Can you read complete books on an LCD screens?

[j.p.s]

Originally Posted by astrangerhere

Front Light vs. Back Light: Why Front Lights Are Eye-friendly

The direction the light is coming from, the type of light and the screen are all significant factors. The above article is from an e-ink vendor (BOOX), but does not make the points any less valid.

Maybe. But the caption

The backlight layer lies in the bottom and shoots into user's eyes directly. Source: Internet

for an image showing the light being reduced by 50% by a polarizing filter, then passing through a lossy pixelated liquid crystal polarizer, a color filter, and a final polarizing filter whose light reduction is image content dependent does reduce its credibility.

[DiapDealer]

Originally Posted by John F

No it didn't. Maybe you think it did for you. But it didn't for me.

Sure it did. You just didn't like the answer. There's a difference.

Originally Posted by John F

I thought you said you didn't have anything else to say.

As did you, I seem to recall.

Originally Posted by John F

I don't consider it an "Apple to oranges" comparison. They both have lights. There are comparable sizes now. I could see discomfort due to weight or form factor, but there seems to be an abundance of reports of eye fatigue from LCD. Is it refresh rates? Light level? ...

The question you asked IS an "Apples to Oranges" comparison (as at least 2 other posters have commented upon).

You asked no questions about eye fatigue, or its causes, and I offered no answers in that regard. But only because I don't really care who does or doesn't get it, or why they do or don't. Your question was:

Why don't those same people have the same problem when they switch to lit eink?

Which my reply answered (and others have already grasped).

I'm not one who prescribes to the notion that--lumen for lumen--direct light affects the eye any differently than indirect light does. I DO, however, prescribe to the notion the dimmer control on backlit devices has to be moved much, much farther to the negative in order to match the intensity of indirect, side-lit screens. Hence my Apples to Oranges answer. LCD needs more of an intensity range to cover all conditions than side-lit eink does.

The same people don't have the same problem when they switch to lit eink, because they simply can't generate the same levels of intensity with the indirect lighting technology used by side-lit eink devices as they can with backlit LCD devices. Mostly because it's not needed. LCD needs more intense backlighting for text to be legible in very bright ambient conditions. Eink requires less indirect side-lighting in bright ambient conditions in order to be legible. Apples to oranges.

[Paperbackstash]

I don't think the issue is only brightness, but also the screen material with the glare, even small amounts you may not notice offhand. Some people's eyes (like mine) are sensitive to it, and if there's a glare issue from angle or lighting, then your eyes may have to focus more to see the text clearer.

[kacir]

Originally Posted by ottischwenk

The difference is in transmitted light versus reflected light.
In the first case, you look directly into the light source, but not in the second case.
It is a completely different light quality.

A photon arriving at your retina that originated in a backlight LED is indistinguishable from the one that originated in a LED reading lamp and was reflected to your eye from an e-ink display.
The only difference is the level of ambient light and perhaps the frequency in which the light changes its intensity. Not the frequency of light wave itself - this is what color is, but the refresh frequency of display or perhaps frequency of the PWM regulator of display brightness.

Please note that in earlier post I stated that I vastly prefer reading fiction from an e-ink display (where I keep front-light level at a steady 1% - the lowest setting). I have read on LCD screens for years before e-ink devices became available, because I wanted to read in English and I had limited access to paper books in English here.
I work with computers almost whole day long and when I come home I might spend several hours in front of two monitors reading Mobileread, Reddit, watching Youtube, gathering info for my hobbies, helping kids with homework ...

[DiapDealer]

Originally Posted by Paperbackstash

I don't think the issue is only brightness, but also the screen material with the glare, even small amounts you may not notice offhand. Some people's eyes (like mine) are sensitive to it, and if there's a glare issue from angle or lighting, then your eyes may have to focus more to see the text clearer.

Very possible (though I've seen no technical articles on screen material/glare in that regard). As I said though, I'm not really interested in the who is/who isn't, who does/who doesn't aspect. I was merely commenting on the technical aspect of the one technical question that was posited by one person. People don't have to be told to turn the intensity down on side-lit eink devices because the lighting technologies are completely different. And because eink side-lighting is incapable of producing the intensities that LCD back-lighting can (sometimes, but not nearly always) need under certain ambient conditions. Different is different.

[ottischwenk]

Originally Posted by kacir

A photon arriving at your retina that originated in a backlight LED is indistinguishable from the one that originated in a LED reading lamp and was reflected to your eye from an e-ink display.

So far, so right - but you don't see single photons.

