which has better contrast ratio?

[Masa.F]

Hi.
I am considering to import an e-ink device.
Since I have no chance to see and compare them in person, I want to know which of entry models has better contrast ratio.
I would be appreciated if you would post some kind of ranking, like Nook<Kindle2<...
I know they are very subtle but I want to know before I decide to buy one.

[Magnesus]

Nook = Kindle2 = almost every other ereader with e-paper.

Every e-reader using e-paper right now uses the same Vizplex screen. The contrast is the same with exception of e-readers using non-wacom touch screens (like Sony PRS-600) which tend to have much worse contrast ratio.

Asus DR-900 will use Sipix e-paper which probably has... the same contrast ratio as Vizplex.

The only more contrasty device is Jetbook with reflective LCD (but the resolution is low and the screen is only 5'').

E Ink showed more contrasty (two times) Vizplex screens recently - but they will be available probably in 2011.

[Dellaster]

Actually there is a difference, though some may not notice in practice. The pic below shows the relative darkness of the screens in four e-ink devices. The blacks (text) on each is the same, so the lighter screen has the greater contrast.



The enTourage eDGe (big one) and iRex DR800SG (top-middle) are about the same. The Kindle 2 (top-left) is darker than those and much darker than the Cybook Gen3 (top-right). I went from the Cybook, my first e-ink device, to the Kindle and I was so disappointed.

For my eyes, the Kindle 2 has too low of a contrast. You need a brighter light to read it. The iRex and eDGe are fine. And that Cybook ... it must be because it only has four levels of gray or something. The contrast is just outstanding.

It's possible that YMMV. Different lots of e-ink may have different characteristics. I don't know.

[Magnesus]

Strange. I had two completely different e-readers (one with old 4 colour screen and one with new 8 colour one) and both had EXACTLY the same contrast.

The pic is misleading.
1) The readers have different colour borders. White border will make the screen look darker and black border - lighter (look for some optical illusions on googe graphics - the effect could be very strong). Also DR and contrast enhancer in photo camera could exaggerate the difference.
2) If you copy fragment of any screen to the one on the Entourage Edge screen in graphics editor you will notice that the only difference is in the part where there is obviously some light falling on the left side of the black device and right side of the middle one. Actually you even see part of the light patch on the top of the black LCD.

Differences you see may also be the reason of:
1) Partial instead of full refresh on some screens (huge difference in contrast),
2) Different fonts (very probable!),
3) Different antialiasing method for fonts (could make letters more gray).

[JSWolf]

Originally Posted by Masa.F

Hi.
I am considering to import an e-ink device.
Since I have no chance to see and compare them in person, I want to know which of entry models has better contrast ratio.
I would be appreciated if you would post some kind of ranking, like Nook<Kindle2<...
I know they are very subtle but I want to know before I decide to buy one.

if you want better contrast ratio, then wait. eink has show the next version eink that does have better contrast ratio then what we have now.

[Dellaster]

This makes it easier to see. I copied a square out of the Kindle 2's blank area (above the tree) and pasted it into the iRex and Cybook. There has been no adjustment to the photo since I took it except for size reduction (and cropping down to the three devices in this view).



Edit to add: Let me repeat that it may be possible that there is variation in the quality of output when these screens are made. I may have gotten an exceptionally good one with the Cybook and an exceptionally bad one with the Kindle 2. The only way to know is to compare with others and I only have these.

[Magnesus]

What I see on your photo is patch of light on the left of the black device and in the center of the middle one that is making those devices look lighter. The background on the left device could also be not white but one of the gray shades.
If you have the devices make a photo of every device in the same exact spot with M setting on the photo camera or make 3 photos shuffling the devices. And don't show the default off screen because it could be other gray level than white (was on one of the devices I had). Probably the best way to compare would be to show a white space below some text in an ebook.

Sorry for the distrust.

[Dellaster]

Originally Posted by Magnesus

The pic is misleading.

Agreed, it's not perfect. However, in all kinds of different lighting conditions, the relative difference holds up while reading. In my experience. I could have swapped the Kindle and Cybook in that photo and it would have been very nearly the same.

For what it's worth. I'm not on any crusade so I'll leave it here.

[Lindca2]

Another factor you might consider is what you are able to do with the text on different readers to make it more easily visible. One of the things I like about my Cybook is the ability to choose from twelve different font sizes (and any TT font you wish to load onto it) and the option to embolden the text. Even with the font size at its smallest, the embolden feature makes the text stand out.

[Dulin's Books]

its the software running the devices that makes the difference. I have seen on the same reader the "progress bar" appear darker from one firmware upgrade to the next. Also the anti-aliasing and embolden etc capabilities of the software make a big difference.

[Masa.F]

Thanks for the picture, Dellaster.
I searched for some comparison pictures and also found that the Kindle2 is a bit darker in almost every picture.
I am sure it is not just its white body makes it look darker.

[HarryT]

I have a Kindle, and numerous other devices, too, as you can see from my profile on the left. The background of the Kindle is exactly the same shade of grey as that of every other eInk device. The apparent colour of eInk screens does, however, vary considerably with the lighting conditions, and it's possible that, in photographs, the automatic white balance of the camera is picking up the white frame of the Kindle, and making the screen look darker by comparison.