My 19" LCD packed up the other night, and I thought I'd replace it with a
widescreen (20" or 21") LCD

I've heard good things about the BenQ 20" and about the LG monitors.

Anyone with personal experience with widescreen LCDs? It's going to be used
for graphics, movie watching (a little) and gaming.

I checked Tom's hardware, but all the LCD reviews I could see were last year

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"Gail Shaw" wrote:
> I've heard good things about the BenQ 20" and about the LG monitors.

I had a bad experience with an LG monitor, though it wasn't widescreen. I 
can no longer remember its name, but the problems were these two details:

1) The monitor used that technology (I've forgotten the name) where the 
brightness and colors are different depending on which angle you look at the 
monitor from. Most laptop monitors are like this too, but it was very 
uncomfortable for a stationary monitor, especially when working with 
graphics.

2) The monitor was not true 24-bit. Again, I have forgotten what it actually 
was, but it had fewer than 256 colors per channel, which were then 
interpolated. You couldn't see it most of the time, but when working with 
subtle gradient, like a blue sky, it was visible and annoying.

If you find an LG monitor that uses the angle-independent technology and is 
true 24 bit, then these observations don't apply of course.

Rune

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Rune escribió:
> 2) The monitor was not true 24-bit. Again, I have forgotten what it actually 
> was, but it had fewer than 256 colors per channel, which were then 
> interpolated. You couldn't see it most of the time, but when working with 
> subtle gradient, like a blue sky, it was visible and annoying.
> 
> If you find an LG monitor that uses the angle-independent technology and is 
> true 24 bit, then these observations don't apply of course.

Wow that sucks. I'm finding 256 colors per channel being not enough! 
(like on grayscale images :P)

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Nicolas Alvarez wrote:

> Wow that sucks. I'm finding 256 colors per channel being not enough! 
> (like on grayscale images :P)

That's... interesting. I'm fairly sure I read somewhere that for 
*greyscale* the human visual system can only distinguish about 16 
different levels. (Not sure whether that's *linear* though...)

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Orchid XP v7 escribió:
> Nicolas Alvarez wrote:
> 
>> Wow that sucks. I'm finding 256 colors per channel being not enough! 
>> (like on grayscale images :P)
> 
> That's... interesting. I'm fairly sure I read somewhere that for 
> *greyscale* the human visual system can only distinguish about 16 
> different levels. (Not sure whether that's *linear* though...)

Yeah, if I have 16 *consecutive* grayscale values (185, 186, 187, 188, 
189...) on an image, I can definitely distinguish them!

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Orchid XP v7 <voi### [at] devnull> wrote:
> That's... interesting. I'm fairly sure I read somewhere that for 
> *greyscale* the human visual system can only distinguish about 16 
> different levels.

  That's unusually easy to prove wrong. How many bars can you count in
this image? http://warp.povusers.org/images/grayscales.png

  The number you counted is the amount of grayscales you can distinguish
at least. (The true number is probably at least that times 10 or more.)

-- 
                                                          - Warp

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"Warp" wrote:
> Orchid XP v7 <voi### [at] devnull> wrote:
>> That's... interesting. I'm fairly sure I read somewhere that for
>> *greyscale* the human visual system can only distinguish about 16
>> different levels.
>
>  That's unusually easy to prove wrong. How many bars can you count in
> this image? http://warp.povusers.org/images/grayscales.png
>
>  The number you counted is the amount of grayscales you can distinguish
> at least. (The true number is probably at least that times 10 or more.)

While some cells in the eye may be able to distinguish that many colors, 
that doesn't mean that the visual system in the brain can. A lot of 
preprocessing is done in the eyes themselves before the visual data is sent 
to the brain.

For example, the eyes have an edge detecting layer I think, or something 
along those lines. This layer could find all the edges of the bars in your 
image and send information about these edges on to the brain, so that the 
brain can tell how many bars there are. The eyes also send the actual "raw" 
brightness info on to the brain, but this may be in a "low resolution" where 
no more than 16 different shades can be told apart. However, the brain can 
still count all the bars, becuase of the edges detected in the eyes.

I'm not saying it's like that; just that your image doesn't prove anything 
about the amount of gray scales the brain can tell apart. So it really comes 
down to what you mean by "human visual system" - the eyes or the brain.

Rune

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Warp escribió:
> Orchid XP v7 <voi### [at] devnull> wrote:
>> That's... interesting. I'm fairly sure I read somewhere that for 
>> *greyscale* the human visual system can only distinguish about 16 
>> different levels.
> 
>   That's unusually easy to prove wrong. How many bars can you count in
> this image? http://warp.povusers.org/images/grayscales.png
> 
>   The number you counted is the amount of grayscales you can distinguish
> at least. (The true number is probably at least that times 10 or more.)
> 
First two and last two look quite similar from some angles (damned LCD 
screen). Also, the black ones look all similar (damned gamma; the world 
would be a better place if screens had had built-in gamma correction 
since the beginning).

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Rune <aut### [at] runevisioncom> wrote:
> For example, the eyes have an edge detecting layer I think, or something 
> along those lines. This layer could find all the edges of the bars in your 
> image and send information about these edges on to the brain, so that the 
> brain can tell how many bars there are. The eyes also send the actual "raw" 
> brightness info on to the brain, but this may be in a "low resolution" where 
> no more than 16 different shades can be told apart. However, the brain can 
> still count all the bars, becuase of the edges detected in the eyes.

  I'm quite certain that if it was an animation where each frame is
completely filled by a shade of gray and was played eg. at 1 FPS, you
could clearly see the change.

-- 
                                                          - Warp

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Warp nous apporta ses lumieres en ce 2007/11/17 12:19:
> Orchid XP v7 <voi### [at] devnull> wrote:
>> That's... interesting. I'm fairly sure I read somewhere that for 
>> *greyscale* the human visual system can only distinguish about 16 
>> different levels.
> 
>   That's unusually easy to prove wrong. How many bars can you count in
> this image? http://warp.povusers.org/images/grayscales.png
> 
>   The number you counted is the amount of grayscales you can distinguish
> at least. (The true number is probably at least that times 10 or more.)
> 
I can count about 30 very distinct bands, monitor permiting.

-- 
Alain
-------------------------------------------------
A short cut is the longest distance between two points.

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