[MarjaE]

Originally Posted by JSWolf

Some do complain that LCD is too bright. So the possible solution is to turn down the brightness. Nobody is calling anyone stupid.

If I had given my Dad an iPad and he found it too bright, he would no have known how to turn the brightness down.

Okay. But there are a couple problems.

1. Most lcd devices are still too bright at 0% brightness. So users also need to know to install dimmer apps, or adjust the color profile, or otherwise reduce things below 0% brightness.

2. Many use pulse-width modulation, so reducing brightness increases flicker.

3. Many use full brightness for certain functions. My monitor uses it for parts of the brightness controls, laptops running KDE or Kubuntu used to use it for login, etc.

4. There's still the brightness vs. reflection trade off. So if we need to read despite the brightness, standard advice is to turn it down to 0% even if we've already brought it far below 0% and it's still too bright, and if we need to read despite the reflections, standard advice is to turn it up to 100%.

[JSWolf]

For those who find reading with LCD a problem, is it less of a problem to turn down the brightness in a brightly lit room or a room lit with sunlight?

[4691mls]

Originally Posted by JSWolf

For those who find reading with LCD a problem, is it less of a problem to turn down the brightness in a brightly lit room or a room lit with sunlight?

My attempts at using a phone as an ereader were mainly in my usual home setting, which is moderately lit - the room would have been neither super bright nor completely dark. So there was no problem seeing the screen and it didn't need the brightness set at a super high or low level.

I will use my phone to read if I have short periods of time available (like waiting in line at the post office) but if I'm going to have a marathon weekend reading session I want my e-ink.

[Sirtel]

Originally Posted by JSWolf

For those who find reading with LCD a problem, is it less of a problem to turn down the brightness in a brightly lit room or a room lit with sunlight?

All my screens are turned down exactly as much as is comfortable at the moment. Too dim in a bright environment and it's too much effort to see what's on the screen. Even with the screen brightness matching the ambient light I still can't read a novel on LCD without considerable discomfort, and it doesn't matter whether it's daylight or artificial light around me. Brightness of the screen is not the issue. It's something else, but I don't know what.

[hobnail]

Originally Posted by kacir

A photon arriving at your retina that originated in a backlight LED is indistinguishable from the one that originated in a LED reading lamp and was reflected to your eye from an e-ink display.

When reading on an lcd screen the light from the white background is projecting at your eyes. On an e-ink display the light from the white background has bounced off of that background, diffusing it and doing who knows what else to all of those photons. With an lcd screen it feels like I'm shining a light at my face (no matter how low it's turned down while remaining usable), which it does not with an e-ink display. And on an lcd display changing the background to tan or gray doesn't help, I still feel like I'm shining a light at my face.

[4691mls]

Originally Posted by hobnail

When reading on an lcd screen the light from the white background is projecting at your eyes. On an e-ink display the light from the white background has bounced off of that background, diffusing it and doing who knows what else to all of those photons. With an lcd screen it feels like I'm shining a light at my face (no matter how low it's turned down while remaining usable), which it does not with an e-ink display. And on an lcd display changing the background to tan or gray doesn't help, I still feel like I'm shining a light at my face.

Ditto.
Also, e-ink screen background looks solid unless I'm using it in total darkness with the reader light on. My phone screen never really looks solid to me.

[DiapDealer]

Ah... the ol' bouncy, ping-pong-ey, and ultimately unknowable effect of indirect light vs direct light. Perhaps all that bouncing around reduces the velocity of the photons so they strike the eyeballs with less force.

"and doing who knows what else to all those photons" Seriously?

[SteveEisenberg]

I voted yes. But if I have a choice -- as I usually do -- I read the book on eInk.

[JSWolf]

Originally Posted by hobnail

When reading on an lcd screen the light from the white background is projecting at your eyes. On an e-ink display the light from the white background has bounced off of that background, diffusing it and doing who knows what else to all of those photons. With an lcd screen it feels like I'm shining a light at my face (no matter how low it's turned down while remaining usable), which it does not with an e-ink display. And on an lcd display changing the background to tan or gray doesn't help, I still feel like I'm shining a light at my face.

So you prefer the bouncy-wouncy light vs. the straight light.

When I look at my H2O with the light on, I see the LEDs shining from under the bottom of the bezel. It's not bouncing off of the eInk screen. It's shining over the eInk screen from the bottom up. So from what I gather, the LCD screen is shining at you because the light is going up where the eInk light is not shining at you.

So the light for the eInk screen is not bouncy-wouncy.