kid. Not bought any in 20 years.

So it's partly personal preference. Currently the colour eink seem overpriced and over sold. It's just a mono eink with a colour filter. The eink generally are overpriced presumably due to E Ink Corp monopoly, or else the panels really are horrendously expensive compared to anything else except real LED (they are even more expensive).

[Michal Jancik]

Originally Posted by cellaris

With no artistic pretensions and just to get an idea of the difference

I repeat: No comparative or artistic validity. Only for the undemanding curious. There are videos on YouTube comparing the NextPaper 11 with e-readers (colour and monochrome).

Thank you very much for your time and the attached photos.
In a quick comparison, it is quite sufficient for me.

As for fidelity (closest to reality), we could debate who uses which monitor I have never seen "NextPaper 11" with my own eyes, for a quick comparison it is quite sufficient, once again thanks ..